Commit graph

11853 commits

Author SHA1 Message Date
Ondrej Mosnacek
7dabc4b45b cipso: fix total option length computation
[ Upstream commit 9f36169912 ]

As evident from the definition of ip_options_get(), the IP option
IPOPT_END is used to pad the IP option data array, not IPOPT_NOP. Yet
the loop that walks the IP options to determine the total IP options
length in cipso_v4_delopt() doesn't take IPOPT_END into account.

Fix it by recognizing the IPOPT_END value as the end of actual options.

Fixes: 014ab19a69 ("selinux: Set socket NetLabel based on connection endpoint")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:46:18 +02:00
Jason Xing
a2ab7dae67 tcp: count CLOSE-WAIT sockets for TCP_MIB_CURRESTAB
[ Upstream commit a46d0ea5c9 ]

According to RFC 1213, we should also take CLOSE-WAIT sockets into
consideration:

  "tcpCurrEstab OBJECT-TYPE
   ...
   The number of TCP connections for which the current state
   is either ESTABLISHED or CLOSE- WAIT."

After this, CurrEstab counter will display the total number of
ESTABLISHED and CLOSE-WAIT sockets.

The logic of counting
When we increment the counter?
a) if we change the state to ESTABLISHED.
b) if we change the state from SYN-RECEIVED to CLOSE-WAIT.

When we decrement the counter?
a) if the socket leaves ESTABLISHED and will never go into CLOSE-WAIT,
say, on the client side, changing from ESTABLISHED to FIN-WAIT-1.
b) if the socket leaves CLOSE-WAIT, say, on the server side, changing
from CLOSE-WAIT to LAST-ACK.

Please note: there are two chances that old state of socket can be changed
to CLOSE-WAIT in tcp_fin(). One is SYN-RECV, the other is ESTABLISHED.
So we have to take care of the former case.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:35:34 +02:00
Eric Dumazet
81dd3c82a4 net: fix __dst_negative_advice() race
commit 92f1655aa2 upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache,
then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly,
while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic
against RTF_CACHE, this means each of the three ->negative_advice()
existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in
__dst_negative_advice(), there is no need to duplicate
it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

Fixes: a87cb3e48e ("net: Facility to report route quality of connected sockets")
Reported-by: Clement Lecigne <clecigne@google.com>
Diagnosed-by: Clement Lecigne <clecigne@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Lee: Stable backport]
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:41:40 +02:00
Florian Westphal
caf3a8afb5 netfilter: tproxy: bail out if IP has been disabled on the device
[ Upstream commit 21a673bddc ]

syzbot reports:
general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
[..]
RIP: 0010:nf_tproxy_laddr4+0xb7/0x340 net/ipv4/netfilter/nf_tproxy_ipv4.c:62
Call Trace:
 nft_tproxy_eval_v4 net/netfilter/nft_tproxy.c:56 [inline]
 nft_tproxy_eval+0xa9a/0x1a00 net/netfilter/nft_tproxy.c:168

__in_dev_get_rcu() can return NULL, so check for this.

Reported-and-tested-by: syzbot+b94a6818504ea90d7661@syzkaller.appspotmail.com
Fixes: cc6eb43385 ("tproxy: use the interface primary IP address as a default value for --on-ip")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:57 +02:00
Paolo Abeni
c09ddc6058 net: relax socket state check at accept time.
[ Upstream commit 26afda78cd ]

Christoph reported the following splat:

WARNING: CPU: 1 PID: 772 at net/ipv4/af_inet.c:761 __inet_accept+0x1f4/0x4a0
Modules linked in:
CPU: 1 PID: 772 Comm: syz-executor510 Not tainted 6.9.0-rc7-g7da7119fe22b #56
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
RIP: 0010:__inet_accept+0x1f4/0x4a0 net/ipv4/af_inet.c:759
Code: 04 38 84 c0 0f 85 87 00 00 00 41 c7 04 24 03 00 00 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 ec b7 da fd <0f> 0b e9 7f fe ff ff e8 e0 b7 da fd 0f 0b e9 fe fe ff ff 89 d9 80
RSP: 0018:ffffc90000c2fc58 EFLAGS: 00010293
RAX: ffffffff836bdd14 RBX: 0000000000000000 RCX: ffff888104668000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff836bdb89 R09: fffff52000185f64
R10: dffffc0000000000 R11: fffff52000185f64 R12: dffffc0000000000
R13: 1ffff92000185f98 R14: ffff88810754d880 R15: ffff8881007b7800
FS:  000000001c772880(0000) GS:ffff88811b280000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb9fcf2e178 CR3: 00000001045d2002 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 inet_accept+0x138/0x1d0 net/ipv4/af_inet.c:786
 do_accept+0x435/0x620 net/socket.c:1929
 __sys_accept4_file net/socket.c:1969 [inline]
 __sys_accept4+0x9b/0x110 net/socket.c:1999
 __do_sys_accept net/socket.c:2016 [inline]
 __se_sys_accept net/socket.c:2013 [inline]
 __x64_sys_accept+0x7d/0x90 net/socket.c:2013
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0x100 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x4315f9
Code: fd ff 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 ab b4 fd ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdb26d9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002b
RAX: ffffffffffffffda RBX: 0000000000400300 RCX: 00000000004315f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00000000006e1018 R08: 0000000000400300 R09: 0000000000400300
R10: 0000000000400300 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000040cdf0 R14: 000000000040ce80 R15: 0000000000000055
 </TASK>

The reproducer invokes shutdown() before entering the listener status.
After commit 94062790ae ("tcp: defer shutdown(SEND_SHUTDOWN) for
TCP_SYN_RECV sockets"), the above causes the child to reach the accept
syscall in FIN_WAIT1 status.

Eric noted we can relax the existing assertion in __inet_accept()

Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/490
Suggested-by: Eric Dumazet <edumazet@google.com>
Fixes: 94062790ae ("tcp: defer shutdown(SEND_SHUTDOWN) for TCP_SYN_RECV sockets")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/23ab880a44d8cfd967e84de8b93dbf48848e3d8c.1716299669.git.pabeni@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:53 +02:00
Paolo Abeni
e1e80e7ff2 inet: factor out locked section of inet_accept() in a new helper
[ Upstream commit 711bdd5141 ]

No functional changes intended. The new helper will be used
by the MPTCP protocol in the next patch to avoid duplicating
a few LoC.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 26afda78cd ("net: relax socket state check at accept time.")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:53 +02:00
Kuniyuki Iwashima
e65d13ec00 tcp: Fix shift-out-of-bounds in dctcp_update_alpha().
[ Upstream commit 3ebc46ca86 ]

In dctcp_update_alpha(), we use a module parameter dctcp_shift_g
as follows:

  alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g);
  ...
  delivered_ce <<= (10 - dctcp_shift_g);

It seems syzkaller started fuzzing module parameters and triggered
shift-out-of-bounds [0] by setting 100 to dctcp_shift_g:

  memcpy((void*)0x20000080,
         "/sys/module/tcp_dctcp/parameters/dctcp_shift_g\000", 47);
  res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000080ul,
                /*flags=*/2ul, /*mode=*/0ul);
  memcpy((void*)0x20000000, "100\000", 4);
  syscall(__NR_write, /*fd=*/r[0], /*val=*/0x20000000ul, /*len=*/4ul);

Let's limit the max value of dctcp_shift_g by param_set_uint_minmax().

With this patch:

  # echo 10 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g
  # cat /sys/module/tcp_dctcp/parameters/dctcp_shift_g
  10
  # echo 11 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g
  -bash: echo: write error: Invalid argument

[0]:
UBSAN: shift-out-of-bounds in net/ipv4/tcp_dctcp.c:143:12
shift exponent 100 is too large for 32-bit type 'u32' (aka 'unsigned int')
CPU: 0 PID: 8083 Comm: syz-executor345 Not tainted 6.9.0-05151-g1b294a1f3561 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x201/0x300 lib/dump_stack.c:114
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x346/0x3a0 lib/ubsan.c:468
 dctcp_update_alpha+0x540/0x570 net/ipv4/tcp_dctcp.c:143
 tcp_in_ack_event net/ipv4/tcp_input.c:3802 [inline]
 tcp_ack+0x17b1/0x3bc0 net/ipv4/tcp_input.c:3948
 tcp_rcv_state_process+0x57a/0x2290 net/ipv4/tcp_input.c:6711
 tcp_v4_do_rcv+0x764/0xc40 net/ipv4/tcp_ipv4.c:1937
 sk_backlog_rcv include/net/sock.h:1106 [inline]
 __release_sock+0x20f/0x350 net/core/sock.c:2983
 release_sock+0x61/0x1f0 net/core/sock.c:3549
 mptcp_subflow_shutdown+0x3d0/0x620 net/mptcp/protocol.c:2907
 mptcp_check_send_data_fin+0x225/0x410 net/mptcp/protocol.c:2976
 __mptcp_close+0x238/0xad0 net/mptcp/protocol.c:3072
 mptcp_close+0x2a/0x1a0 net/mptcp/protocol.c:3127
 inet_release+0x190/0x1f0 net/ipv4/af_inet.c:437
 __sock_release net/socket.c:659 [inline]
 sock_close+0xc0/0x240 net/socket.c:1421
 __fput+0x41b/0x890 fs/file_table.c:422
 task_work_run+0x23b/0x300 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x9c8/0x2540 kernel/exit.c:878
 do_group_exit+0x201/0x2b0 kernel/exit.c:1027
 __do_sys_exit_group kernel/exit.c:1038 [inline]
 __se_sys_exit_group kernel/exit.c:1036 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xe4/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x67/0x6f
RIP: 0033:0x7f6c2b5005b6
Code: Unable to access opcode bytes at 0x7f6c2b50058c.
RSP: 002b:00007ffe883eb948 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f6c2b5862f0 RCX: 00007f6c2b5005b6
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
RBP: 0000000000000001 R08: 00000000000000e7 R09: ffffffffffffffc0
R10: 0000000000000006 R11: 0000000000000246 R12: 00007f6c2b5862f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
 </TASK>

Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: Yue Sun <samsun1006219@gmail.com>
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/netdev/CAEkJfYNJM=cw-8x7_Vmj1J6uYVCWMbbvD=EFmDPVBGpTsqOxEA@mail.gmail.com/
Fixes: e3118e8359 ("net: tcp: add DCTCP congestion control algorithm")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240517091626.32772-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:51 +02:00
Eric Dumazet
131490afa2 tcp: avoid premature drops in tcp_add_backlog()
[ Upstream commit ec00ed472b ]

While testing TCP performance with latest trees,
I saw suspect SOCKET_BACKLOG drops.

tcp_add_backlog() computes its limit with :

    limit = (u32)READ_ONCE(sk->sk_rcvbuf) +
            (u32)(READ_ONCE(sk->sk_sndbuf) >> 1);
    limit += 64 * 1024;

This does not take into account that sk->sk_backlog.len
is reset only at the very end of __release_sock().

Both sk->sk_backlog.len and sk->sk_rmem_alloc could reach
sk_rcvbuf in normal conditions.

We should double sk->sk_rcvbuf contribution in the formula
to absorb bubbles in the backlog, which happen more often
for very fast flows.

This change maintains decent protection against abuses.

Fixes: c377411f24 ("net: sk_add_backlog() take rmem_alloc into account")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240423125620.3309458-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:13 +02:00
Gabriel Krisman Bertazi
606dc69d6f udp: Avoid call to compute_score on multiple sites
[ Upstream commit 50aee97d15 ]

We've observed a 7-12% performance regression in iperf3 UDP ipv4 and
ipv6 tests with multiple sockets on Zen3 cpus, which we traced back to
commit f0ea27e7bf ("udp: re-score reuseport groups when connected
sockets are present").  The failing tests were those that would spawn
UDP sockets per-cpu on systems that have a high number of cpus.

Unsurprisingly, it is not caused by the extra re-scoring of the reused
socket, but due to the compiler no longer inlining compute_score, once
it has the extra call site in udp4_lib_lookup2.  This is augmented by
the "Safe RET" mitigation for SRSO, needed in our Zen3 cpus.

We could just explicitly inline it, but compute_score() is quite a large
function, around 300b.  Inlining in two sites would almost double
udp4_lib_lookup2, which is a silly thing to do just to workaround a
mitigation.  Instead, this patch shuffles the code a bit to avoid the
multiple calls to compute_score.  Since it is a static function used in
one spot, the compiler can safely fold it in, as it did before, without
increasing the text size.

With this patch applied I ran my original iperf3 testcases.  The failing
cases all looked like this (ipv4):
	iperf3 -c 127.0.0.1 --udp -4 -f K -b $R -l 8920 -t 30 -i 5 -P 64 -O 2

where $R is either 1G/10G/0 (max, unlimited).  I ran 3 times each.
baseline is v6.9-rc3. harmean == harmonic mean; CV == coefficient of
variation.

ipv4:
                 1G                10G                  MAX
	    HARMEAN  (CV)      HARMEAN  (CV)    HARMEAN     (CV)
baseline 1743852.66(0.0208) 1725933.02(0.0167) 1705203.78(0.0386)
patched  1968727.61(0.0035) 1962283.22(0.0195) 1923853.50(0.0256)

ipv6:
                 1G                10G                  MAX
	    HARMEAN  (CV)      HARMEAN  (CV)    HARMEAN     (CV)
baseline 1729020.03(0.0028) 1691704.49(0.0243) 1692251.34(0.0083)
patched  1900422.19(0.0067) 1900968.01(0.0067) 1568532.72(0.1519)

This restores the performance we had before the change above with this
benchmark.  We obviously don't expect any real impact when mitigations
are disabled, but just to be sure it also doesn't regresses:

mitigations=off ipv4:
                 1G                10G                  MAX
	    HARMEAN  (CV)      HARMEAN  (CV)    HARMEAN     (CV)
baseline 3230279.97(0.0066) 3229320.91(0.0060) 2605693.19(0.0697)
patched  3242802.36(0.0073) 3239310.71(0.0035) 2502427.19(0.0882)

Cc: Lorenz Bauer <lmb@isovalent.com>
Fixes: f0ea27e7bf ("udp: re-score reuseport groups when connected sockets are present")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:12 +02:00
Lorenz Bauer
789afa3e00 net: remove duplicate reuseport_lookup functions
[ Upstream commit 0f495f7617 ]

There are currently four copies of reuseport_lookup: one each for
(TCP, UDP)x(IPv4, IPv6). This forces us to duplicate all callers of
those functions as well. This is already the case for sk_lookup
helpers (inet,inet6,udp4,udp6)_lookup_run_bpf.

There are two differences between the reuseport_lookup helpers:

1. They call different hash functions depending on protocol
2. UDP reuseport_lookup checks that sk_state != TCP_ESTABLISHED

Move the check for sk_state into the caller and use the INDIRECT_CALL
infrastructure to cut down the helpers to one per IP version.

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-4-7021b683cdae@isovalent.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Stable-dep-of: 50aee97d15 ("udp: Avoid call to compute_score on multiple sites")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:12 +02:00
Lorenz Bauer
1191892924 net: export inet_lookup_reuseport and inet6_lookup_reuseport
[ Upstream commit ce796e60b3 ]

Rename the existing reuseport helpers for IPv4 and IPv6 so that they
can be invoked in the follow up commit. Export them so that building
DCCP and IPv6 as a module works.

No change in functionality.

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-3-7021b683cdae@isovalent.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Stable-dep-of: 50aee97d15 ("udp: Avoid call to compute_score on multiple sites")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:11 +02:00
Kuniyuki Iwashima
13ed7cdf07 tcp: Use refcount_inc_not_zero() in tcp_twsk_unique().
[ Upstream commit f2db7230f7 ]

Anderson Nascimento reported a use-after-free splat in tcp_twsk_unique()
with nice analysis.

Since commit ec94c2696f ("tcp/dccp: avoid one atomic operation for
timewait hashdance"), inet_twsk_hashdance() sets TIME-WAIT socket's
sk_refcnt after putting it into ehash and releasing the bucket lock.

Thus, there is a small race window where other threads could try to
reuse the port during connect() and call sock_hold() in tcp_twsk_unique()
for the TIME-WAIT socket with zero refcnt.

If that happens, the refcnt taken by tcp_twsk_unique() is overwritten
and sock_put() will cause underflow, triggering a real use-after-free
somewhere else.

To avoid the use-after-free, we need to use refcount_inc_not_zero() in
tcp_twsk_unique() and give up on reusing the port if it returns false.

[0]:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 1039313 at lib/refcount.c:25 refcount_warn_saturate+0xe5/0x110
CPU: 0 PID: 1039313 Comm: trigger Not tainted 6.8.6-200.fc39.x86_64 #1
Hardware name: VMware, Inc. VMware20,1/440BX Desktop Reference Platform, BIOS VMW201.00V.21805430.B64.2305221830 05/22/2023
RIP: 0010:refcount_warn_saturate+0xe5/0x110
Code: 42 8e ff 0f 0b c3 cc cc cc cc 80 3d aa 13 ea 01 00 0f 85 5e ff ff ff 48 c7 c7 f8 8e b7 82 c6 05 96 13 ea 01 01 e8 7b 42 8e ff <0f> 0b c3 cc cc cc cc 48 c7 c7 50 8f b7 82 c6 05 7a 13 ea 01 01 e8
RSP: 0018:ffffc90006b43b60 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff888009bb3ef0 RCX: 0000000000000027
RDX: ffff88807be218c8 RSI: 0000000000000001 RDI: ffff88807be218c0
RBP: 0000000000069d70 R08: 0000000000000000 R09: ffffc90006b439f0
R10: ffffc90006b439e8 R11: 0000000000000003 R12: ffff8880029ede84
R13: 0000000000004e20 R14: ffffffff84356dc0 R15: ffff888009bb3ef0
FS:  00007f62c10926c0(0000) GS:ffff88807be00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020ccb000 CR3: 000000004628c005 CR4: 0000000000f70ef0
PKRU: 55555554
Call Trace:
 <TASK>
 ? refcount_warn_saturate+0xe5/0x110
 ? __warn+0x81/0x130
 ? refcount_warn_saturate+0xe5/0x110
 ? report_bug+0x171/0x1a0
 ? refcount_warn_saturate+0xe5/0x110
 ? handle_bug+0x3c/0x80
 ? exc_invalid_op+0x17/0x70
 ? asm_exc_invalid_op+0x1a/0x20
 ? refcount_warn_saturate+0xe5/0x110
 tcp_twsk_unique+0x186/0x190
 __inet_check_established+0x176/0x2d0
 __inet_hash_connect+0x74/0x7d0
 ? __pfx___inet_check_established+0x10/0x10
 tcp_v4_connect+0x278/0x530
 __inet_stream_connect+0x10f/0x3d0
 inet_stream_connect+0x3a/0x60
 __sys_connect+0xa8/0xd0
 __x64_sys_connect+0x18/0x20
 do_syscall_64+0x83/0x170
 entry_SYSCALL_64_after_hwframe+0x78/0x80
RIP: 0033:0x7f62c11a885d
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a3 45 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007f62c1091e58 EFLAGS: 00000296 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000020ccb004 RCX: 00007f62c11a885d
RDX: 0000000000000010 RSI: 0000000020ccb000 RDI: 0000000000000003
RBP: 00007f62c1091e90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 00007f62c10926c0
R13: ffffffffffffff88 R14: 0000000000000000 R15: 00007ffe237885b0
 </TASK>

Fixes: ec94c2696f ("tcp/dccp: avoid one atomic operation for timewait hashdance")
Reported-by: Anderson Nascimento <anderson@allelesecurity.com>
Closes: https://lore.kernel.org/netdev/37a477a6-d39e-486b-9577-3463f655a6b7@allelesecurity.com/
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240501213145.62261-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:11 +02:00
Eric Dumazet
3fe4ef0568 tcp: defer shutdown(SEND_SHUTDOWN) for TCP_SYN_RECV sockets
[ Upstream commit 94062790ae ]

TCP_SYN_RECV state is really special, it is only used by
cross-syn connections, mostly used by fuzzers.

In the following crash [1], syzbot managed to trigger a divide
by zero in tcp_rcv_space_adjust()

A socket makes the following state transitions,
without ever calling tcp_init_transfer(),
meaning tcp_init_buffer_space() is also not called.

         TCP_CLOSE
connect()
         TCP_SYN_SENT
         TCP_SYN_RECV
shutdown() -> tcp_shutdown(sk, SEND_SHUTDOWN)
         TCP_FIN_WAIT1

To fix this issue, change tcp_shutdown() to not
perform a TCP_SYN_RECV -> TCP_FIN_WAIT1 transition,
which makes no sense anyway.

When tcp_rcv_state_process() later changes socket state
from TCP_SYN_RECV to TCP_ESTABLISH, then look at
sk->sk_shutdown to finally enter TCP_FIN_WAIT1 state,
and send a FIN packet from a sane socket state.

This means tcp_send_fin() can now be called from BH
context, and must use GFP_ATOMIC allocations.

[1]
divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 1 PID: 5084 Comm: syz-executor358 Not tainted 6.9.0-rc6-syzkaller-00022-g98369dccd2f8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
 RIP: 0010:tcp_rcv_space_adjust+0x2df/0x890 net/ipv4/tcp_input.c:767
Code: e3 04 4c 01 eb 48 8b 44 24 38 0f b6 04 10 84 c0 49 89 d5 0f 85 a5 03 00 00 41 8b 8e c8 09 00 00 89 e8 29 c8 48 0f af c3 31 d2 <48> f7 f1 48 8d 1c 43 49 8d 96 76 08 00 00 48 89 d0 48 c1 e8 03 48
RSP: 0018:ffffc900031ef3f0 EFLAGS: 00010246
RAX: 0c677a10441f8f42 RBX: 000000004fb95e7e RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000027d4b11f R08: ffffffff89e535a4 R09: 1ffffffff25e6ab7
R10: dffffc0000000000 R11: ffffffff8135e920 R12: ffff88802a9f8d30
R13: dffffc0000000000 R14: ffff88802a9f8d00 R15: 1ffff1100553f2da
FS:  00005555775c0380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1155bf2304 CR3: 000000002b9f2000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
  tcp_recvmsg_locked+0x106d/0x25a0 net/ipv4/tcp.c:2513
  tcp_recvmsg+0x25d/0x920 net/ipv4/tcp.c:2578
  inet6_recvmsg+0x16a/0x730 net/ipv6/af_inet6.c:680
  sock_recvmsg_nosec net/socket.c:1046 [inline]
  sock_recvmsg+0x109/0x280 net/socket.c:1068
  ____sys_recvmsg+0x1db/0x470 net/socket.c:2803
  ___sys_recvmsg net/socket.c:2845 [inline]
  do_recvmmsg+0x474/0xae0 net/socket.c:2939
  __sys_recvmmsg net/socket.c:3018 [inline]
  __do_sys_recvmmsg net/socket.c:3041 [inline]
  __se_sys_recvmmsg net/socket.c:3034 [inline]
  __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faeb6363db9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcc1997168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007faeb6363db9
RDX: 0000000000000001 RSI: 0000000020000bc0 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000001c
R10: 0000000000000122 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240501125448.896529-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:11 +02:00
Paul Davey
179db49d7e xfrm: Preserve vlan tags for transport mode software GRO
[ Upstream commit 58fbfecab9 ]

The software GRO path for esp transport mode uses skb_mac_header_rebuild
prior to re-injecting the packet via the xfrm_napi_dev.  This only
copies skb->mac_len bytes of header which may not be sufficient if the
packet contains 802.1Q tags or other VLAN tags.  Worse copying only the
initial header will leave a packet marked as being VLAN tagged but
without the corresponding tag leading to mangling when it is later
untagged.

The VLAN tags are important when receiving the decrypted esp transport
mode packet after GRO processing to ensure it is received on the correct
interface.

Therefore record the full mac header length in xfrm*_transport_input for
later use in corresponding xfrm*_transport_finish to copy the entire mac
header when rebuilding the mac header for GRO.  The skb->data pointer is
left pointing skb->mac_header bytes after the start of the mac header as
is expected by the network stack and network and transport header
offsets reset to this location.

Fixes: 7785bba299 ("esp: Add a software GRO codepath")
Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:10 +02:00
Richard Gobert
463c15af49 net: gro: add flush check in udp_gro_receive_segment
[ Upstream commit 5babae777c ]

GRO-GSO path is supposed to be transparent and as such L3 flush checks are
relevant to all UDP flows merging in GRO. This patch uses the same logic
and code from tcp_gro_receive, terminating merge if flush is non zero.

Fixes: e20cf8d3f1 ("udp: implement GRO for plain UDP sockets.")
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:02 +02:00
Yick Xie
4ebf1ff60e udp: preserve the connected status if only UDP cmsg
commit 680d11f6e5 upstream.

If "udp_cmsg_send()" returned 0 (i.e. only UDP cmsg),
"connected" should not be set to 0. Otherwise it stops
the connected socket from using the cached route.

Fixes: 2e8de85763 ("udp: add gso segment cmsg")
Signed-off-by: Yick Xie <yick.xie@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240418170610.867084-1-yick.xie@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-02 16:29:30 +02:00
Eric Dumazet
7a25bfd127 ipv4: check for NULL idev in ip_route_use_hint()
[ Upstream commit 58a4c9b1e5 ]

syzbot was able to trigger a NULL deref in fib_validate_source()
in an old tree [1].

It appears the bug exists in latest trees.

All calls to __in_dev_get_rcu() must be checked for a NULL result.

[1]
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 2 PID: 3257 Comm: syz-executor.3 Not tainted 5.10.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
 RIP: 0010:fib_validate_source+0xbf/0x15a0 net/ipv4/fib_frontend.c:425
Code: 18 f2 f2 f2 f2 42 c7 44 20 23 f3 f3 f3 f3 48 89 44 24 78 42 c6 44 20 27 f3 e8 5d 88 48 fc 4c 89 e8 48 c1 e8 03 48 89 44 24 18 <42> 80 3c 20 00 74 08 4c 89 ef e8 d2 15 98 fc 48 89 5c 24 10 41 bf
RSP: 0018:ffffc900015fee40 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88800f7a4000 RCX: ffff88800f4f90c0
RDX: 0000000000000000 RSI: 0000000004001eac RDI: ffff8880160c64c0
RBP: ffffc900015ff060 R08: 0000000000000000 R09: ffff88800f7a4000
R10: 0000000000000002 R11: ffff88800f4f90c0 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88800f7a4000
FS:  00007f938acfe6c0(0000) GS:ffff888058c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f938acddd58 CR3: 000000001248e000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  ip_route_use_hint+0x410/0x9b0 net/ipv4/route.c:2231
  ip_rcv_finish_core+0x2c4/0x1a30 net/ipv4/ip_input.c:327
  ip_list_rcv_finish net/ipv4/ip_input.c:612 [inline]
  ip_sublist_rcv+0x3ed/0xe50 net/ipv4/ip_input.c:638
  ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:673
  __netif_receive_skb_list_ptype net/core/dev.c:5572 [inline]
  __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5620
  __netif_receive_skb_list net/core/dev.c:5672 [inline]
  netif_receive_skb_list_internal+0x9f9/0xdc0 net/core/dev.c:5764
  netif_receive_skb_list+0x55/0x3e0 net/core/dev.c:5816
  xdp_recv_frames net/bpf/test_run.c:257 [inline]
  xdp_test_run_batch net/bpf/test_run.c:335 [inline]
  bpf_test_run_xdp_live+0x1818/0x1d00 net/bpf/test_run.c:363
  bpf_prog_test_run_xdp+0x81f/0x1170 net/bpf/test_run.c:1376
  bpf_prog_test_run+0x349/0x3c0 kernel/bpf/syscall.c:3736
  __sys_bpf+0x45c/0x710 kernel/bpf/syscall.c:5115
  __do_sys_bpf kernel/bpf/syscall.c:5201 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:5199 [inline]
  __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5199

Fixes: 02b2494161 ("ipv4: use dst hint for ipv4 list receive")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240421184326.1704930-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-02 16:29:24 +02:00
Eric Dumazet
599c9ad5e1 icmp: prevent possible NULL dereferences from icmp_build_probe()
[ Upstream commit c58e88d490 ]

First problem is a double call to __in_dev_get_rcu(), because
the second one could return NULL.

if (__in_dev_get_rcu(dev) && __in_dev_get_rcu(dev)->ifa_list)

Second problem is a read from dev->ip6_ptr with no NULL check:

if (!list_empty(&rcu_dereference(dev->ip6_ptr)->addr_list))

Use the correct RCU API to fix these.

v2: add missing include <net/addrconf.h>

Fixes: d329ea5bd8 ("icmp: add response to RFC 8335 PROBE messages")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Andreas Roeseler <andreas.a.roeseler@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-02 16:29:23 +02:00
Eric Dumazet
c760089aa9 netfilter: complete validation of user input
[ Upstream commit 65acf6e050 ]

In my recent commit, I missed that do_replace() handlers
use copy_from_sockptr() (which I fixed), followed
by unsafe copy_from_sockptr_offset() calls.

In all functions, we can perform the @optlen validation
before even calling xt_alloc_table_info() with the following
check:

if ((u64)optlen < (u64)tmp.size + sizeof(tmp))
        return -EINVAL;

Fixes: 0c83842df4 ("netfilter: validate user input for expected length")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/r/20240409120741.3538135-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-17 11:18:25 +02:00
Arnd Bergmann
03d564999f ipv4/route: avoid unused-but-set-variable warning
[ Upstream commit cf1b7201df ]

The log_martians variable is only used in an #ifdef, causing a 'make W=1'
warning with gcc:

net/ipv4/route.c: In function 'ip_rt_send_redirect':
net/ipv4/route.c:880:13: error: variable 'log_martians' set but not used [-Werror=unused-but-set-variable]

Change the #ifdef to an equivalent IS_ENABLED() to let the compiler
see where the variable is used.

Fixes: 30038fc61a ("net: ip_rt_send_redirect() optimization")
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240408074219.3030256-2-arnd@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-17 11:18:24 +02:00
Kuniyuki Iwashima
4eed9d0a48 tcp: Fix bind() regression for v6-only wildcard and v4(-mapped-v6) non-wildcard addresses.
[ Upstream commit d91ef1e1b5 ]

Jianguo Wu reported another bind() regression introduced by bhash2.

Calling bind() for the following 3 addresses on the same port, the
3rd one should fail but now succeeds.

  1. 0.0.0.0 or ::ffff:0.0.0.0
  2. [::] w/ IPV6_V6ONLY
  3. IPv4 non-wildcard address or v4-mapped-v6 non-wildcard address

The first two bind() create tb2 like this:

  bhash2 -> tb2(:: w/ IPV6_V6ONLY) -> tb2(0.0.0.0)

The 3rd bind() will match with the IPv6 only wildcard address bucket
in inet_bind2_bucket_match_addr_any(), however, no conflicting socket
exists in the bucket.  So, inet_bhash2_conflict() will returns false,
and thus, inet_bhash2_addr_any_conflict() returns false consequently.

As a result, the 3rd bind() bypasses conflict check, which should be
done against the IPv4 wildcard address bucket.

So, in inet_bhash2_addr_any_conflict(), we must iterate over all buckets.

Note that we cannot add ipv6_only flag for inet_bind2_bucket as it
would confuse the following patetrn.

  1. [::] w/ SO_REUSE{ADDR,PORT} and IPV6_V6ONLY
  2. [::] w/ SO_REUSE{ADDR,PORT}
  3. IPv4 non-wildcard address or v4-mapped-v6 non-wildcard address

The first bind() would create a bucket with ipv6_only flag true,
the second bind() would add the [::] socket into the same bucket,
and the third bind() could succeed based on the wrong assumption
that ipv6_only bucket would not conflict with v4(-mapped-v6) address.

Fixes: 28044fc1d4 ("net: Add a bhash2 table hashed by port and address")
Diagnosed-by: Jianguo Wu <wujianguo106@163.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-10 16:28:29 +02:00
Antoine Tenart
940ff35ae8 udp: prevent local UDP tunnel packets from being GROed
commit 64235eabc4 upstream.

GRO has a fundamental issue with UDP tunnel packets as it can't detect
those in a foolproof way and GRO could happen before they reach the
tunnel endpoint. Previous commits have fixed issues when UDP tunnel
packets come from a remote host, but if those packets are issued locally
they could run into checksum issues.

If the inner packet has a partial checksum the information will be lost
in the GRO logic, either in udp4/6_gro_complete or in
udp_gro_complete_segment and packets will have an invalid checksum when
leaving the host.

Prevent local UDP tunnel packets from ever being GROed at the outer UDP
level.

Due to skb->encapsulation being wrongly used in some drivers this is
actually only preventing UDP tunnel packets with a partial checksum to
be GROed (see iptunnel_handle_offloads) but those were also the packets
triggering issues so in practice this should be sufficient.

Fixes: 9fd1ff5d2a ("udp: Support UDP fraglist GRO/GSO.")
Fixes: 36707061d6 ("udp: allow forwarding of plain (non-fraglisted) UDP GRO packets")
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:27 +02:00
Antoine Tenart
8c58d38405 udp: do not transition UDP GRO fraglist partial checksums to unnecessary
commit f0b8c30345 upstream.

UDP GRO validates checksums and in udp4/6_gro_complete fraglist packets
are converted to CHECKSUM_UNNECESSARY to avoid later checks. However
this is an issue for CHECKSUM_PARTIAL packets as they can be looped in
an egress path and then their partial checksums are not fixed.

Different issues can be observed, from invalid checksum on packets to
traces like:

  gen01: hw csum failure
  skb len=3008 headroom=160 headlen=1376 tailroom=0
  mac=(106,14) net=(120,40) trans=160
  shinfo(txflags=0 nr_frags=0 gso(size=0 type=0 segs=0))
  csum(0xffff232e ip_summed=2 complete_sw=0 valid=0 level=0)
  hash(0x77e3d716 sw=1 l4=1) proto=0x86dd pkttype=0 iif=12
  ...

Fix this by only converting CHECKSUM_NONE packets to
CHECKSUM_UNNECESSARY by reusing __skb_incr_checksum_unnecessary. All
other checksum types are kept as-is, including CHECKSUM_COMPLETE as
fraglist packets being segmented back would have their skb->csum valid.

Fixes: 9fd1ff5d2a ("udp: Support UDP fraglist GRO/GSO.")
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:27 +02:00
Antoine Tenart
d12245080c udp: do not accept non-tunnel GSO skbs landing in a tunnel
commit 3d010c8031 upstream.

When rx-udp-gro-forwarding is enabled UDP packets might be GROed when
being forwarded. If such packets might land in a tunnel this can cause
various issues and udp_gro_receive makes sure this isn't the case by
looking for a matching socket. This is performed in
udp4/6_gro_lookup_skb but only in the current netns. This is an issue
with tunneled packets when the endpoint is in another netns. In such
cases the packets will be GROed at the UDP level, which leads to various
issues later on. The same thing can happen with rx-gro-list.

We saw this with geneve packets being GROed at the UDP level. In such
case gso_size is set; later the packet goes through the geneve rx path,
the geneve header is pulled, the offset are adjusted and frag_list skbs
are not adjusted with regard to geneve. When those skbs hit
skb_fragment, it will misbehave. Different outcomes are possible
depending on what the GROed skbs look like; from corrupted packets to
kernel crashes.

One example is a BUG_ON[1] triggered in skb_segment while processing the
frag_list. Because gso_size is wrong (geneve header was pulled)
skb_segment thinks there is "geneve header size" of data in frag_list,
although it's in fact the next packet. The BUG_ON itself has nothing to
do with the issue. This is only one of the potential issues.

Looking up for a matching socket in udp_gro_receive is fragile: the
lookup could be extended to all netns (not speaking about performances)
but nothing prevents those packets from being modified in between and we
could still not find a matching socket. It's OK to keep the current
logic there as it should cover most cases but we also need to make sure
we handle tunnel packets being GROed too early.

This is done by extending the checks in udp_unexpected_gso: GSO packets
lacking the SKB_GSO_UDP_TUNNEL/_CSUM bits and landing in a tunnel must
be segmented.

[1] kernel BUG at net/core/skbuff.c:4408!
    RIP: 0010:skb_segment+0xd2a/0xf70
    __udp_gso_segment+0xaa/0x560

Fixes: 9fd1ff5d2a ("udp: Support UDP fraglist GRO/GSO.")
Fixes: 36707061d6 ("udp: allow forwarding of plain (non-fraglisted) UDP GRO packets")
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:27 +02:00
Eric Dumazet
1db7fcb2b2 erspan: make sure erspan_base_hdr is present in skb->head
commit 17af420545 upstream.

syzbot reported a problem in ip6erspan_rcv() [1]

Issue is that ip6erspan_rcv() (and erspan_rcv()) no longer make
sure erspan_base_hdr is present in skb linear part (skb->head)
before getting @ver field from it.

Add the missing pskb_may_pull() calls.

v2: Reload iph pointer in erspan_rcv() after pskb_may_pull()
    because skb->head might have changed.

[1]

 BUG: KMSAN: uninit-value in pskb_may_pull_reason include/linux/skbuff.h:2742 [inline]
 BUG: KMSAN: uninit-value in pskb_may_pull include/linux/skbuff.h:2756 [inline]
 BUG: KMSAN: uninit-value in ip6erspan_rcv net/ipv6/ip6_gre.c:541 [inline]
 BUG: KMSAN: uninit-value in gre_rcv+0x11f8/0x1930 net/ipv6/ip6_gre.c:610
  pskb_may_pull_reason include/linux/skbuff.h:2742 [inline]
  pskb_may_pull include/linux/skbuff.h:2756 [inline]
  ip6erspan_rcv net/ipv6/ip6_gre.c:541 [inline]
  gre_rcv+0x11f8/0x1930 net/ipv6/ip6_gre.c:610
  ip6_protocol_deliver_rcu+0x1d4c/0x2ca0 net/ipv6/ip6_input.c:438
  ip6_input_finish net/ipv6/ip6_input.c:483 [inline]
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ip6_input+0x15d/0x430 net/ipv6/ip6_input.c:492
  ip6_mc_input+0xa7e/0xc80 net/ipv6/ip6_input.c:586
  dst_input include/net/dst.h:460 [inline]
  ip6_rcv_finish+0x955/0x970 net/ipv6/ip6_input.c:79
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ipv6_rcv+0xde/0x390 net/ipv6/ip6_input.c:310
  __netif_receive_skb_one_core net/core/dev.c:5538 [inline]
  __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5652
  netif_receive_skb_internal net/core/dev.c:5738 [inline]
  netif_receive_skb+0x58/0x660 net/core/dev.c:5798
  tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1549
  tun_get_user+0x5566/0x69e0 drivers/net/tun.c:2002
  tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
  call_write_iter include/linux/fs.h:2108 [inline]
  new_sync_write fs/read_write.c:497 [inline]
  vfs_write+0xb63/0x1520 fs/read_write.c:590
  ksys_write+0x20f/0x4c0 fs/read_write.c:643
  __do_sys_write fs/read_write.c:655 [inline]
  __se_sys_write fs/read_write.c:652 [inline]
  __x64_sys_write+0x93/0xe0 fs/read_write.c:652
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
  slab_post_alloc_hook mm/slub.c:3804 [inline]
  slab_alloc_node mm/slub.c:3845 [inline]
  kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
  kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
  __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
  alloc_skb include/linux/skbuff.h:1318 [inline]
  alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504
  sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795
  tun_alloc_skb drivers/net/tun.c:1525 [inline]
  tun_get_user+0x209a/0x69e0 drivers/net/tun.c:1846
  tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
  call_write_iter include/linux/fs.h:2108 [inline]
  new_sync_write fs/read_write.c:497 [inline]
  vfs_write+0xb63/0x1520 fs/read_write.c:590
  ksys_write+0x20f/0x4c0 fs/read_write.c:643
  __do_sys_write fs/read_write.c:655 [inline]
  __se_sys_write fs/read_write.c:652 [inline]
  __x64_sys_write+0x93/0xe0 fs/read_write.c:652
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

CPU: 1 PID: 5045 Comm: syz-executor114 Not tainted 6.9.0-rc1-syzkaller-00021-g962490525cff #0

Fixes: cb73ee40b1 ("net: ip_gre: use erspan key field for tunnel lookup")
Reported-by: syzbot+1c1cf138518bf0c53d68@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/000000000000772f2c0614b66ef7@google.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/20240328112248.1101491-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:27 +02:00
Antoine Tenart
2eeab8c47c gro: fix ownership transfer
commit ed4cccef64 upstream.

If packets are GROed with fraglist they might be segmented later on and
continue their journey in the stack. In skb_segment_list those skbs can
be reused as-is. This is an issue as their destructor was removed in
skb_gro_receive_list but not the reference to their socket, and then
they can't be orphaned. Fix this by also removing the reference to the
socket.

For example this could be observed,

  kernel BUG at include/linux/skbuff.h:3131!  (skb_orphan)
  RIP: 0010:ip6_rcv_core+0x11bc/0x19a0
  Call Trace:
   ipv6_list_rcv+0x250/0x3f0
   __netif_receive_skb_list_core+0x49d/0x8f0
   netif_receive_skb_list_internal+0x634/0xd40
   napi_complete_done+0x1d2/0x7d0
   gro_cell_poll+0x118/0x1f0

A similar construction is found in skb_gro_receive, apply the same
change there.

Fixes: 5e10da5385 ("skbuff: allow 'slow_gro' for skb carring sock reference")
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:26 +02:00
Eric Dumazet
18aae2cb87 netfilter: validate user input for expected length
commit 0c83842df4 upstream.

I got multiple syzbot reports showing old bugs exposed
by BPF after commit 20f2505fb4 ("bpf: Try to avoid kzalloc
in cgroup/{s,g}etsockopt")

setsockopt() @optlen argument should be taken into account
before copying data.

 BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
 BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
 BUG: KASAN: slab-out-of-bounds in do_replace net/ipv4/netfilter/ip_tables.c:1111 [inline]
 BUG: KASAN: slab-out-of-bounds in do_ipt_set_ctl+0x902/0x3dd0 net/ipv4/netfilter/ip_tables.c:1627
Read of size 96 at addr ffff88802cd73da0 by task syz-executor.4/7238

CPU: 1 PID: 7238 Comm: syz-executor.4 Not tainted 6.9.0-rc2-next-20240403-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:488
  kasan_report+0x143/0x180 mm/kasan/report.c:601
  kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
  __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
  copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
  copy_from_sockptr include/linux/sockptr.h:55 [inline]
  do_replace net/ipv4/netfilter/ip_tables.c:1111 [inline]
  do_ipt_set_ctl+0x902/0x3dd0 net/ipv4/netfilter/ip_tables.c:1627
  nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101
  do_sock_setsockopt+0x3af/0x720 net/socket.c:2311
  __sys_setsockopt+0x1ae/0x250 net/socket.c:2334
  __do_sys_setsockopt net/socket.c:2343 [inline]
  __se_sys_setsockopt net/socket.c:2340 [inline]
  __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a
RIP: 0033:0x7fd22067dde9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd21f9ff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fd2207abf80 RCX: 00007fd22067dde9
RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fd2206ca47a R08: 0000000000000001 R09: 0000000000000000
R10: 0000000020000880 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd2207abf80 R15: 00007ffd2d0170d8
 </TASK>

Allocated by task 7238:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
  __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
  kasan_kmalloc include/linux/kasan.h:211 [inline]
  __do_kmalloc_node mm/slub.c:4069 [inline]
  __kmalloc_noprof+0x200/0x410 mm/slub.c:4082
  kmalloc_noprof include/linux/slab.h:664 [inline]
  __cgroup_bpf_run_filter_setsockopt+0xd47/0x1050 kernel/bpf/cgroup.c:1869
  do_sock_setsockopt+0x6b4/0x720 net/socket.c:2293
  __sys_setsockopt+0x1ae/0x250 net/socket.c:2334
  __do_sys_setsockopt net/socket.c:2343 [inline]
  __se_sys_setsockopt net/socket.c:2340 [inline]
  __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

The buggy address belongs to the object at ffff88802cd73da0
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 allocated 1-byte region [ffff88802cd73da0, ffff88802cd73da1)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802cd73020 pfn:0x2cd73
flags: 0xfff80000000000(node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffefff(slab)
raw: 00fff80000000000 ffff888015041280 dead000000000100 dead000000000122
raw: ffff88802cd73020 000000008080007f 00000001ffffefff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5103, tgid 2119833701 (syz-executor.4), ts 5103, free_ts 70804600828
  set_page_owner include/linux/page_owner.h:32 [inline]
  post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1490
  prep_new_page mm/page_alloc.c:1498 [inline]
  get_page_from_freelist+0x2e7e/0x2f40 mm/page_alloc.c:3454
  __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4712
  __alloc_pages_node_noprof include/linux/gfp.h:244 [inline]
  alloc_pages_node_noprof include/linux/gfp.h:271 [inline]
  alloc_slab_page+0x5f/0x120 mm/slub.c:2249
  allocate_slab+0x5a/0x2e0 mm/slub.c:2412
  new_slab mm/slub.c:2465 [inline]
  ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3615
  __slab_alloc+0x58/0xa0 mm/slub.c:3705
  __slab_alloc_node mm/slub.c:3758 [inline]
  slab_alloc_node mm/slub.c:3936 [inline]
  __do_kmalloc_node mm/slub.c:4068 [inline]
  kmalloc_node_track_caller_noprof+0x286/0x450 mm/slub.c:4089
  kstrdup+0x3a/0x80 mm/util.c:62
  device_rename+0xb5/0x1b0 drivers/base/core.c:4558
  dev_change_name+0x275/0x860 net/core/dev.c:1232
  do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2864
  __rtnl_newlink net/core/rtnetlink.c:3680 [inline]
  rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3727
  rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6594
  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2559
  netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
  netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
page last free pid 5146 tgid 5146 stack trace:
  reset_page_owner include/linux/page_owner.h:25 [inline]
  free_pages_prepare mm/page_alloc.c:1110 [inline]
  free_unref_page+0xd3c/0xec0 mm/page_alloc.c:2617
  discard_slab mm/slub.c:2511 [inline]
  __put_partials+0xeb/0x130 mm/slub.c:2980
  put_cpu_partial+0x17c/0x250 mm/slub.c:3055
  __slab_free+0x2ea/0x3d0 mm/slub.c:4254
  qlink_free mm/kasan/quarantine.c:163 [inline]
  qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
  kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
  __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
  kasan_slab_alloc include/linux/kasan.h:201 [inline]
  slab_post_alloc_hook mm/slub.c:3888 [inline]
  slab_alloc_node mm/slub.c:3948 [inline]
  __do_kmalloc_node mm/slub.c:4068 [inline]
  __kmalloc_node_noprof+0x1d7/0x450 mm/slub.c:4076
  kmalloc_node_noprof include/linux/slab.h:681 [inline]
  kvmalloc_node_noprof+0x72/0x190 mm/util.c:634
  bucket_table_alloc lib/rhashtable.c:186 [inline]
  rhashtable_rehash_alloc+0x9e/0x290 lib/rhashtable.c:367
  rht_deferred_worker+0x4e1/0x2440 lib/rhashtable.c:427
  process_one_work kernel/workqueue.c:3218 [inline]
  process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3299
  worker_thread+0x86d/0xd70 kernel/workqueue.c:3380
  kthread+0x2f0/0x390 kernel/kthread.c:388
  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

Memory state around the buggy address:
 ffff88802cd73c80: 07 fc fc fc 05 fc fc fc 05 fc fc fc fa fc fc fc
 ffff88802cd73d00: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
>ffff88802cd73d80: fa fc fc fc 01 fc fc fc fa fc fc fc fa fc fc fc
                               ^
 ffff88802cd73e00: fa fc fc fc fa fc fc fc 05 fc fc fc 07 fc fc fc
 ffff88802cd73e80: 07 fc fc fc 07 fc fc fc 07 fc fc fc 07 fc fc fc

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/r/20240404122051.2303764-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:25 +02:00
Florian Westphal
7d0567842b inet: inet_defrag: prevent sk release while still in use
[ Upstream commit 18685451fc ]

ip_local_out() and other functions can pass skb->sk as function argument.

If the skb is a fragment and reassembly happens before such function call
returns, the sk must not be released.

This affects skb fragments reassembled via netfilter or similar
modules, e.g. openvswitch or ct_act.c, when run as part of tx pipeline.

Eric Dumazet made an initial analysis of this bug.  Quoting Eric:
  Calling ip_defrag() in output path is also implying skb_orphan(),
  which is buggy because output path relies on sk not disappearing.

  A relevant old patch about the issue was :
  8282f27449 ("inet: frag: Always orphan skbs inside ip_defrag()")

  [..]

  net/ipv4/ip_output.c depends on skb->sk being set, and probably to an
  inet socket, not an arbitrary one.

  If we orphan the packet in ipvlan, then downstream things like FQ
  packet scheduler will not work properly.

  We need to change ip_defrag() to only use skb_orphan() when really
  needed, ie whenever frag_list is going to be used.

Eric suggested to stash sk in fragment queue and made an initial patch.
However there is a problem with this:

If skb is refragmented again right after, ip_do_fragment() will copy
head->sk to the new fragments, and sets up destructor to sock_wfree.
IOW, we have no choice but to fix up sk_wmem accouting to reflect the
fully reassembled skb, else wmem will underflow.

This change moves the orphan down into the core, to last possible moment.
As ip_defrag_offset is aliased with sk_buff->sk member, we must move the
offset into the FRAG_CB, else skb->sk gets clobbered.

This allows to delay the orphaning long enough to learn if the skb has
to be queued or if the skb is completing the reasm queue.

In the former case, things work as before, skb is orphaned.  This is
safe because skb gets queued/stolen and won't continue past reasm engine.

In the latter case, we will steal the skb->sk reference, reattach it to
the head skb, and fix up wmem accouting when inet_frag inflates truesize.

Fixes: 7026b1ddb6 ("netfilter: Pass socket pointer down through okfn().")
Diagnosed-by: Eric Dumazet <edumazet@google.com>
Reported-by: xingwei lee <xrivendell7@gmail.com>
Reported-by: yue sun <samsun1006219@gmail.com>
Reported-by: syzbot+e5167d7144a62715044c@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240326101845.30836-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-10 16:28:23 +02:00
Eric Dumazet
91b243de91 tcp: properly terminate timers for kernel sockets
[ Upstream commit 151c9c724d ]

We had various syzbot reports about tcp timers firing after
the corresponding netns has been dismantled.

Fortunately Josef Bacik could trigger the issue more often,
and could test a patch I wrote two years ago.

When TCP sockets are closed, we call inet_csk_clear_xmit_timers()
to 'stop' the timers.

inet_csk_clear_xmit_timers() can be called from any context,
including when socket lock is held.
This is the reason it uses sk_stop_timer(), aka del_timer().
This means that ongoing timers might finish much later.

For user sockets, this is fine because each running timer
holds a reference on the socket, and the user socket holds
a reference on the netns.

For kernel sockets, we risk that the netns is freed before
timer can complete, because kernel sockets do not hold
reference on the netns.

This patch adds inet_csk_clear_xmit_timers_sync() function
that using sk_stop_timer_sync() to make sure all timers
are terminated before the kernel socket is released.
Modules using kernel sockets close them in their netns exit()
handler.

Also add sock_not_owned_by_me() helper to get LOCKDEP
support : inet_csk_clear_xmit_timers_sync() must not be called
while socket lock is held.

It is very possible we can revert in the future commit
3a58f13a88 ("net: rds: acquire refcount on TCP sockets")
which attempted to solve the issue in rds only.
(net/smc/af_smc.c and net/mptcp/subflow.c have similar code)

We probably can remove the check_net() tests from
tcp_out_of_resources() and __tcp_close() in the future.

Reported-by: Josef Bacik <josef@toxicpanda.com>
Closes: https://lore.kernel.org/netdev/20240314210740.GA2823176@perftesting/
Fixes: 26abe14379 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.")
Fixes: 8a68173691 ("net: sk_clone_lock() should only do get_net() if the parent is not a kernel socket")
Link: https://lore.kernel.org/bpf/CANn89i+484ffqb93aQm1N-tjxxvb3WDKX0EbD7318RwRgsatjw@mail.gmail.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Josef Bacik <josef@toxicpanda.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://lore.kernel.org/r/20240322135732.1535772-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-10 16:28:21 +02:00
Tobias Brunner
6af7c8a298 ipv4: raw: Fix sending packets from raw sockets via IPsec tunnels
[ Upstream commit c9b3b81716 ]

Since the referenced commit, the xfrm_inner_extract_output() function
uses the protocol field to determine the address family.  So not setting
it for IPv4 raw sockets meant that such packets couldn't be tunneled via
IPsec anymore.

IPv6 raw sockets are not affected as they already set the protocol since
9c9c9ad5fa ("ipv6: set skb->protocol on tcp, raw and ip6_append_data
genereated skbs").

Fixes: f4796398f2 ("xfrm: Remove inner/outer modes from output path")
Signed-off-by: Tobias Brunner <tobias@strongswan.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/c5d9a947-eb19-4164-ac99-468ea814ce20@strongswan.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:21:00 -04:00
Kuniyuki Iwashima
86d9b04042 tcp: Fix refcnt handling in __inet_hash_connect().
[ Upstream commit 04d9d1fc42 ]

syzbot reported a warning in sk_nulls_del_node_init_rcu().

The commit 66b60b0c8c ("dccp/tcp: Unhash sk from ehash for tb2 alloc
failure after check_estalblished().") tried to fix an issue that an
unconnected socket occupies an ehash entry when bhash2 allocation fails.

In such a case, we need to revert changes done by check_established(),
which does not hold refcnt when inserting socket into ehash.

So, to revert the change, we need to __sk_nulls_add_node_rcu() instead
of sk_nulls_add_node_rcu().

Otherwise, sock_put() will cause refcnt underflow and leak the socket.

[0]:
WARNING: CPU: 0 PID: 23948 at include/net/sock.h:799 sk_nulls_del_node_init_rcu+0x166/0x1a0 include/net/sock.h:799
Modules linked in:
CPU: 0 PID: 23948 Comm: syz-executor.2 Not tainted 6.8.0-rc6-syzkaller-00159-gc055fc00c07b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:sk_nulls_del_node_init_rcu+0x166/0x1a0 include/net/sock.h:799
Code: e8 7f 71 c6 f7 83 fb 02 7c 25 e8 35 6d c6 f7 4d 85 f6 0f 95 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 1b 6d c6 f7 90 <0f> 0b 90 eb b2 e8 10 6d c6 f7 4c 89 e7 be 04 00 00 00 e8 63 e7 d2
RSP: 0018:ffffc900032d7848 EFLAGS: 00010246
RAX: ffffffff89cd0035 RBX: 0000000000000001 RCX: 0000000000040000
RDX: ffffc90004de1000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 1ffff1100439ac26 R08: ffffffff89ccffe3 R09: 1ffff1100439ac28
R10: dffffc0000000000 R11: ffffed100439ac29 R12: ffff888021cd6140
R13: dffffc0000000000 R14: ffff88802a9bf5c0 R15: ffff888021cd6130
FS:  00007f3b823f16c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b823f0ff8 CR3: 000000004674a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __inet_hash_connect+0x140f/0x20b0 net/ipv4/inet_hashtables.c:1139
 dccp_v6_connect+0xcb9/0x1480 net/dccp/ipv6.c:956
 __inet_stream_connect+0x262/0xf30 net/ipv4/af_inet.c:678
 inet_stream_connect+0x65/0xa0 net/ipv4/af_inet.c:749
 __sys_connect_file net/socket.c:2048 [inline]
 __sys_connect+0x2df/0x310 net/socket.c:2065
 __do_sys_connect net/socket.c:2075 [inline]
 __se_sys_connect net/socket.c:2072 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2072
 do_syscall_64+0xf9/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f3b8167dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3b823f10c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f3b817abf80 RCX: 00007f3b8167dda9
RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003
RBP: 00007f3b823f1120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 000000000000000b R14: 00007f3b817abf80 R15: 00007ffd3beb57b8
 </TASK>

Reported-by: syzbot+12c506c1aae251e70449@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=12c506c1aae251e70449
Fixes: 66b60b0c8c ("dccp/tcp: Unhash sk from ehash for tb2 alloc failure after check_estalblished().")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240308201623.65448-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:59 -04:00
Kuniyuki Iwashima
9905a15704 rds: tcp: Fix use-after-free of net in reqsk_timer_handler().
[ Upstream commit 2a750d6a5b ]

syzkaller reported a warning of netns tracker [0] followed by KASAN
splat [1] and another ref tracker warning [1].

syzkaller could not find a repro, but in the log, the only suspicious
sequence was as follows:

  18:26:22 executing program 1:
  r0 = socket$inet6_mptcp(0xa, 0x1, 0x106)
  ...
  connect$inet6(r0, &(0x7f0000000080)={0xa, 0x4001, 0x0, @loopback}, 0x1c) (async)

The notable thing here is 0x4001 in connect(), which is RDS_TCP_PORT.

So, the scenario would be:

  1. unshare(CLONE_NEWNET) creates a per netns tcp listener in
      rds_tcp_listen_init().
  2. syz-executor connect()s to it and creates a reqsk.
  3. syz-executor exit()s immediately.
  4. netns is dismantled.  [0]
  5. reqsk timer is fired, and UAF happens while freeing reqsk.  [1]
  6. listener is freed after RCU grace period.  [2]

Basically, reqsk assumes that the listener guarantees netns safety
until all reqsk timers are expired by holding the listener's refcount.
However, this was not the case for kernel sockets.

Commit 740ea3c4a0 ("tcp: Clean up kernel listener's reqsk in
inet_twsk_purge()") fixed this issue only for per-netns ehash.

Let's apply the same fix for the global ehash.

[0]:
ref_tracker: net notrefcnt@0000000065449cc3 has 1/1 users at
     sk_alloc (./include/net/net_namespace.h:337 net/core/sock.c:2146)
     inet6_create (net/ipv6/af_inet6.c:192 net/ipv6/af_inet6.c:119)
     __sock_create (net/socket.c:1572)
     rds_tcp_listen_init (net/rds/tcp_listen.c:279)
     rds_tcp_init_net (net/rds/tcp.c:577)
     ops_init (net/core/net_namespace.c:137)
     setup_net (net/core/net_namespace.c:340)
     copy_net_ns (net/core/net_namespace.c:497)
     create_new_namespaces (kernel/nsproxy.c:110)
     unshare_nsproxy_namespaces (kernel/nsproxy.c:228 (discriminator 4))
     ksys_unshare (kernel/fork.c:3429)
     __x64_sys_unshare (kernel/fork.c:3496)
     do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
     entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129)
...
WARNING: CPU: 0 PID: 27 at lib/ref_tracker.c:179 ref_tracker_dir_exit (lib/ref_tracker.c:179)

[1]:
BUG: KASAN: slab-use-after-free in inet_csk_reqsk_queue_drop (./include/net/inet_hashtables.h:180 net/ipv4/inet_connection_sock.c:952 net/ipv4/inet_connection_sock.c:966)
Read of size 8 at addr ffff88801b370400 by task swapper/0/0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Call Trace:
 <IRQ>
 dump_stack_lvl (lib/dump_stack.c:107 (discriminator 1))
 print_report (mm/kasan/report.c:378 mm/kasan/report.c:488)
 kasan_report (mm/kasan/report.c:603)
 inet_csk_reqsk_queue_drop (./include/net/inet_hashtables.h:180 net/ipv4/inet_connection_sock.c:952 net/ipv4/inet_connection_sock.c:966)
 reqsk_timer_handler (net/ipv4/inet_connection_sock.c:979 net/ipv4/inet_connection_sock.c:1092)
 call_timer_fn (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/timer.h:127 kernel/time/timer.c:1701)
 __run_timers.part.0 (kernel/time/timer.c:1752 kernel/time/timer.c:2038)
 run_timer_softirq (kernel/time/timer.c:2053)
 __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554)
 irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632 kernel/softirq.c:644)
 sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1076 (discriminator 14))
 </IRQ>

Allocated by task 258 on cpu 0 at 83.612050s:
 kasan_save_stack (mm/kasan/common.c:48)
 kasan_save_track (mm/kasan/common.c:68)
 __kasan_slab_alloc (mm/kasan/common.c:343)
 kmem_cache_alloc (mm/slub.c:3813 mm/slub.c:3860 mm/slub.c:3867)
 copy_net_ns (./include/linux/slab.h:701 net/core/net_namespace.c:421 net/core/net_namespace.c:480)
 create_new_namespaces (kernel/nsproxy.c:110)
 unshare_nsproxy_namespaces (kernel/nsproxy.c:228 (discriminator 4))
 ksys_unshare (kernel/fork.c:3429)
 __x64_sys_unshare (kernel/fork.c:3496)
 do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129)

Freed by task 27 on cpu 0 at 329.158864s:
 kasan_save_stack (mm/kasan/common.c:48)
 kasan_save_track (mm/kasan/common.c:68)
 kasan_save_free_info (mm/kasan/generic.c:643)
 __kasan_slab_free (mm/kasan/common.c:265)
 kmem_cache_free (mm/slub.c:4299 mm/slub.c:4363)
 cleanup_net (net/core/net_namespace.c:456 net/core/net_namespace.c:446 net/core/net_namespace.c:639)
 process_one_work (kernel/workqueue.c:2638)
 worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787)
 kthread (kernel/kthread.c:388)
 ret_from_fork (arch/x86/kernel/process.c:153)
 ret_from_fork_asm (arch/x86/entry/entry_64.S:250)

The buggy address belongs to the object at ffff88801b370000
 which belongs to the cache net_namespace of size 4352
The buggy address is located 1024 bytes inside of
 freed 4352-byte region [ffff88801b370000, ffff88801b371100)

[2]:
WARNING: CPU: 0 PID: 95 at lib/ref_tracker.c:228 ref_tracker_free (lib/ref_tracker.c:228 (discriminator 1))
Modules linked in:
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:ref_tracker_free (lib/ref_tracker.c:228 (discriminator 1))
...
Call Trace:
<IRQ>
 __sk_destruct (./include/net/net_namespace.h:353 net/core/sock.c:2204)
 rcu_core (./arch/x86/include/asm/preempt.h:26 kernel/rcu/tree.c:2165 kernel/rcu/tree.c:2433)
 __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554)
 irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632 kernel/softirq.c:644)
 sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1076 (discriminator 14))
</IRQ>

Reported-by: syzkaller <syzkaller@googlegroups.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Fixes: 467fa15356 ("RDS-TCP: Support multiple RDS-TCP listen endpoints, one per netns.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240308200122.64357-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:58 -04:00
Eric Dumazet
6df9cf77e0 tcp: Fix NEW_SYN_RECV handling in inet_twsk_purge()
[ Upstream commit 1c4e97dd2d ]

inet_twsk_purge() uses rcu to find TIME_WAIT and NEW_SYN_RECV
objects to purge.

These objects use SLAB_TYPESAFE_BY_RCU semantic and need special
care. We need to use refcount_inc_not_zero(&sk->sk_refcnt).

Reuse the existing correct logic I wrote for TIME_WAIT,
because both structures have common locations for
sk_state, sk_family, and netns pointer.

If after the refcount_inc_not_zero() the object fields longer match
the keys, use sock_gen_put(sk) to release the refcount.

Then we can call inet_twsk_deschedule_put() for TIME_WAIT,
inet_csk_reqsk_queue_drop_and_put() for NEW_SYN_RECV sockets,
with BH disabled.

Then we need to restart the loop because we had drop rcu_read_lock().

Fixes: 740ea3c4a0 ("tcp: Clean up kernel listener's reqsk in inet_twsk_purge()")
Link: https://lore.kernel.org/netdev/CANn89iLvFuuihCtt9PME2uS1WJATnf5fKjDToa1WzVnRzHnPfg@mail.gmail.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240308200122.64357-2-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:58 -04:00
Gavrilov Ilia
6bb3c04738 udp: fix incorrect parameter validation in the udp_lib_getsockopt() function
[ Upstream commit 4bb3ba7b74 ]

The 'len' variable can't be negative when assigned the result of
'min_t' because all 'min_t' parameters are cast to unsigned int,
and then the minimum one is chosen.

To fix the logic, check 'len' as read from 'optlen',
where the types of relevant variables are (signed) int.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:42 -04:00
Gavrilov Ilia
6ccbd0227f ipmr: fix incorrect parameter validation in the ip_mroute_getsockopt() function
[ Upstream commit 5c3be3e0eb ]

The 'olr' variable can't be negative when assigned the result of
'min_t' because all 'min_t' parameters are cast to unsigned int,
and then the minimum one is chosen.

To fix the logic, check 'olr' as read from 'optlen',
where the types of relevant variables are (signed) int.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:42 -04:00
Gavrilov Ilia
dcdcf9a717 tcp: fix incorrect parameter validation in the do_tcp_getsockopt() function
[ Upstream commit 716edc9706 ]

The 'len' variable can't be negative when assigned the result of
'min_t' because all 'min_t' parameters are cast to unsigned int,
and then the minimum one is chosen.

To fix the logic, check 'len' as read from 'optlen',
where the types of relevant variables are (signed) int.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:42 -04:00
Eric Dumazet
60044ab848 net: ip_tunnel: make sure to pull inner header in ip_tunnel_rcv()
[ Upstream commit b0ec2abf98 ]

Apply the same fix than ones found in :

8d975c15c0 ("ip6_tunnel: make sure to pull inner header in __ip6_tnl_rcv()")
1ca1ba465e ("geneve: make sure to pull inner header in geneve_rx()")

We have to save skb->network_header in a temporary variable
in order to be able to recompute the network_header pointer
after a pskb_inet_may_pull() call.

pskb_inet_may_pull() makes sure the needed headers are in skb->head.

syzbot reported:
BUG: KMSAN: uninit-value in __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]
 BUG: KMSAN: uninit-value in INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]
 BUG: KMSAN: uninit-value in IP_ECN_decapsulate include/net/inet_ecn.h:302 [inline]
 BUG: KMSAN: uninit-value in ip_tunnel_rcv+0xed9/0x2ed0 net/ipv4/ip_tunnel.c:409
  __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]
  INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]
  IP_ECN_decapsulate include/net/inet_ecn.h:302 [inline]
  ip_tunnel_rcv+0xed9/0x2ed0 net/ipv4/ip_tunnel.c:409
  __ipgre_rcv+0x9bc/0xbc0 net/ipv4/ip_gre.c:389
  ipgre_rcv net/ipv4/ip_gre.c:411 [inline]
  gre_rcv+0x423/0x19f0 net/ipv4/ip_gre.c:447
  gre_rcv+0x2a4/0x390 net/ipv4/gre_demux.c:163
  ip_protocol_deliver_rcu+0x264/0x1300 net/ipv4/ip_input.c:205
  ip_local_deliver_finish+0x2b8/0x440 net/ipv4/ip_input.c:233
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254
  dst_input include/net/dst.h:461 [inline]
  ip_rcv_finish net/ipv4/ip_input.c:449 [inline]
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ip_rcv+0x46f/0x760 net/ipv4/ip_input.c:569
  __netif_receive_skb_one_core net/core/dev.c:5534 [inline]
  __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5648
  netif_receive_skb_internal net/core/dev.c:5734 [inline]
  netif_receive_skb+0x58/0x660 net/core/dev.c:5793
  tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1556
  tun_get_user+0x53b9/0x66e0 drivers/net/tun.c:2009
  tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2055
  call_write_iter include/linux/fs.h:2087 [inline]
  new_sync_write fs/read_write.c:497 [inline]
  vfs_write+0xb6b/0x1520 fs/read_write.c:590
  ksys_write+0x20f/0x4c0 fs/read_write.c:643
  __do_sys_write fs/read_write.c:655 [inline]
  __se_sys_write fs/read_write.c:652 [inline]
  __x64_sys_write+0x93/0xd0 fs/read_write.c:652
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
  __alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
  alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
  alloc_pages+0x1be/0x1e0 mm/mempolicy.c:2204
  skb_page_frag_refill+0x2bf/0x7c0 net/core/sock.c:2909
  tun_build_skb drivers/net/tun.c:1686 [inline]
  tun_get_user+0xe0a/0x66e0 drivers/net/tun.c:1826
  tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2055
  call_write_iter include/linux/fs.h:2087 [inline]
  new_sync_write fs/read_write.c:497 [inline]
  vfs_write+0xb6b/0x1520 fs/read_write.c:590
  ksys_write+0x20f/0x4c0 fs/read_write.c:643
  __do_sys_write fs/read_write.c:655 [inline]
  __se_sys_write fs/read_write.c:652 [inline]
  __x64_sys_write+0x93/0xd0 fs/read_write.c:652
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Fixes: c544193214 ("GRE: Refactor GRE tunneling code.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:41 -04:00
Eric Dumazet
d10dbf722d inet_diag: annotate data-races around inet_diag_table[]
[ Upstream commit e50e10ae5d ]

inet_diag_lock_handler() reads inet_diag_table[proto] locklessly.

Use READ_ONCE()/WRITE_ONCE() annotations to avoid potential issues.

Fixes: d523a328fb ("[INET]: Fix inet_diag dead-lock regression")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:31 -04:00
Florian Westphal
b8afc22a11 netfilter: let reset rules clean out conntrack entries
[ Upstream commit 2954fe60e3 ]

iptables/nftables support responding to tcp packets with tcp resets.

The generated tcp reset packet passes through both output and postrouting
netfilter hooks, but conntrack will never see them because the generated
skb has its ->nfct pointer copied over from the packet that triggered the
reset rule.

If the reset rule is used for established connections, this
may result in the conntrack entry to be around for a very long
time (default timeout is 5 days).

One way to avoid this would be to not copy the nf_conn pointer
so that the rest packet passes through conntrack too.

Problem is that output rules might not have the same conntrack
zone setup as the prerouting ones, so its possible that the
reset skb won't find the correct entry.  Generating a template
entry for the skb seems error prone as well.

Add an explicit "closing" function that switches a confirmed
conntrack entry to closed state and wire this up for tcp.

If the entry isn't confirmed, no action is needed because
the conntrack entry will never be committed to the table.

Reported-by: Russel King <linux@armlinux.org.uk>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 62e7151ae3 ("netfilter: bridge: confirm multicast packets before passing them up the stack")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-06 14:45:08 +00:00
Florian Westphal
ab63de24eb net: ip_tunnel: prevent perpetual headroom growth
[ Upstream commit 5ae1e9922b ]

syzkaller triggered following kasan splat:
BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191
[..]
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
 skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline]
 ___skb_get_hash net/core/flow_dissector.c:1791 [inline]
 __skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856
 skb_get_hash include/linux/skbuff.h:1556 [inline]
 ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748
 ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308
 __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3548 [inline]
 dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349
 dev_queue_xmit include/linux/netdevice.h:3134 [inline]
 neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592
 ...
 ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235
 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323
 ..
 iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831
 ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665
 __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3548 [inline]
 dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
 ...

The splat occurs because skb->data points past skb->head allocated area.
This is because neigh layer does:
  __skb_pull(skb, skb_network_offset(skb));

... but skb_network_offset() returns a negative offset and __skb_pull()
arg is unsigned.  IOW, we skb->data gets "adjusted" by a huge value.

The negative value is returned because skb->head and skb->data distance is
more than 64k and skb->network_header (u16) has wrapped around.

The bug is in the ip_tunnel infrastructure, which can cause
dev->needed_headroom to increment ad infinitum.

The syzkaller reproducer consists of packets getting routed via a gre
tunnel, and route of gre encapsulated packets pointing at another (ipip)
tunnel.  The ipip encapsulation finds gre0 as next output device.

This results in the following pattern:

1). First packet is to be sent out via gre0.
Route lookup found an output device, ipip0.

2).
ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future
output device, rt.dev->needed_headroom (ipip0).

3).
ip output / start_xmit moves skb on to ipip0. which runs the same
code path again (xmit recursion).

4).
Routing step for the post-gre0-encap packet finds gre0 as output device
to use for ipip0 encapsulated packet.

tunl0->needed_headroom is then incremented based on the (already bumped)
gre0 device headroom.

This repeats for every future packet:

gre0->needed_headroom gets inflated because previous packets' ipip0 step
incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0
needed_headroom was increased.

For each subsequent packet, gre/ipip0->needed_headroom grows until
post-expand-head reallocations result in a skb->head/data distance of
more than 64k.

Once that happens, skb->network_header (u16) wraps around when
pskb_expand_head tries to make sure that skb_network_offset() is unchanged
after the headroom expansion/reallocation.

After this skb_network_offset(skb) returns a different (and negative)
result post headroom expansion.

The next trip to neigh layer (or anything else that would __skb_pull the
network header) makes skb->data point to a memory location outside
skb->head area.

v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to
prevent perpetual increase instead of dropping the headroom increment
completely.

Reported-and-tested-by: syzbot+bfde3bef047a81b8fde6@syzkaller.appspotmail.com
Closes: https://groups.google.com/g/syzkaller-bugs/c/fL9G6GtWskY/m/VKk_PR5FBAAJ
Fixes: 243aad830e ("ip_gre: include route header_len in max_headroom calculation")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240220135606.4939-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-06 14:45:06 +00:00
Kuniyuki Iwashima
f119f2325b arp: Prevent overflow in arp_req_get().
commit a7d6027790 upstream.

syzkaller reported an overflown write in arp_req_get(). [0]

When ioctl(SIOCGARP) is issued, arp_req_get() looks up an neighbour
entry and copies neigh->ha to struct arpreq.arp_ha.sa_data.

The arp_ha here is struct sockaddr, not struct sockaddr_storage, so
the sa_data buffer is just 14 bytes.

In the splat below, 2 bytes are overflown to the next int field,
arp_flags.  We initialise the field just after the memcpy(), so it's
not a problem.

However, when dev->addr_len is greater than 22 (e.g. MAX_ADDR_LEN),
arp_netmask is overwritten, which could be set as htonl(0xFFFFFFFFUL)
in arp_ioctl() before calling arp_req_get().

To avoid the overflow, let's limit the max length of memcpy().

Note that commit b5f0de6df6 ("net: dev: Convert sa_data to flexible
array in struct sockaddr") just silenced syzkaller.

[0]:
memcpy: detected field-spanning write (size 16) of single field "r->arp_ha.sa_data" at net/ipv4/arp.c:1128 (size 14)
WARNING: CPU: 0 PID: 144638 at net/ipv4/arp.c:1128 arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128
Modules linked in:
CPU: 0 PID: 144638 Comm: syz-executor.4 Not tainted 6.1.74 #31
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-5 04/01/2014
RIP: 0010:arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128
Code: fd ff ff e8 41 42 de fb b9 0e 00 00 00 4c 89 fe 48 c7 c2 20 6d ab 87 48 c7 c7 80 6d ab 87 c6 05 25 af 72 04 01 e8 5f 8d ad fb <0f> 0b e9 6c fd ff ff e8 13 42 de fb be 03 00 00 00 4c 89 e7 e8 a6
RSP: 0018:ffffc900050b7998 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88803a815000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8641a44a RDI: 0000000000000001
RBP: ffffc900050b7a98 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 203a7970636d656d R12: ffff888039c54000
R13: 1ffff92000a16f37 R14: ffff88803a815084 R15: 0000000000000010
FS:  00007f172bf306c0(0000) GS:ffff88805aa00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f172b3569f0 CR3: 0000000057f12005 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 arp_ioctl+0x33f/0x4b0 net/ipv4/arp.c:1261
 inet_ioctl+0x314/0x3a0 net/ipv4/af_inet.c:981
 sock_do_ioctl+0xdf/0x260 net/socket.c:1204
 sock_ioctl+0x3ef/0x650 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x18e/0x220 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x37/0x90 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x64/0xce
RIP: 0033:0x7f172b262b8d
Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f172bf300b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f172b3abf80 RCX: 00007f172b262b8d
RDX: 0000000020000000 RSI: 0000000000008954 RDI: 0000000000000003
RBP: 00007f172b2d3493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f172b3abf80 R15: 00007f172bf10000
 </TASK>

Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: Bjoern Doebel <doebel@amazon.de>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240215230516.31330-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:26:39 +01:00
Eric Dumazet
b43a4fb42f ipv4: properly combine dev_base_seq and ipv4.dev_addr_genid
[ Upstream commit 081a0e3b0d ]

net->dev_base_seq and ipv4.dev_addr_genid are monotonically increasing.

If we XOR their values, we could miss to detect if both values
were changed with the same amount.

Fixes: 0465277f6b ("ipv4: provide addr and netconf dump consistency info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:36 +01:00
Kuniyuki Iwashima
729bc77af4 dccp/tcp: Unhash sk from ehash for tb2 alloc failure after check_estalblished().
[ Upstream commit 66b60b0c8c ]

syzkaller reported a warning [0] in inet_csk_destroy_sock() with no
repro.

  WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash);

However, the syzkaller's log hinted that connect() failed just before
the warning due to FAULT_INJECTION.  [1]

When connect() is called for an unbound socket, we search for an
available ephemeral port.  If a bhash bucket exists for the port, we
call __inet_check_established() or __inet6_check_established() to check
if the bucket is reusable.

If reusable, we add the socket into ehash and set inet_sk(sk)->inet_num.

Later, we look up the corresponding bhash2 bucket and try to allocate
it if it does not exist.

Although it rarely occurs in real use, if the allocation fails, we must
revert the changes by check_established().  Otherwise, an unconnected
socket could illegally occupy an ehash entry.

Note that we do not put tw back into ehash because sk might have
already responded to a packet for tw and it would be better to free
tw earlier under such memory presure.

[0]:
WARNING: CPU: 0 PID: 350830 at net/ipv4/inet_connection_sock.c:1193 inet_csk_destroy_sock (net/ipv4/inet_connection_sock.c:1193)
Modules linked in:
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:inet_csk_destroy_sock (net/ipv4/inet_connection_sock.c:1193)
Code: 41 5c 41 5d 41 5e e9 2d 4a 3d fd e8 28 4a 3d fd 48 89 ef e8 f0 cd 7d ff 5b 5d 41 5c 41 5d 41 5e e9 13 4a 3d fd e8 0e 4a 3d fd <0f> 0b e9 61 fe ff ff e8 02 4a 3d fd 4c 89 e7 be 03 00 00 00 e8 05
RSP: 0018:ffffc9000b21fd38 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000009e78 RCX: ffffffff840bae40
RDX: ffff88806e46c600 RSI: ffffffff840bb012 RDI: ffff88811755cca8
RBP: ffff88811755c880 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000009e78 R11: 0000000000000000 R12: ffff88811755c8e0
R13: ffff88811755c892 R14: ffff88811755c918 R15: 0000000000000000
FS:  00007f03e5243800(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32f21000 CR3: 0000000112ffe001 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
 <TASK>
 ? inet_csk_destroy_sock (net/ipv4/inet_connection_sock.c:1193)
 dccp_close (net/dccp/proto.c:1078)
 inet_release (net/ipv4/af_inet.c:434)
 __sock_release (net/socket.c:660)
 sock_close (net/socket.c:1423)
 __fput (fs/file_table.c:377)
 __fput_sync (fs/file_table.c:462)
 __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
 do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129)
RIP: 0033:0x7f03e53852bb
Code: 03 00 00 00 0f 05 48 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 43 c9 f5 ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 c9 f5 ff 8b 44
RSP: 002b:00000000005dfba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f03e53852bb
RDX: 0000000000000002 RSI: 0000000000000002 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000167c
R10: 0000000008a79680 R11: 0000000000000293 R12: 00007f03e4e43000
R13: 00007f03e4e43170 R14: 00007f03e4e43178 R15: 00007f03e4e43170
 </TASK>

[1]:
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 PID: 350833 Comm: syz-executor.1 Not tainted 6.7.0-12272-g2121c43f88f5 #9
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl (lib/dump_stack.c:107 (discriminator 1))
 should_fail_ex (lib/fault-inject.c:52 lib/fault-inject.c:153)
 should_failslab (mm/slub.c:3748)
 kmem_cache_alloc (mm/slub.c:3763 mm/slub.c:3842 mm/slub.c:3867)
 inet_bind2_bucket_create (net/ipv4/inet_hashtables.c:135)
 __inet_hash_connect (net/ipv4/inet_hashtables.c:1100)
 dccp_v4_connect (net/dccp/ipv4.c:116)
 __inet_stream_connect (net/ipv4/af_inet.c:676)
 inet_stream_connect (net/ipv4/af_inet.c:747)
 __sys_connect_file (net/socket.c:2048 (discriminator 2))
 __sys_connect (net/socket.c:2065)
 __x64_sys_connect (net/socket.c:2072)
 do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129)
RIP: 0033:0x7f03e5284e5d
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48
RSP: 002b:00007f03e4641cc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00000000004bbf80 RCX: 00007f03e5284e5d
RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000004bbf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 000000000000000b R14: 00007f03e52e5530 R15: 0000000000000000
 </TASK>

Reported-by: syzkaller <syzkaller@googlegroups.com>
Fixes: 28044fc1d4 ("net: Add a bhash2 table hashed by port and address")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:36 +01:00
Eric Dumazet
5453875221 inet: read sk->sk_family once in inet_recv_error()
[ Upstream commit eef00a82c5 ]

inet_recv_error() is called without holding the socket lock.

IPv6 socket could mutate to IPv4 with IPV6_ADDRFORM
socket option and trigger a KCSAN warning.

Fixes: f4713a3dfa ("net-timestamp: make tcp_recvmsg call ipv6_recv_error for AF_INET6 socks")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:27 +01:00
Antoine Tenart
e37cde7a57 tunnels: fix out of bounds access when building IPv6 PMTU error
[ Upstream commit d75abeec40 ]

If the ICMPv6 error is built from a non-linear skb we get the following
splat,

  BUG: KASAN: slab-out-of-bounds in do_csum+0x220/0x240
  Read of size 4 at addr ffff88811d402c80 by task netperf/820
  CPU: 0 PID: 820 Comm: netperf Not tainted 6.8.0-rc1+ #543
  ...
   kasan_report+0xd8/0x110
   do_csum+0x220/0x240
   csum_partial+0xc/0x20
   skb_tunnel_check_pmtu+0xeb9/0x3280
   vxlan_xmit_one+0x14c2/0x4080
   vxlan_xmit+0xf61/0x5c00
   dev_hard_start_xmit+0xfb/0x510
   __dev_queue_xmit+0x7cd/0x32a0
   br_dev_queue_push_xmit+0x39d/0x6a0

Use skb_checksum instead of csum_partial who cannot deal with non-linear
SKBs.

Fixes: 4cb47a8644 ("tunnels: PMTU discovery support for directly bridged IP packets")
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:26 +01:00
Zhipeng Lu
fde3d47efe net: ipv4: fix a memleak in ip_setup_cork
[ Upstream commit 5dee6d6923 ]

When inetdev_valid_mtu fails, cork->opt should be freed if it is
allocated in ip_setup_cork. Otherwise there could be a memleak.

Fixes: 501a90c945 ("inet: protect against too small mtu values.")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240129091017.2938835-1-alexious@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:02 +00:00
Eric Dumazet
b383d4ea27 tcp: add sanity checks to rx zerocopy
[ Upstream commit 577e4432f3 ]

TCP rx zerocopy intent is to map pages initially allocated
from NIC drivers, not pages owned by a fs.

This patch adds to can_map_frag() these additional checks:

- Page must not be a compound one.
- page->mapping must be NULL.

This fixes the panic reported by ZhangPeng.

syzbot was able to loopback packets built with sendfile(),
mapping pages owned by an ext4 file to TCP rx zerocopy.

r3 = socket$inet_tcp(0x2, 0x1, 0x0)
mmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0)
r4 = socket$inet_tcp(0x2, 0x1, 0x0)
bind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10)
connect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10)
r5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00',
    0x181e42, 0x0)
fallocate(r5, 0x0, 0x0, 0x85b8)
sendfile(r4, r5, 0x0, 0x8ba0)
getsockopt$inet_tcp_TCP_ZEROCOPY_RECEIVE(r4, 0x6, 0x23,
    &(0x7f00000001c0)={&(0x7f0000ffb000/0x3000)=nil, 0x3000, 0x0, 0x0, 0x0,
    0x0, 0x0, 0x0, 0x0}, &(0x7f0000000440)=0x40)
r6 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00',
    0x181e42, 0x0)

Fixes: 93ab6cc691 ("tcp: implement mmap() for zero copy receive")
Link: https://lore.kernel.org/netdev/5106a58e-04da-372a-b836-9d3d0bd2507b@huawei.com/T/
Reported-and-bisected-by: ZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: linux-mm@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:01 +00:00
Nicolas Dichtel
d2f1b7fe74 ipmr: fix kernel panic when forwarding mcast packets
[ Upstream commit e622502c31 ]

The stacktrace was:
[   86.305548] BUG: kernel NULL pointer dereference, address: 0000000000000092
[   86.306815] #PF: supervisor read access in kernel mode
[   86.307717] #PF: error_code(0x0000) - not-present page
[   86.308624] PGD 0 P4D 0
[   86.309091] Oops: 0000 [#1] PREEMPT SMP NOPTI
[   86.309883] CPU: 2 PID: 3139 Comm: pimd Tainted: G     U             6.8.0-6wind-knet #1
[   86.311027] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
[   86.312728] RIP: 0010:ip_mr_forward (/build/work/knet/net/ipv4/ipmr.c:1985)
[ 86.313399] Code: f9 1f 0f 87 85 03 00 00 48 8d 04 5b 48 8d 04 83 49 8d 44 c5 00 48 8b 40 70 48 39 c2 0f 84 d9 00 00 00 49 8b 46 58 48 83 e0 fe <80> b8 92 00 00 00 00 0f 84 55 ff ff ff 49 83 47 38 01 45 85 e4 0f
[   86.316565] RSP: 0018:ffffad21c0583ae0 EFLAGS: 00010246
[   86.317497] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   86.318596] RDX: ffff9559cb46c000 RSI: 0000000000000000 RDI: 0000000000000000
[   86.319627] RBP: ffffad21c0583b30 R08: 0000000000000000 R09: 0000000000000000
[   86.320650] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
[   86.321672] R13: ffff9559c093a000 R14: ffff9559cc00b800 R15: ffff9559c09c1d80
[   86.322873] FS:  00007f85db661980(0000) GS:ffff955a79d00000(0000) knlGS:0000000000000000
[   86.324291] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   86.325314] CR2: 0000000000000092 CR3: 000000002f13a000 CR4: 0000000000350ef0
[   86.326589] Call Trace:
[   86.327036]  <TASK>
[   86.327434] ? show_regs (/build/work/knet/arch/x86/kernel/dumpstack.c:479)
[   86.328049] ? __die (/build/work/knet/arch/x86/kernel/dumpstack.c:421 /build/work/knet/arch/x86/kernel/dumpstack.c:434)
[   86.328508] ? page_fault_oops (/build/work/knet/arch/x86/mm/fault.c:707)
[   86.329107] ? do_user_addr_fault (/build/work/knet/arch/x86/mm/fault.c:1264)
[   86.329756] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.330350] ? __irq_work_queue_local (/build/work/knet/kernel/irq_work.c:111 (discriminator 1))
[   86.331013] ? exc_page_fault (/build/work/knet/./arch/x86/include/asm/paravirt.h:693 /build/work/knet/arch/x86/mm/fault.c:1515 /build/work/knet/arch/x86/mm/fault.c:1563)
[   86.331702] ? asm_exc_page_fault (/build/work/knet/./arch/x86/include/asm/idtentry.h:570)
[   86.332468] ? ip_mr_forward (/build/work/knet/net/ipv4/ipmr.c:1985)
[   86.333183] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.333920] ipmr_mfc_add (/build/work/knet/./include/linux/rcupdate.h:782 /build/work/knet/net/ipv4/ipmr.c:1009 /build/work/knet/net/ipv4/ipmr.c:1273)
[   86.334583] ? __pfx_ipmr_hash_cmp (/build/work/knet/net/ipv4/ipmr.c:363)
[   86.335357] ip_mroute_setsockopt (/build/work/knet/net/ipv4/ipmr.c:1470)
[   86.336135] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.336854] ? ip_mroute_setsockopt (/build/work/knet/net/ipv4/ipmr.c:1470)
[   86.337679] do_ip_setsockopt (/build/work/knet/net/ipv4/ip_sockglue.c:944)
[   86.338408] ? __pfx_unix_stream_read_actor (/build/work/knet/net/unix/af_unix.c:2862)
[   86.339232] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.339809] ? aa_sk_perm (/build/work/knet/security/apparmor/include/cred.h:153 /build/work/knet/security/apparmor/net.c:181)
[   86.340342] ip_setsockopt (/build/work/knet/net/ipv4/ip_sockglue.c:1415)
[   86.340859] raw_setsockopt (/build/work/knet/net/ipv4/raw.c:836)
[   86.341408] ? security_socket_setsockopt (/build/work/knet/security/security.c:4561 (discriminator 13))
[   86.342116] sock_common_setsockopt (/build/work/knet/net/core/sock.c:3716)
[   86.342747] do_sock_setsockopt (/build/work/knet/net/socket.c:2313)
[   86.343363] __sys_setsockopt (/build/work/knet/./include/linux/file.h:32 /build/work/knet/net/socket.c:2336)
[   86.344020] __x64_sys_setsockopt (/build/work/knet/net/socket.c:2340)
[   86.344766] do_syscall_64 (/build/work/knet/arch/x86/entry/common.c:52 /build/work/knet/arch/x86/entry/common.c:83)
[   86.345433] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.346161] ? syscall_exit_work (/build/work/knet/./include/linux/audit.h:357 /build/work/knet/kernel/entry/common.c:160)
[   86.346938] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.347657] ? syscall_exit_to_user_mode (/build/work/knet/kernel/entry/common.c:215)
[   86.348538] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223)
[   86.349262] ? do_syscall_64 (/build/work/knet/./arch/x86/include/asm/cpufeature.h:171 /build/work/knet/arch/x86/entry/common.c:98)
[   86.349971] entry_SYSCALL_64_after_hwframe (/build/work/knet/arch/x86/entry/entry_64.S:129)

The original packet in ipmr_cache_report() may be queued and then forwarded
with ip_mr_forward(). This last function has the assumption that the skb
dst is set.

After the below commit, the skb dst is dropped by ipv4_pktinfo_prepare(),
which causes the oops.

Fixes: bb7403655b ("ipmr: support IP_PKTINFO on cache report IGMP msg")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240125141847.1931933-1-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:00 +00:00
Eric Dumazet
03dc5b73af ipv4: raw: add drop reasons
[ Upstream commit 42186e6c00 ]

Use existing helpers and drop reason codes for RAW input path.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: e622502c31 ("ipmr: fix kernel panic when forwarding mcast packets")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:00 +00:00
Salvatore Dipietro
90fba981ca tcp: Add memory barrier to tcp_push()
[ Upstream commit 7267e8dcad ]

On CPUs with weak memory models, reads and updates performed by tcp_push
to the sk variables can get reordered leaving the socket throttled when
it should not. The tasklet running tcp_wfree() may also not observe the
memory updates in time and will skip flushing any packets throttled by
tcp_push(), delaying the sending. This can pathologically cause 40ms
extra latency due to bad interactions with delayed acks.

Adding a memory barrier in tcp_push removes the bug, similarly to the
previous commit bf06200e73 ("tcp: tsq: fix nonagle handling").
smp_mb__after_atomic() is used to not incur in unnecessary overhead
on x86 since not affected.

Patch has been tested using an AWS c7g.2xlarge instance with Ubuntu
22.04 and Apache Tomcat 9.0.83 running the basic servlet below:

import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloWorldServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
        response.setContentType("text/html;charset=utf-8");
        OutputStreamWriter osw = new OutputStreamWriter(response.getOutputStream(),"UTF-8");
        String s = "a".repeat(3096);
        osw.write(s,0,s.length());
        osw.flush();
    }
}

Load was applied using wrk2 (https://github.com/kinvolk/wrk2) from an AWS
c6i.8xlarge instance. Before the patch an additional 40ms latency from P99.99+
values is observed while, with the patch, the extra latency disappears.

No patch and tcp_autocorking=1
./wrk -t32 -c128 -d40s --latency -R10000  http://172.31.60.173:8080/hello/hello
  ...
 50.000%    0.91ms
 75.000%    1.13ms
 90.000%    1.46ms
 99.000%    1.74ms
 99.900%    1.89ms
 99.990%   41.95ms  <<< 40+ ms extra latency
 99.999%   48.32ms
100.000%   48.96ms

With patch and tcp_autocorking=1
./wrk -t32 -c128 -d40s --latency -R10000  http://172.31.60.173:8080/hello/hello
  ...
 50.000%    0.90ms
 75.000%    1.13ms
 90.000%    1.45ms
 99.000%    1.72ms
 99.900%    1.83ms
 99.990%    2.11ms  <<< no 40+ ms extra latency
 99.999%    2.53ms
100.000%    2.62ms

Patch has been also tested on x86 (m7i.2xlarge instance) which it is not
affected by this issue and the patch doesn't introduce any additional
delay.

Fixes: 7aa5470c2c ("tcp: tsq: move tsq_flags close to sk_wmem_alloc")
Signed-off-by: Salvatore Dipietro <dipiets@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240119190133.43698-1-dipiets@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-31 16:17:05 -08:00