The new name is stored in the transaction metadata, on commit,
the pointers to the old and new names are swapped.
Therefore in abort and commit case we have to free the
pointer in the chain_trans container.
In commit case, the pointer can be used by another cpu that
is currently dumping the renamed chain, thus kfree needs to
happen after waiting for rcu readers to complete.
Fixes: b7263e071a ("netfilter: nf_tables: Allow chain name of up to 255 chars")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
no need to store the name in separate area.
Furthermore, it uses kmalloc but not kfree and most accesses seem to treat
it as char[IFNAMSIZ] not char *.
Remove this and use dev->name instead.
In case event zeroed dev, just omit the name in the dump.
Fixes: d92191aa84 ("netfilter: nf_tables: cache device name in flowtable object")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
SMC ioctl processing requires the sock lock to work properly in
all thinkable scenarios.
Problem has been found with RaceFuzzer and fixes:
KASAN: null-ptr-deref Read in smc_ioctl
Reported-by: Byoungyoung Lee <lifeasageek@gmail.com>
Reported-by: syzbot+35b2c5aa76fd398b9fd4@syzkaller.appspotmail.com
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric reported that reverting the patch that fixed and simplified IPv6
multipath routes means reverting back to invalid userspace notifications.
eg.,
$ ip -6 route add 2001:db8:1::/64 nexthop dev eth0 nexthop dev eth1
only generates a single notification:
2001:db8:1::/64 dev eth0 metric 1024 pref medium
While working on a fix for this problem I found another case that is just
broken completely - a multipath route with a gateway followed by device
followed by gateway:
$ ip -6 ro add 2001:db8:103::/64
nexthop via 2001:db8:1::64
nexthop dev dummy2
nexthop via 2001:db8:3::64
In this case the device only route is dropped completely - no notification
to userpsace but no addition to the FIB either:
$ ip -6 ro ls
2001:db8:1::/64 dev dummy1 proto kernel metric 256 pref medium
2001:db8:2::/64 dev dummy2 proto kernel metric 256 pref medium
2001:db8:3::/64 dev dummy3 proto kernel metric 256 pref medium
2001:db8:103::/64 metric 1024
nexthop via 2001:db8:1::64 dev dummy1 weight 1
nexthop via 2001:db8:3::64 dev dummy3 weight 1 pref medium
fe80::/64 dev dummy1 proto kernel metric 256 pref medium
fe80::/64 dev dummy2 proto kernel metric 256 pref medium
fe80::/64 dev dummy3 proto kernel metric 256 pref medium
Really, IPv6 multipath is just FUBAR'ed beyond repair when it comes to
device only routes, so do not allow it all.
This change will break any scripts relying on the mpath api for insert,
but I don't see any other way to handle the permutations. Besides, since
the routes are added to the FIB as standalone (non-multipath) routes the
kernel is not doing what the user requested, so it might as well tell the
user that.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correct previous bad attempt at allowing sockets to come out of TCP
repair without sending window probes. To avoid changing size of
the repair variable in struct tcp_sock, this lets the decision for
sending probes or not to be made when coming out of repair by
introducing two ways to turn it off.
v2:
* Remove erroneous comment; defines now make behavior clear
Fixes: 70b7ff1302 ("tcp: allow user to create repair socket without window probes")
Signed-off-by: Stefan Baranoff <sbaranoff@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit adc176c547 ("ipv6 addrconf: Implemented enhanced DAD (RFC7527)")
added enhanced DAD with a nonce length of 6 bytes. However, RFC7527
doesn't specify the length of the nonce, other than being 6 + 8*k bytes,
with integer k >= 0 (RFC3971 5.3.2). The current implementation simply
assumes that the nonce will always be 6 bytes, but others systems are
free to choose different sizes.
If another system sends a nonce of different length but with the same 6
bytes prefix, it shouldn't be considered as the same nonce. Thus, check
that the length of the received nonce is the same as the length we sent.
Ugly scapy test script running on veth0:
def loop():
pkt=sniff(iface="veth0", filter="icmp6", count=1)
pkt = pkt[0]
b = bytearray(pkt[Raw].load)
b[1] += 1
b += b'\xde\xad\xbe\xef\xde\xad\xbe\xef'
pkt[Raw].load = bytes(b)
pkt[IPv6].plen += 8
# fixup checksum after modifying the payload
pkt[IPv6].payload.cksum -= 0x3b44
if pkt[IPv6].payload.cksum < 0:
pkt[IPv6].payload.cksum += 0xffff
sendp(pkt, iface="veth0")
This should result in DAD failure for any address added to veth0's peer,
but is currently ignored.
Fixes: adc176c547 ("ipv6 addrconf: Implemented enhanced DAD (RFC7527)")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A KASAN:use-after-free bug was found related to ip6-erspan
while running selftests/net/ip6_gre_headroom.sh
It happens because of following sequence:
- ipv6hdr pointer is obtained from skb
- skb_cow_head() is called, skb->head memory is reallocated
- old data is accessed using ipv6hdr pointer
skb_cow_head() call was added in e41c7c68ea ("ip6erspan: make sure
enough headroom at xmit."), but looking at the history there was a
chance of similar bug because gre_handle_offloads() and pskb_trim()
can also reallocate skb->head memory. Fixes tag points to commit
which introduced possibility of this bug.
This patch moves ipv6hdr pointer assignment after skb_cow_head() call.
Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the zerocopy sendmsg() path, there are error checks to revert
the zerocopy if we get any error code. syzkaller has discovered
that tls_push_record can return -ECONNRESET, which is fatal, and
happens after the point at which it is safe to revert the iter,
as we've already passed the memory to do_tcp_sendpages.
Previously this code could return -ENOMEM and we would want to
revert the iter, but AFAIK this no longer returns ENOMEM after
a447da7d00 ("tls: fix waitall behavior in tls_sw_recvmsg"),
so we fail for all error codes.
Reported-by: syzbot+c226690f7b3126c5ee04@syzkaller.appspotmail.com
Reported-by: syzbot+709f2810a6a05f11d4d3@syzkaller.appspotmail.com
Signed-off-by: Dave Watson <davejwatson@fb.com>
Fixes: 3c4d755915 ("tls: kernel TLS support")
Signed-off-by: David S. Miller <davem@davemloft.net>
My recent fix for dns_resolver_preparse() printing very long strings was
incomplete, as shown by syzbot which still managed to hit the
WARN_ONCE() in set_precision() by adding a crafted "dns_resolver" key:
precision 50001 too large
WARNING: CPU: 7 PID: 864 at lib/vsprintf.c:2164 vsnprintf+0x48a/0x5a0
The bug this time isn't just a printing bug, but also a logical error
when multiple options ("#"-separated strings) are given in the key
payload. Specifically, when separating an option string into name and
value, if there is no value then the name is incorrectly considered to
end at the end of the key payload, rather than the end of the current
option. This bypasses validation of the option length, and also means
that specifying multiple options is broken -- which presumably has gone
unnoticed as there is currently only one valid option anyway.
A similar problem also applied to option values, as the kstrtoul() when
parsing the "dnserror" option will read past the end of the current
option and into the next option.
Fix these bugs by correctly computing the length of the option name and
by copying the option value, null-terminated, into a temporary buffer.
Reproducer for the WARN_ONCE() that syzbot hit:
perl -e 'print "#A#", "\0" x 50000' | keyctl padd dns_resolver desc @s
Reproducer for "dnserror" option being parsed incorrectly (expected
behavior is to fail when seeing the unknown option "foo", actual
behavior was to read the dnserror value as "1#foo" and fail there):
perl -e 'print "#dnserror=1#foo\0"' | keyctl padd dns_resolver desc @s
Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 4a2d789267 ("DNS: If the DNS server returns an error, allow that to be cached [ver #2]")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This an IPv6 version patch of "ipv4/igmp: init group mode as INCLUDE when
join source group". From RFC3810, part 6.1:
If no per-interface state existed for that
multicast address before the change (i.e., the change consisted of
creating a new per-interface record), or if no state exists after the
change (i.e., the change consisted of deleting a per-interface
record), then the "non-existent" state is considered to have an
INCLUDE filter mode and an empty source list.
Which means a new multicast group should start with state IN(). Currently,
for MLDv2 SSM JOIN_SOURCE_GROUP mode, we first call ipv6_sock_mc_join(),
then ip6_mc_source(), which will trigger a TO_IN() message instead of
ALLOW().
The issue was exposed by commit a052517a8f ("net/multicast: should not
send source list records when have filter mode change"). Before this change,
we sent both ALLOW(A) and TO_IN(A). Now, we only send TO_IN(A).
Fix it by adding a new parameter to init group mode. Also add some wrapper
functions to avoid changing too much code.
v1 -> v2:
In the first version I only cleared the group change record. But this is not
enough. Because when a new group join, it will init as EXCLUDE and trigger
a filter mode change in ip/ip6_mc_add_src(), which will clear all source
addresses sf_crcount. This will prevent early joined address sending state
change records if multi source addressed joined at the same time.
In v2 patch, I fixed it by directly initializing the mode to INCLUDE for SSM
JOIN_SOURCE_GROUP. I also split the original patch into two separated patches
for IPv4 and IPv6.
There is also a difference between v4 and v6 version. For IPv6, when the
interface goes down and up, we will send correct state change record with
unspecified IPv6 address (::) with function ipv6_mc_up(). But after DAD is
completed, we resend the change record TO_IN() in mld_send_initial_cr().
Fix it by sending ALLOW() for INCLUDE mode in mld_send_initial_cr().
Fixes: a052517a8f ("net/multicast: should not send source list records when have filter mode change")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on RFC3376 5.1
If no interface
state existed for that multicast address before the change (i.e., the
change consisted of creating a new per-interface record), or if no
state exists after the change (i.e., the change consisted of deleting
a per-interface record), then the "non-existent" state is considered
to have a filter mode of INCLUDE and an empty source list.
Which means a new multicast group should start with state IN().
Function ip_mc_join_group() works correctly for IGMP ASM(Any-Source Multicast)
mode. It adds a group with state EX() and inits crcount to mc_qrv,
so the kernel will send a TO_EX() report message after adding group.
But for IGMPv3 SSM(Source-specific multicast) JOIN_SOURCE_GROUP mode, we
split the group joining into two steps. First we join the group like ASM,
i.e. via ip_mc_join_group(). So the state changes from IN() to EX().
Then we add the source-specific address with INCLUDE mode. So the state
changes from EX() to IN(A).
Before the first step sends a group change record, we finished the second
step. So we will only send the second change record. i.e. TO_IN(A).
Regarding the RFC stands, we should actually send an ALLOW(A) message for
SSM JOIN_SOURCE_GROUP as the state should mimic the 'IN() to IN(A)'
transition.
The issue was exposed by commit a052517a8f ("net/multicast: should not
send source list records when have filter mode change"). Before this change,
we used to send both ALLOW(A) and TO_IN(A). After this change we only send
TO_IN(A).
Fix it by adding a new parameter to init group mode. Also add new wrapper
functions so we don't need to change too much code.
v1 -> v2:
In my first version I only cleared the group change record. But this is not
enough. Because when a new group join, it will init as EXCLUDE and trigger
an filter mode change in ip/ip6_mc_add_src(), which will clear all source
addresses' sf_crcount. This will prevent early joined address sending state
change records if multi source addressed joined at the same time.
In v2 patch, I fixed it by directly initializing the mode to INCLUDE for SSM
JOIN_SOURCE_GROUP. I also split the original patch into two separated patches
for IPv4 and IPv6.
Fixes: a052517a8f ("net/multicast: should not send source list records when have filter mode change")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After fixing the way DCTCP tracking delayed ACKs, the delayed-ACK
related callbacks are no longer needed
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously, when a data segment was sent an ACK was piggybacked
on the data segment without generating a CA_EVENT_NON_DELAYED_ACK
event to notify congestion control modules. So the DCTCP
ca->delayed_ack_reserved flag could incorrectly stay set when
in fact there were no delayed ACKs being reserved. This could result
in sending a special ECN notification ACK that carries an older
ACK sequence, when in fact there was no need for such an ACK.
DCTCP keeps track of the delayed ACK status with its own separate
state ca->delayed_ack_reserved. Previously it may accidentally cancel
the delayed ACK without updating this field upon sending a special
ACK that carries a older ACK sequence. This inconsistency would
lead to DCTCP receiver never acknowledging the latest data until the
sender times out and retry in some cases.
Packetdrill script (provided by Larry Brakmo)
0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 setsockopt(3, SOL_TCP, TCP_CONGESTION, "dctcp", 5) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0
0.100 < [ect0] SEW 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>
0.100 > SE. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
0.110 < [ect0] . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4
0.200 < [ect0] . 1:1001(1000) ack 1 win 257
0.200 > [ect01] . 1:1(0) ack 1001
0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 1:2(1) ack 1001
0.200 < [ect0] . 1001:2001(1000) ack 2 win 257
0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 2:3(1) ack 2001
0.200 < [ect0] . 2001:3001(1000) ack 3 win 257
0.200 < [ect0] . 3001:4001(1000) ack 3 win 257
0.200 > [ect01] . 3:3(0) ack 4001
0.210 < [ce] P. 4001:4501(500) ack 3 win 257
+0.001 read(4, ..., 4500) = 4500
+0 write(4, ..., 1) = 1
+0 > [ect01] PE. 3:4(1) ack 4501
+0.010 < [ect0] W. 4501:5501(1000) ack 4 win 257
// Previously the ACK sequence below would be 4501, causing a long RTO
+0.040~+0.045 > [ect01] . 4:4(0) ack 5501 // delayed ack
+0.311 < [ect0] . 5501:6501(1000) ack 4 win 257 // More data
+0 > [ect01] . 4:4(0) ack 6501 // now acks everything
+0.500 < F. 9501:9501(0) ack 4 win 257
Reported-by: Larry Brakmo <brakmo@fb.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2018-07-13
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix AF_XDP TX error reporting before final kernel release such that it
becomes consistent between copy mode and zero-copy, from Magnus.
2) Fix three different syzkaller reported issues: oob due to ld_abs
rewrite with too large offset, another oob in l3 based skb test run
and a bug leaving mangled prog in subprog JITing error path, from Daniel.
3) Fix BTF handling for bitfield extraction on big endian, from Okash.
4) Fix a missing linux/errno.h include in cgroup/BPF found by kbuild bot,
from Roman.
5) Fix xdp2skb_meta.sh sample by using just command names instead of
absolute paths for tc and ip and allow them to be redefined, from Taeung.
6) Fix availability probing for BPF seg6 helpers before final kernel ships
so they can be detected at prog load time, from Mathieu.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 8b7008620b ("net: Don't copy pfmemalloc flag in
__copy_skb_header()") introduced a different handling for the
pfmemalloc flag in copy and clone paths.
In __skb_clone(), now, the flag is set only if it was set in the
original skb, but not cleared if it wasn't. This is wrong and
might lead to socket buffers being flagged with pfmemalloc even
if the skb data wasn't allocated from pfmemalloc reserves. Copy
the flag instead of ORing it.
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Fixes: 8b7008620b ("net: Don't copy pfmemalloc flag in __copy_skb_header()")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Tested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch stops returning EMSGSIZE from sendmsg in copy mode when the
size of the packet is larger than the MTU. Just send it to the device
so that it will drop it as in zero-copy mode. This makes the error
reporting consistent between copy mode and zero-copy mode.
Fixes: 35fcde7f8d ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch makes sure ENOBUFS is always returned from sendmsg if there
is no TX queue configured. This was not the case for zero-copy
mode. With this patch this error reporting is consistent between copy
mode and zero-copy mode.
Fixes: ac98d8aab6 ("xsk: wire upp Tx zero-copy functions")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch stops returning EAGAIN in TX copy mode when the completion
queue is full as zero-copy does not do this. Instead this situation
can be detected by comparing the head and tail pointers of the
completion queue in both modes. In any case, EAGAIN was not the
correct error code here since no amount of calling sendmsg will solve
the problem. Only consuming one or more messages on the completion
queue will fix this.
With this patch, the error reporting becomes consistent between copy
mode and zero-copy mode.
Fixes: 35fcde7f8d ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch removes the ENXIO return code from TX copy-mode when
someone has forcefully changed the number of queues on the device so
that the queue bound to the socket is no longer available. Just
silently stop sending anything as in zero-copy mode so the error
reporting gets consistent between the two modes.
Fixes: 35fcde7f8d ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
If variable length link layer headers result in a packet shorter
than dev->hard_header_len, reset the network header offset. Else
skb->mac_len may exceed skb->len after skb_mac_reset_len.
packet_sendmsg_spkt already has similar logic.
Fixes: b84bbaf7a6 ("packet: in packet_snd start writing at link layer allocation")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When pulling the NSH header in nsh_gso_segment, set the mac length
based on the encapsulated packet type.
skb_reset_mac_len computes an offset to the network header, which
here still points to the outer packet:
> skb_reset_network_header(skb);
> [...]
> __skb_pull(skb, nsh_len);
> skb_reset_mac_header(skb); // now mac hdr starts nsh_len == 8B after net hdr
> skb_reset_mac_len(skb); // mac len = net hdr - mac hdr == (u16) -8 == 65528
> [..]
> skb_mac_gso_segment(skb, ..)
Link: http://lkml.kernel.org/r/CAF=yD-KeAcTSOn4AxirAxL8m7QAS8GBBe1w09eziYwvPbbUeYA@mail.gmail.com
Reported-by: syzbot+7b9ed9872dab8c32305d@syzkaller.appspotmail.com
Fixes: c411ed8545 ("nsh: add GSO support")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The pfmemalloc flag indicates that the skb was allocated from
the PFMEMALLOC reserves, and the flag is currently copied on skb
copy and clone.
However, an skb copied from an skb flagged with pfmemalloc
wasn't necessarily allocated from PFMEMALLOC reserves, and on
the other hand an skb allocated that way might be copied from an
skb that wasn't.
So we should not copy the flag on skb copy, and rather decide
whether to allow an skb to be associated with sockets unrelated
to page reclaim depending only on how it was allocated.
Move the pfmemalloc flag before headers_start[0] using an
existing 1-bit hole, so that __copy_skb_header() doesn't copy
it.
When cloning, we'll now take care of this flag explicitly,
contravening to the warning comment of __skb_clone().
While at it, restore the newline usage introduced by commit
b193722731 ("net: reorganize sk_buff for faster
__copy_skb_header()") to visually separate bytes used in
bitfields after headers_start[0], that was gone after commit
a9e419dc7b ("netfilter: merge ctinfo into nfct pointer storage
area"), and describe the pfmemalloc flag in the kernel-doc
structure comment.
This doesn't change the size of sk_buff or cacheline boundaries,
but consolidates the 15 bits hole before tc_index into a 2 bytes
hole before csum, that could now be filled more easily.
Reported-by: Patrick Talbert <ptalbert@redhat.com>
Fixes: c93bdd0e03 ("netvm: allow skb allocation to use PFMEMALLOC reserves")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Under rare conditions where repair code may be used it is possible that
window probes are either unnecessary or undesired. If the user knows that
window probes are not wanted or needed this change allows them to skip
sending them when a socket comes out of repair.
Signed-off-by: Stefan Baranoff <sbaranoff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes a bug where the sequence numbers of a socket created using
TCP repair functionality are lower than set after connect is called.
This occurs when the repair socket overlaps with a TIME-WAIT socket and
triggers the re-use code. The amount lower is equal to the number of times
that a particular IP/port set is re-used and then put back into TIME-WAIT.
Re-using the first time the sequence number is 1 lower, closing that socket
and then re-opening (with repair) a new socket with the same addresses/ports
puts the sequence number 2 lower than set via setsockopt. The third time is
3 lower, etc. I have not tested what the limit of this acrewal is, if any.
The fix is, if a socket is in repair mode, to respect the already set
sequence number and timestamp when it would have already re-used the
TIME-WAIT socket.
Signed-off-by: Stefan Baranoff <sbaranoff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stefan Schmidt says:
====================
pull-request: ieee802154 for net 2018-07-11
An update from ieee802154 for your *net* tree.
Build system fix for a missing include from Arnd Bergmann.
Setting the IFLA_LINK for the lowpan parent from Lubomir Rintel.
Fixes for some RX corner cases in adf7242 driver by Michael Hennerich.
And some small patches to cleanup our BUG_ON vs WARN_ON usage.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
sykzaller triggered several panics similar to the below:
[...]
[ 248.851531] BUG: KASAN: use-after-free in _copy_to_user+0x5c/0x90
[ 248.857656] Read of size 985 at addr ffff8808017ffff2 by task a.out/1425
[...]
[ 248.865902] CPU: 1 PID: 1425 Comm: a.out Not tainted 4.18.0-rc4+ #13
[ 248.865903] Hardware name: Supermicro SYS-5039MS-H12TRF/X11SSE-F, BIOS 2.1a 03/08/2018
[ 248.865905] Call Trace:
[ 248.865910] dump_stack+0xd6/0x185
[ 248.865911] ? show_regs_print_info+0xb/0xb
[ 248.865913] ? printk+0x9c/0xc3
[ 248.865915] ? kmsg_dump_rewind_nolock+0xe4/0xe4
[ 248.865919] print_address_description+0x6f/0x270
[ 248.865920] kasan_report+0x25b/0x380
[ 248.865922] ? _copy_to_user+0x5c/0x90
[ 248.865924] check_memory_region+0x137/0x190
[ 248.865925] kasan_check_read+0x11/0x20
[ 248.865927] _copy_to_user+0x5c/0x90
[ 248.865930] bpf_test_finish.isra.8+0x4f/0xc0
[ 248.865932] bpf_prog_test_run_skb+0x6a0/0xba0
[...]
After scrubbing the BPF prog a bit from the noise, turns out it called
bpf_skb_change_head() for the lwt_xmit prog with headroom of 2. Nothing
wrong in that, however, this was run with repeat >> 0 in bpf_prog_test_run_skb()
and the same skb thus keeps changing until the pskb_expand_head() called
from skb_cow() keeps bailing out in atomic alloc context with -ENOMEM.
So upon return we'll basically have 0 headroom left yet blindly do the
__skb_push() of 14 bytes and keep copying data from there in bpf_test_finish()
out of bounds. Fix to check if we have enough headroom and if pskb_expand_head()
fails, bail out with error.
Another bug independent of this fix (but related in triggering above) is
that BPF_PROG_TEST_RUN should be reworked to reset the skb/xdp buffer to
it's original state from input as otherwise repeating the same test in a
loop won't work for benchmarking when underlying input buffer is getting
changed by the prog each time and reused for the next run leading to
unexpected results.
Fixes: 1cf1cae963 ("bpf: introduce BPF_PROG_TEST_RUN command")
Reported-by: syzbot+709412e651e55ed96498@syzkaller.appspotmail.com
Reported-by: syzbot+54f39d6ab58f39720a55@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_lwt_seg6_* helpers require CONFIG_IPV6_SEG6_BPF, and currently
return -EOPNOTSUPP to indicate unavailability. This patch forces the
BPF verifier to reject programs using these helpers when
!CONFIG_IPV6_SEG6_BPF, allowing users to more easily probe if they are
available or not.
Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Mark reported that syzkaller triggered a KASAN detected slab-out-of-bounds
bug in ___bpf_prog_run() with a BPF_LD | BPF_ABS word load at offset 0x8001.
After further investigation it became clear that the issue was the
BPF_LDX_MEM() which takes offset as an argument whereas it cannot encode
larger than S16_MAX offsets into it. For this synthetical case we need to
move the full address into tmp register instead and do the LDX without
immediate value.
Fixes: e0cea7ce98 ("bpf: implement ld_abs/ld_ind in native bpf")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree:
1) Missing module autoloadfor icmp and icmpv6 x_tables matches,
from Florian Westphal.
2) Possible non-linear access to TCP header from tproxy, from
Mate Eckl.
3) Do not allow rbtree to be used for single elements, this patch
moves all set backend into one single module since such thing
can only happen if hashtable module is explicitly blacklisted,
which should not ever be done.
4) Reject error and standard targets from nft_compat for sanity
reasons, they are never used from there.
5) Don't crash on double hashsize module parameter, from Andrey
Ryabinin.
6) Drop dst on skb before placing it in the fragmentation
reassembly queue, from Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet reports:
Here is a reproducer of an annoying bug detected by syzkaller on our production kernel
[..]
./b78305423 enable_conntrack
Then :
sleep 60
dmesg | tail -10
[ 171.599093] unregister_netdevice: waiting for lo to become free. Usage count = 2
[ 181.631024] unregister_netdevice: waiting for lo to become free. Usage count = 2
[ 191.687076] unregister_netdevice: waiting for lo to become free. Usage count = 2
[ 201.703037] unregister_netdevice: waiting for lo to become free. Usage count = 2
[ 211.711072] unregister_netdevice: waiting for lo to become free. Usage count = 2
[ 221.959070] unregister_netdevice: waiting for lo to become free. Usage count = 2
Reproducer sends ipv6 fragment that hits nfct defrag via LOCAL_OUT hook.
skb gets queued until frag timer expiry -- 1 minute.
Normally nf_conntrack_reasm gets called during prerouting, so skb has
no dst yet which might explain why this wasn't spotted earlier.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: John Sperbeck <jsperbeck@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Loading the nf_conntrack module with doubled hashsize parameter, i.e.
modprobe nf_conntrack hashsize=12345 hashsize=12345
causes NULL-ptr deref.
If 'hashsize' specified twice, the nf_conntrack_set_hashsize() function
will be called also twice.
The first nf_conntrack_set_hashsize() call will set the
'nf_conntrack_htable_size' variable:
nf_conntrack_set_hashsize()
...
/* On boot, we can set this without any fancy locking. */
if (!nf_conntrack_htable_size)
return param_set_uint(val, kp);
But on the second invocation, the nf_conntrack_htable_size is already set,
so the nf_conntrack_set_hashsize() will take a different path and call
the nf_conntrack_hash_resize() function. Which will crash on the attempt
to dereference 'nf_conntrack_hash' pointer:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
RIP: 0010:nf_conntrack_hash_resize+0x255/0x490 [nf_conntrack]
Call Trace:
nf_conntrack_set_hashsize+0xcd/0x100 [nf_conntrack]
parse_args+0x1f9/0x5a0
load_module+0x1281/0x1a50
__se_sys_finit_module+0xbe/0xf0
do_syscall_64+0x7c/0x390
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fix this, by checking !nf_conntrack_hash instead of
!nf_conntrack_htable_size. nf_conntrack_hash will be initialized only
after the module loaded, so the second invocation of the
nf_conntrack_set_hashsize() won't crash, it will just reinitialize
nf_conntrack_htable_size again.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
iptables-nft never requests these, but make this explicitly illegal.
If it were quested, kernel could oops as ->eval is NULL, furthermore,
the builtin targets have no owning module so its possible to rmmod
eb/ip/ip6_tables module even if they would be loaded.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
tcp_zerocopy_receive() relies on tcp_inq() to limit number of bytes
requested by user.
syzbot found that after tcp_disconnect(), tcp_inq() was returning
a stale value (number of bytes in queue before the disconnect).
Note that after this patch, ioctl(fd, SIOCINQ, &val) is also fixed
and returns 0, so this might be a candidate for all known linux kernels.
While we are at this, we probably also should clear urg_data to
avoid other syzkaller reports after it discovers how to deal with
urgent data.
syzkaller repro :
socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3
bind(3, {sa_family=AF_INET, sin_port=htons(20000), sin_addr=inet_addr("224.0.0.1")}, 16) = 0
connect(3, {sa_family=AF_INET, sin_port=htons(20000), sin_addr=inet_addr("127.0.0.1")}, 16) = 0
send(3, ..., 4096, 0) = 4096
connect(3, {sa_family=AF_UNSPEC, sa_data="\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 128) = 0
getsockopt(3, SOL_TCP, TCP_ZEROCOPY_RECEIVE, ..., [16]) = 0 // CRASH
Fixes: 05255b823a ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf 2018-07-07
The following pull-request contains BPF updates for your *net* tree.
Plenty of fixes for different components:
1) A set of critical fixes for sockmap and sockhash, from John Fastabend.
2) fixes for several race conditions in af_xdp, from Magnus Karlsson.
3) hash map refcnt fix, from Mauricio Vasquez.
4) samples/bpf fixes, from Taeung Song.
5) ifup+mtu check for xdp_redirect, from Toshiaki Makita.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting the low threshold to 0 has no effect on frags allocation,
we need to clear high_thresh instead.
The code was pre-existent to commit 648700f76b ("inet: frags:
use rhashtables for reassembly units"), but before the above,
such assignment had a different role: prevent concurrent eviction
from the worker and the netns cleanup helper.
Fixes: 648700f76b ("inet: frags: use rhashtables for reassembly units")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When tcp_diag_destroy closes a TCP_NEW_SYN_RECV socket, it first
frees it by calling inet_csk_reqsk_queue_drop_and_and_put in
tcp_abort, and then frees it again by calling sock_gen_put.
Since tcp_abort only has one caller, and all the other codepaths
in tcp_abort don't free the socket, just remove the free in that
function.
Cc: David Ahern <dsa@cumulusnetworks.com>
Tested: passes Android sock_diag_test.py, which exercises this codepath
Fixes: d7226c7a4d ("net: diag: Fix refcnt leak in error path destroying socket")
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Xin reported that icmp replies may not use the address on the device the
echo request is received if the destination address is broadcast. Instead
a route lookup is done without considering VRF context. Fix by setting
oif in flow struct to the master device if it is enslaved. That directs
the lookup to the VRF table. If the device is not enslaved, oif is still
0 so no affect.
Fixes: cd2fbe1b6b ("net: Use VRF device index for lookups on RX")
Reported-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise we end up with attempting to send packets from down devices
or to send oversized packets, which may cause unexpected driver/device
behaviour. Generic XDP has already done this check, so reuse the logic
in native XDP.
Fixes: 814abfabef ("xdp: add bpf_redirect helper function")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In commit
'bpf: bpf_compute_data uses incorrect cb structure' (8108a77515)
we added the routine bpf_compute_data_end_sk_skb() to compute the
correct data_end values, but this has since been lost. In kernel
v4.14 this was correct and the above patch was applied in it
entirety. Then when v4.14 was merged into v4.15-rc1 net-next tree
we lost the piece that renamed bpf_compute_data_pointers to the
new function bpf_compute_data_end_sk_skb. This was done here,
e1ea2f9856 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net")
When it conflicted with the following rename patch,
6aaae2b6c4 ("bpf: rename bpf_compute_data_end into bpf_compute_data_pointers")
Finally, after a refactor I thought even the function
bpf_compute_data_end_sk_skb() was no longer needed and it was
erroneously removed.
However, we never reverted the sk_skb_convert_ctx_access() usage of
tcp_skb_cb which had been committed and survived the merge conflict.
Here we fix this by adding back the helper and *_data_end_sk_skb()
usage. Using the bpf_skc_data_end mapping is not correct because it
expects a qdisc_skb_cb object but at the sock layer this is not the
case. Even though it happens to work here because we don't overwrite
any data in-use at the socket layer and the cb structure is cleared
later this has potential to create some subtle issues. But, even
more concretely the filter.c access check uses tcp_skb_cb.
And by some act of chance though,
struct bpf_skb_data_end {
struct qdisc_skb_cb qdisc_cb; /* 0 28 */
/* XXX 4 bytes hole, try to pack */
void * data_meta; /* 32 8 */
void * data_end; /* 40 8 */
/* size: 48, cachelines: 1, members: 3 */
/* sum members: 44, holes: 1, sum holes: 4 */
/* last cacheline: 48 bytes */
};
and then tcp_skb_cb,
struct tcp_skb_cb {
[...]
struct {
__u32 flags; /* 24 4 */
struct sock * sk_redir; /* 32 8 */
void * data_end; /* 40 8 */
} bpf; /* 24 */
};
So when we use offset_of() to track down the byte offset we get 40 in
either case and everything continues to work. Fix this mess and use
correct structures its unclear how long this might actually work for
until someone moves the structs around.
Reported-by: Martin KaFai Lau <kafai@fb.com>
Fixes: e1ea2f9856 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net")
Fixes: 6aaae2b6c4 ("bpf: rename bpf_compute_data_end into bpf_compute_data_pointers")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Multiple BPF helpers in use by sk_skb programs calculate the max
skb length using the __bpf_skb_max_len function. However, this
calculates the max length using the skb->dev pointer which can be
NULL when an sk_skb program is paired with an sk_msg program.
To force this a sk_msg program needs to redirect into the ingress
path of a sock with an attach sk_skb program. Then the the sk_skb
program would need to call one of the helpers that adjust the skb
size.
To fix the null ptr dereference use SKB_MAX_ALLOC size if no dev
is available.
Fixes: 8934ce2fd0 ("bpf: sockmap redirect ingress support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
smc_release() calls a sock_put() for smc fallback sockets to cover
the passive closing sock_hold() in __smc_connect() and
smc_tcp_listen_work(). This does not make sense for sockets in state
SMC_LISTEN and SMC_INIT.
An SMC socket stays in state SMC_INIT if connect fails. The sock_put
in smc_connect_abort() does not cover all failures. Move it into
smc_connect_decline_fallback().
Fixes: ee9dfbef02 ("net/smc: handle sockopts forcing fallback")
Reported-by: syzbot+3a0748c8f2f210c0ef9b@syzkaller.appspotmail.com
Reported-by: syzbot+9e60d2428a42049a592a@syzkaller.appspotmail.com
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The setting of the node address is not thread safe, meaning that
two discoverers may decide to set it simultanously, with a duplicate
entry in the name table as result. We fix that with this commit.
Fixes: 25b0b9c4e8 ("tipc: handle collisions of 32-bit node address hash values")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The duplicate address discovery protocol is not safe against two
discoverers running in parallel. The one executing first after the
trial period is over will set the node address and change its own
message type to DSC_REQ_MSG. The one executing last may find that the
node address is already set, and never change message type, with the
result that its links may never be established.
In this commmit we ensure that the message type always is set correctly
after the trial period is over.
Fixes: 25b0b9c4e8 ("tipc: handle collisions of 32-bit node address hash values")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
