Commit graph

2904 commits

Author SHA1 Message Date
Eduard Zingerman
904e6ddf41 bpf: Use scalar ids in mark_chain_precision()
Change mark_chain_precision() to track precision in situations
like below:

    r2 = unknown value
    ...
  --- state #0 ---
    ...
    r1 = r2                 // r1 and r2 now share the same ID
    ...
  --- state #1 {r1.id = A, r2.id = A} ---
    ...
    if (r2 > 10) goto exit; // find_equal_scalars() assigns range to r1
    ...
  --- state #2 {r1.id = A, r2.id = A} ---
    r3 = r10
    r3 += r1                // need to mark both r1 and r2

At the beginning of the processing of each state, ensure that if a
register with a scalar ID is marked as precise, all registers sharing
this ID are also marked as precise.

This property would be used by a follow-up change in regsafe().

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230613153824.3324830-2-eddyz87@gmail.com
2023-06-13 15:14:27 -07:00
David Vernet
f983be9173 bpf: Replace bpf_cpumask_any* with bpf_cpumask_any_distribute*
We currently export the bpf_cpumask_any() and bpf_cpumask_any_and()
kfuncs. Intuitively, one would expect these to choose any CPU in the
cpumask, but what they actually do is alias to cpumask_first() and
cpmkas_first_and().

This is useless given that we already export bpf_cpumask_first() and
bpf_cpumask_first_and(), so this patch replaces them with kfuncs that
call cpumask_any_distribute() and cpumask_any_and_distribute(), which
actually choose any CPU from the cpumask (or the AND of two cpumasks for
the latter).

Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230610035053.117605-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-12 15:09:11 -07:00
David Vernet
5ba3a7a851 bpf: Add bpf_cpumask_first_and() kfunc
We currently provide bpf_cpumask_first(), bpf_cpumask_any(), and
bpf_cpumask_any_and() kfuncs. bpf_cpumask_any() and
bpf_cpumask_any_and() are confusing misnomers in that they actually just
call cpumask_first() and cpumask_first_and() respectively.

We'll replace them with bpf_cpumask_any_distribute() and
bpf_cpumask_any_distribute_and() kfuncs in a subsequent patch, so let's
ensure feature parity by adding a bpf_cpumask_first_and() kfunc to
account for bpf_cpumask_any_and() being removed.

Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230610035053.117605-1-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-12 15:09:11 -07:00
Arnd Bergmann
ba49f97688 bpf: Hide unused bpf_patch_call_args
This function is only used when CONFIG_BPF_JIT_ALWAYS_ON is disabled, but
CONFIG_BPF_SYSCALL is enabled. When both are turned off, the prototype is
missing but the unused function is still compiled, as seen from this W=1
warning:

  [...]
  kernel/bpf/core.c:2075:6: error: no previous prototype for 'bpf_patch_call_args' [-Werror=missing-prototypes]
  [...]

Add a matching #ifdef for the definition to leave it out.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230602135128.1498362-1-arnd@kernel.org
2023-06-12 19:00:08 +02:00
Hou Tao
aa7881fcfe bpf: Factor out a common helper free_all()
Factor out a common helper free_all() to free all normal elements or
per-cpu elements on a lock-less list.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20230606035310.4026145-2-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-06 13:40:07 -07:00
David Vernet
51302c951c bpf: Teach verifier that trusted PTR_TO_BTF_ID pointers are non-NULL
In reg_type_not_null(), we currently assume that a pointer may be NULL
if it has the PTR_MAYBE_NULL modifier, or if it doesn't belong to one of
several base type of pointers that are never NULL-able. For example,
PTR_TO_CTX, PTR_TO_MAP_VALUE, etc.

It turns out that in some cases, PTR_TO_BTF_ID can never be NULL as
well, though we currently don't specify it. For example, if you had the
following program:

SEC("tc")
long example_refcnt_fail(void *ctx)
{
	struct bpf_cpumask *mask1, *mask2;

	mask1 = bpf_cpumask_create();
	mask2 = bpf_cpumask_create();

        if (!mask1 || !mask2)
		goto error_release;

	bpf_cpumask_test_cpu(0, (const struct cpumask *)mask1);
	bpf_cpumask_test_cpu(0, (const struct cpumask *)mask2);

error_release:
	if (mask1)
		bpf_cpumask_release(mask1);
	if (mask2)
		bpf_cpumask_release(mask2);
	return ret;
}

The verifier will incorrectly fail to load the program, thinking
(unintuitively) that we have a possibly-unreleased reference if the mask
is NULL, because we (correctly) don't issue a bpf_cpumask_release() on
the NULL path.

The reason the verifier gets confused is due to the fact that we don't
explicitly tell the verifier that trusted PTR_TO_BTF_ID pointers can
never be NULL. Basically, if we successfully get past the if check
(meaning both pointers go from ptr_or_null_bpf_cpumask to
ptr_bpf_cpumask), the verifier will correctly assume that the references
need to be dropped on any possible branch that leads to program exit.
However, it will _incorrectly_ think that the ptr == NULL branch is
possible, and will erroneously detect it as a branch on which we failed
to drop the reference.

The solution is of course to teach the verifier that trusted
PTR_TO_BTF_ID pointers can never be NULL, so that it doesn't incorrectly
think it's possible for the reference to be present on the ptr == NULL
branch.

A follow-on patch will add a selftest that verifies this behavior.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230602150112.1494194-1-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-05 14:36:57 -07:00
Daniel T. Lee
503e4def54 bpf: Replace open code with for allocated object check
>From commit 282de143ea ("bpf: Introduce allocated objects support"),
With this allocated object with BPF program, (PTR_TO_BTF_ID | MEM_ALLOC)
has been a way of indicating to check the type is the allocated object.

commit d8939cb0a0 ("bpf: Loosen alloc obj test in verifier's
reg_btf_record")
>From the commit, there has been helper function for checking this, named
type_is_ptr_alloc_obj(). But still, some of the code use open code to
retrieve this info. This commit replaces the open code with the
type_is_alloc(), and the type_is_ptr_alloc_obj() function.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230527122706.59315-1-danieltimlee@gmail.com
2023-06-05 14:33:17 -07:00
Dave Marchevsky
7793fc3bab bpf: Make bpf_refcount_acquire fallible for non-owning refs
This patch fixes an incorrect assumption made in the original
bpf_refcount series [0], specifically that the BPF program calling
bpf_refcount_acquire on some node can always guarantee that the node is
alive. In that series, the patch adding failure behavior to rbtree_add
and list_push_{front, back} breaks this assumption for non-owning
references.

Consider the following program:

  n = bpf_kptr_xchg(&mapval, NULL);
  /* skip error checking */

  bpf_spin_lock(&l);
  if(bpf_rbtree_add(&t, &n->rb, less)) {
    bpf_refcount_acquire(n);
    /* Failed to add, do something else with the node */
  }
  bpf_spin_unlock(&l);

It's incorrect to assume that bpf_refcount_acquire will always succeed in this
scenario. bpf_refcount_acquire is being called in a critical section
here, but the lock being held is associated with rbtree t, which isn't
necessarily the lock associated with the tree that the node is already
in. So after bpf_rbtree_add fails to add the node and calls bpf_obj_drop
in it, the program has no ownership of the node's lifetime. Therefore
the node's refcount can be decr'd to 0 at any time after the failing
rbtree_add. If this happens before the refcount_acquire above, the node
might be free'd, and regardless refcount_acquire will be incrementing a
0 refcount.

Later patches in the series exercise this scenario, resulting in the
expected complaint from the kernel (without this patch's changes):

  refcount_t: addition on 0; use-after-free.
  WARNING: CPU: 1 PID: 207 at lib/refcount.c:25 refcount_warn_saturate+0xbc/0x110
  Modules linked in: bpf_testmod(O)
  CPU: 1 PID: 207 Comm: test_progs Tainted: G           O       6.3.0-rc7-02231-g723de1a718a2-dirty #371
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
  RIP: 0010:refcount_warn_saturate+0xbc/0x110
  Code: 6f 64 f6 02 01 e8 84 a3 5c ff 0f 0b eb 9d 80 3d 5e 64 f6 02 00 75 94 48 c7 c7 e0 13 d2 82 c6 05 4e 64 f6 02 01 e8 64 a3 5c ff <0f> 0b e9 7a ff ff ff 80 3d 38 64 f6 02 00 0f 85 6d ff ff ff 48 c7
  RSP: 0018:ffff88810b9179b0 EFLAGS: 00010082
  RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000
  RDX: 0000000000000202 RSI: 0000000000000008 RDI: ffffffff857c3680
  RBP: ffff88810027d3c0 R08: ffffffff8125f2a4 R09: ffff88810b9176e7
  R10: ffffed1021722edc R11: 746e756f63666572 R12: ffff88810027d388
  R13: ffff88810027d3c0 R14: ffffc900005fe030 R15: ffffc900005fe048
  FS:  00007fee0584a700(0000) GS:ffff88811b280000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00005634a96f6c58 CR3: 0000000108ce9002 CR4: 0000000000770ee0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   <TASK>
   bpf_refcount_acquire_impl+0xb5/0xc0

  (rest of output snipped)

The patch addresses this by changing bpf_refcount_acquire_impl to use
refcount_inc_not_zero instead of refcount_inc and marking
bpf_refcount_acquire KF_RET_NULL.

For owning references, though, we know the above scenario is not possible
and thus that bpf_refcount_acquire will always succeed. Some verifier
bookkeeping is added to track "is input owning ref?" for bpf_refcount_acquire
calls and return false from is_kfunc_ret_null for bpf_refcount_acquire on
owning refs despite it being marked KF_RET_NULL.

Existing selftests using bpf_refcount_acquire are modified where
necessary to NULL-check its return value.

  [0]: https://lore.kernel.org/bpf/20230415201811.343116-1-davemarchevsky@fb.com/

Fixes: d2dcc67df9 ("bpf: Migrate bpf_rbtree_add and bpf_list_push_{front,back} to possibly fail")
Reported-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230602022647.1571784-5-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-05 13:17:20 -07:00
Dave Marchevsky
cc0d76cafe bpf: Fix __bpf_{list,rbtree}_add's beginning-of-node calculation
Given the pointer to struct bpf_{rb,list}_node within a local kptr and
the byte offset of that field within the kptr struct, the calculation changed
by this patch is meant to find the beginning of the kptr so that it can
be passed to bpf_obj_drop.

Unfortunately instead of doing

  ptr_to_kptr = ptr_to_node_field - offset_bytes

the calculation is erroneously doing

  ptr_to_ktpr = ptr_to_node_field - (offset_bytes * sizeof(struct bpf_rb_node))

or the bpf_list_node equivalent.

This patch fixes the calculation.

Fixes: d2dcc67df9 ("bpf: Migrate bpf_rbtree_add and bpf_list_push_{front,back} to possibly fail")
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230602022647.1571784-4-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-05 13:17:19 -07:00
Dave Marchevsky
2140a6e342 bpf: Set kptr_struct_meta for node param to list and rbtree insert funcs
In verifier.c, fixup_kfunc_call uses struct bpf_insn_aux_data's
kptr_struct_meta field to pass information about local kptr types to
various helpers and kfuncs at runtime. The recent bpf_refcount series
added a few functions to the set that need this information:

  * bpf_refcount_acquire
    * Needs to know where the refcount field is in order to increment
  * Graph collection insert kfuncs: bpf_rbtree_add, bpf_list_push_{front,back}
    * Were migrated to possibly fail by the bpf_refcount series. If
      insert fails, the input node is bpf_obj_drop'd. bpf_obj_drop needs
      the kptr_struct_meta in order to decr refcount and properly free
      special fields.

Unfortunately the verifier handling of collection insert kfuncs was not
modified to actually populate kptr_struct_meta. Accordingly, when the
node input to those kfuncs is passed to bpf_obj_drop, it is done so
without the information necessary to decr refcount.

This patch fixes the issue by populating kptr_struct_meta for those
kfuncs.

Fixes: d2dcc67df9 ("bpf: Migrate bpf_rbtree_add and bpf_list_push_{front,back} to possibly fail")
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230602022647.1571784-3-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-05 13:17:19 -07:00
Azeem Shaikh
ffadc37252 bpf: Replace all non-returning strlcpy with strscpy
strlcpy() reads the entire source buffer first. This read may exceed the
destination size limit. This is both inefficient and can lead to linear
read overflows if a source string is not NUL-terminated [1]. This is not
the case here, however, in an effort to remove strlcpy() completely [2],
lets replace strlcpy() here with strscpy(). No return values were used,
so a direct replacement is safe.

  [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
  [2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/bpf/20230530155659.309657-1-azeemshaikh38@gmail.com
2023-05-31 13:04:20 +02:00
Yonghong Song
e6c2f594ed bpf: Silence a warning in btf_type_id_size()
syzbot reported a warning in [1] with the following stacktrace:
  WARNING: CPU: 0 PID: 5005 at kernel/bpf/btf.c:1988 btf_type_id_size+0x2d9/0x9d0 kernel/bpf/btf.c:1988
  ...
  RIP: 0010:btf_type_id_size+0x2d9/0x9d0 kernel/bpf/btf.c:1988
  ...
  Call Trace:
   <TASK>
   map_check_btf kernel/bpf/syscall.c:1024 [inline]
   map_create+0x1157/0x1860 kernel/bpf/syscall.c:1198
   __sys_bpf+0x127f/0x5420 kernel/bpf/syscall.c:5040
   __do_sys_bpf kernel/bpf/syscall.c:5162 [inline]
   __se_sys_bpf kernel/bpf/syscall.c:5160 [inline]
   __x64_sys_bpf+0x79/0xc0 kernel/bpf/syscall.c:5160
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd

With the following btf
  [1] DECL_TAG 'a' type_id=4 component_idx=-1
  [2] PTR '(anon)' type_id=0
  [3] TYPE_TAG 'a' type_id=2
  [4] VAR 'a' type_id=3, linkage=static
and when the bpf_attr.btf_key_type_id = 1 (DECL_TAG),
the following WARN_ON_ONCE in btf_type_id_size() is triggered:
  if (WARN_ON_ONCE(!btf_type_is_modifier(size_type) &&
                   !btf_type_is_var(size_type)))
          return NULL;

Note that 'return NULL' is the correct behavior as we don't want
a DECL_TAG type to be used as a btf_{key,value}_type_id even
for the case like 'DECL_TAG -> STRUCT'. So there
is no correctness issue here, we just want to silence warning.

To silence the warning, I added DECL_TAG as one of kinds in
btf_type_nosize() which will cause btf_type_id_size() returning
NULL earlier without the warning.

  [1] https://lore.kernel.org/bpf/000000000000e0df8d05fc75ba86@google.com/

Reported-by: syzbot+958967f249155967d42a@syzkaller.appspotmail.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230530205029.264910-1-yhs@fb.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-30 14:34:46 -07:00
Jakub Kicinski
75455b906d bpf-next-for-netdev
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZHEm+wAKCRDbK58LschI
 gyIKAQCqO7B4sIu8hYVxBTwfHV2tIuXSMSCV4P9e78NUOPcO2QEAvLP/WVSjB0Bm
 vpyTKKM22SpZvPe/jSp52j6t20N+qAc=
 =HFxD
 -----END PGP SIGNATURE-----

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-05-26

We've added 54 non-merge commits during the last 10 day(s) which contain
a total of 76 files changed, 2729 insertions(+), 1003 deletions(-).

The main changes are:

1) Add the capability to destroy sockets in BPF through a new kfunc,
   from Aditi Ghag.

2) Support O_PATH fds in BPF_OBJ_PIN and BPF_OBJ_GET commands,
   from Andrii Nakryiko.

3) Add capability for libbpf to resize datasec maps when backed via mmap,
   from JP Kobryn.

4) Move all the test kfuncs for CI out of the kernel and into bpf_testmod,
   from Jiri Olsa.

5) Big batch of xsk selftest improvements to prep for multi-buffer testing,
   from Magnus Karlsson.

6) Show the target_{obj,btf}_id in tracing link's fdinfo and dump it
   via bpftool, from Yafang Shao.

7) Various misc BPF selftest improvements to work with upcoming LLVM 17,
   from Yonghong Song.

8) Extend bpftool to specify netdevice for resolving XDP hints,
   from Larysa Zaremba.

9) Document masking in shift operations for the insn set document,
   from Dave Thaler.

10) Extend BPF selftests to check xdp_feature support for bond driver,
    from Lorenzo Bianconi.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits)
  bpf: Fix bad unlock balance on freeze_mutex
  libbpf: Ensure FD >= 3 during bpf_map__reuse_fd()
  libbpf: Ensure libbpf always opens files with O_CLOEXEC
  selftests/bpf: Check whether to run selftest
  libbpf: Change var type in datasec resize func
  bpf: drop unnecessary bpf_capable() check in BPF_MAP_FREEZE command
  libbpf: Selftests for resizing datasec maps
  libbpf: Add capability for resizing datasec maps
  selftests/bpf: Add path_fd-based BPF_OBJ_PIN and BPF_OBJ_GET tests
  libbpf: Add opts-based bpf_obj_pin() API and add support for path_fd
  bpf: Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands
  libbpf: Start v1.3 development cycle
  bpf: Validate BPF object in BPF_OBJ_PIN before calling LSM
  bpftool: Specify XDP Hints ifname when loading program
  selftests/bpf: Add xdp_feature selftest for bond device
  selftests/bpf: Test bpf_sock_destroy
  selftests/bpf: Add helper to get port using getsockname
  bpf: Add bpf_sock_destroy kfunc
  bpf: Add kfunc filter function to 'struct btf_kfunc_id_set'
  bpf: udp: Implement batching for sockets iterator
  ...
====================

Link: https://lore.kernel.org/r/20230526222747.17775-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-26 17:26:01 -07:00
Daniel Borkmann
4266f41fea bpf: Fix bad unlock balance on freeze_mutex
Commit c4c84f6fb2 ("bpf: drop unnecessary bpf_capable() check in
BPF_MAP_FREEZE command") moved the permissions check outside of the
freeze_mutex in the map_freeze() handler. The error paths still jumps
to the err_put which tries to unlock the freeze_mutex even though it
was not locked in the first place. Fix it.

Fixes: c4c84f6fb2 ("bpf: drop unnecessary bpf_capable() check in BPF_MAP_FREEZE command")
Reported-by: syzbot+8982e75c2878b9ffeac5@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2023-05-26 12:16:12 +02:00
Jakub Kicinski
d4031ec844 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/ipv4/raw.c
  3632679d9e ("ipv{4,6}/raw: fix output xfrm lookup wrt protocol")
  c85be08fc4 ("raw: Stop using RTO_ONLINK.")
https://lore.kernel.org/all/20230525110037.2b532b83@canb.auug.org.au/

Adjacent changes:

drivers/net/ethernet/freescale/fec_main.c
  9025944fdd ("net: fec: add dma_wmb to ensure correct descriptor values")
  144470c88c ("net: fec: using the standard return codes when xdp xmit errors")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-25 19:57:39 -07:00
Andrii Nakryiko
c4c84f6fb2 bpf: drop unnecessary bpf_capable() check in BPF_MAP_FREEZE command
Seems like that extra bpf_capable() check in BPF_MAP_FREEZE handler was
unintentionally left when we switched to a model that all BPF map
operations should be allowed regardless of CAP_BPF (or any other
capabilities), as long as process got BPF map FD somehow.

This patch replaces bpf_capable() check in BPF_MAP_FREEZE handler with
writeable access check, given conceptually freezing the map is modifying
it: map becomes unmodifiable for subsequent updates.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230524225421.1587859-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-25 10:08:20 -07:00
Andrii Nakryiko
cb8edce280 bpf: Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands
Current UAPI of BPF_OBJ_PIN and BPF_OBJ_GET commands of bpf() syscall
forces users to specify pinning location as a string-based absolute or
relative (to current working directory) path. This has various
implications related to security (e.g., symlink-based attacks), forces
BPF FS to be exposed in the file system, which can cause races with
other applications.

One of the feedbacks we got from folks working with containers heavily
was that inability to use purely FD-based location specification was an
unfortunate limitation and hindrance for BPF_OBJ_PIN and BPF_OBJ_GET
commands. This patch closes this oversight, adding path_fd field to
BPF_OBJ_PIN and BPF_OBJ_GET UAPI, following conventions established by
*at() syscalls for dirfd + pathname combinations.

This now allows interesting possibilities like working with detached BPF
FS mount (e.g., to perform multiple pinnings without running a risk of
someone interfering with them), and generally making pinning/getting
more secure and not prone to any races and/or security attacks.

This is demonstrated by a selftest added in subsequent patch that takes
advantage of new mount APIs (fsopen, fsconfig, fsmount) to demonstrate
creating detached BPF FS mount, pinning, and then getting BPF map out of
it, all while never exposing this private instance of BPF FS to outside
worlds.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/bpf/20230523170013.728457-4-andrii@kernel.org
2023-05-23 23:31:42 +02:00
Andrii Nakryiko
e7d85427ef bpf: Validate BPF object in BPF_OBJ_PIN before calling LSM
Do a sanity check whether provided file-to-be-pinned is actually a BPF
object (prog, map, btf) before calling security_path_mknod LSM hook. If
it's not, LSM hook doesn't have to be triggered, as the operation has no
chance of succeeding anyways.

Suggested-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/bpf/20230522232917.2454595-2-andrii@kernel.org
2023-05-23 16:56:37 +02:00
Anton Protopopov
b34ffb0c6d bpf: fix a memory leak in the LRU and LRU_PERCPU hash maps
The LRU and LRU_PERCPU maps allocate a new element on update before locking the
target hash table bucket. Right after that the maps try to lock the bucket.
If this fails, then maps return -EBUSY to the caller without releasing the
allocated element. This makes the element untracked: it doesn't belong to
either of free lists, and it doesn't belong to the hash table, so can't be
re-used; this eventually leads to the permanent -ENOMEM on LRU map updates,
which is unexpected. Fix this by returning the element to the local free list
if bucket locking fails.

Fixes: 20b6cc34ea ("bpf: Avoid hashtab deadlock with map_locked")
Signed-off-by: Anton Protopopov <aspsk@isovalent.com>
Link: https://lore.kernel.org/r/20230522154558.2166815-1-aspsk@isovalent.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-22 10:26:39 -07:00
Aditi Ghag
e924e80ee6 bpf: Add kfunc filter function to 'struct btf_kfunc_id_set'
This commit adds the ability to filter kfuncs to certain BPF program
types. This is required to limit bpf_sock_destroy kfunc implemented in
follow-up commits to programs with attach type 'BPF_TRACE_ITER'.

The commit adds a callback filter to 'struct btf_kfunc_id_set'.  The
filter has access to the `bpf_prog` construct including its properties
such as `expected_attached_type`.

Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com>
Link: https://lore.kernel.org/r/20230519225157.760788-7-aditi.ghag@isovalent.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-19 22:44:14 -07:00
Yafang Shao
e859e42951 bpf: Show target_{obj,btf}_id in tracing link fdinfo
The target_btf_id can help us understand which kernel function is
linked by a tracing prog. The target_btf_id and target_obj_id have
already been exposed to userspace, so we just need to show them.

The result as follows,

$ cat /proc/10673/fdinfo/10
pos:    0
flags:  02000000
mnt_id: 15
ino:    2094
link_type:      tracing
link_id:        2
prog_tag:       a04f5eef06a7f555
prog_id:        13
attach_type:    24
target_obj_id:  1
target_btf_id:  13964

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230517103126.68372-2-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-19 10:06:44 -07:00
Will Deacon
0613d8ca9a bpf: Fix mask generation for 32-bit narrow loads of 64-bit fields
A narrow load from a 64-bit context field results in a 64-bit load
followed potentially by a 64-bit right-shift and then a bitwise AND
operation to extract the relevant data.

In the case of a 32-bit access, an immediate mask of 0xffffffff is used
to construct a 64-bit BPP_AND operation which then sign-extends the mask
value and effectively acts as a glorified no-op. For example:

0:	61 10 00 00 00 00 00 00	r0 = *(u32 *)(r1 + 0)

results in the following code generation for a 64-bit field:

	ldr	x7, [x7]	// 64-bit load
	mov	x10, #0xffffffffffffffff
	and	x7, x7, x10

Fix the mask generation so that narrow loads always perform a 32-bit AND
operation:

	ldr	x7, [x7]	// 64-bit load
	mov	w10, #0xffffffff
	and	w7, w7, w10

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Krzesimir Nowak <krzesimir@kinvolk.io>
Cc: Andrey Ignatov <rdna@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Fixes: 31fd85816d ("bpf: permits narrower load from bpf program context fields")
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230518102528.1341-1-will@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-19 09:58:37 -07:00
Andrii Nakryiko
cff36398bd bpf: drop unnecessary user-triggerable WARN_ONCE in verifierl log
It's trivial for user to trigger "verifier log line truncated" warning,
as verifier has a fixed-sized buffer of 1024 bytes (as of now), and there are at
least two pieces of user-provided information that can be output through
this buffer, and both can be arbitrarily sized by user:
  - BTF names;
  - BTF.ext source code lines strings.

Verifier log buffer should be properly sized for typical verifier state
output. But it's sort-of expected that this buffer won't be long enough
in some circumstances. So let's drop the check. In any case code will
work correctly, at worst truncating a part of a single line output.

Reported-by: syzbot+8b2a08dfbd25fd933d75@syzkaller.appspotmail.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230516180409.3549088-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-16 22:34:50 -07:00
Jakub Kicinski
a0e35a648f bpf-next-for-netdev
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZGKqEAAKCRDbK58LschI
 g6LYAQDp1jAszCOkmJ8VUA0ZyC5NAFDv+7y9Nd1toYWYX1btzAEAkf8+5qBJ1qmI
 P5M0hjMTbH4MID9Aql10ZbMHheyOBAo=
 =NUQM
 -----END PGP SIGNATURE-----

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-05-16

We've added 57 non-merge commits during the last 19 day(s) which contain
a total of 63 files changed, 3293 insertions(+), 690 deletions(-).

The main changes are:

1) Add precision propagation to verifier for subprogs and callbacks,
   from Andrii Nakryiko.

2) Improve BPF's {g,s}setsockopt() handling with wrong option lengths,
   from Stanislav Fomichev.

3) Utilize pahole v1.25 for the kernel's BTF generation to filter out
   inconsistent function prototypes, from Alan Maguire.

4) Various dyn-pointer verifier improvements to relax restrictions,
   from Daniel Rosenberg.

5) Add a new bpf_task_under_cgroup() kfunc for designated task,
   from Feng Zhou.

6) Unblock tests for arm64 BPF CI after ftrace supporting direct call,
   from Florent Revest.

7) Add XDP hint kfunc metadata for RX hash/timestamp for igc,
   from Jesper Dangaard Brouer.

8) Add several new dyn-pointer kfuncs to ease their usability,
   from Joanne Koong.

9) Add in-depth LRU internals description and dot function graph,
   from Joe Stringer.

10) Fix KCSAN report on bpf_lru_list when accessing node->ref,
    from Martin KaFai Lau.

11) Only dump unprivileged_bpf_disabled log warning upon write,
    from Kui-Feng Lee.

12) Extend test_progs to directly passing allow/denylist file,
    from Stephen Veiss.

13) Fix BPF trampoline memleak upon failure attaching to fentry,
    from Yafang Shao.

14) Fix emitting struct bpf_tcp_sock type in vmlinux BTF,
    from Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (57 commits)
  bpf: Fix memleak due to fentry attach failure
  bpf: Remove bpf trampoline selector
  bpf, arm64: Support struct arguments in the BPF trampoline
  bpftool: JIT limited misreported as negative value on aarch64
  bpf: fix calculation of subseq_idx during precision backtracking
  bpf: Remove anonymous union in bpf_kfunc_call_arg_meta
  bpf: Document EFAULT changes for sockopt
  selftests/bpf: Correctly handle optlen > 4096
  selftests/bpf: Update EFAULT {g,s}etsockopt selftests
  bpf: Don't EFAULT for {g,s}setsockopt with wrong optlen
  libbpf: fix offsetof() and container_of() to work with CO-RE
  bpf: Address KCSAN report on bpf_lru_list
  bpf: Add --skip_encoding_btf_inconsistent_proto, --btf_gen_optimized to pahole flags for v1.25
  selftests/bpf: Accept mem from dynptr in helper funcs
  bpf: verifier: Accept dynptr mem as mem in helpers
  selftests/bpf: Check overflow in optional buffer
  selftests/bpf: Test allowing NULL buffer in dynptr slice
  bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)
  selftests/bpf: Add testcase for bpf_task_under_cgroup
  bpf: Add bpf_task_under_cgroup() kfunc
  ...
====================

Link: https://lore.kernel.org/r/20230515225603.27027-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-16 19:50:05 -07:00
Yafang Shao
108598c39e bpf: Fix memleak due to fentry attach failure
If it fails to attach fentry, the allocated bpf trampoline image will be
left in the system. That can be verified by checking /proc/kallsyms.

This meamleak can be verified by a simple bpf program as follows:

  SEC("fentry/trap_init")
  int fentry_run()
  {
      return 0;
  }

It will fail to attach trap_init because this function is freed after
kernel init, and then we can find the trampoline image is left in the
system by checking /proc/kallsyms.

  $ tail /proc/kallsyms
  ffffffffc0613000 t bpf_trampoline_6442453466_1  [bpf]
  ffffffffc06c3000 t bpf_trampoline_6442453466_1  [bpf]

  $ bpftool btf dump file /sys/kernel/btf/vmlinux | grep "FUNC 'trap_init'"
  [2522] FUNC 'trap_init' type_id=119 linkage=static

  $ echo $((6442453466 & 0x7fffffff))
  2522

Note that there are two left bpf trampoline images, that is because the
libbpf will fallback to raw tracepoint if -EINVAL is returned.

Fixes: e21aa34178 ("bpf: Fix fexit trampoline.")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Link: https://lore.kernel.org/bpf/20230515130849.57502-2-laoar.shao@gmail.com
2023-05-15 23:41:59 +02:00
Yafang Shao
47e79cbeea bpf: Remove bpf trampoline selector
After commit e21aa34178 ("bpf: Fix fexit trampoline."), the selector is only
used to indicate how many times the bpf trampoline image are updated and been
displayed in the trampoline ksym name. After the trampoline is freed, the
selector will start from 0 again. So the selector is a useless value to the
user. We can remove it.

If the user want to check whether the bpf trampoline image has been updated
or not, the user can compare the address. Each time the trampoline image is
updated, the address will change consequently. Jiri also pointed out another
issue that perf is still using the old name "bpf_trampoline_%lu", so this
change can fix the issue in perf.

Fixes: e21aa34178 ("bpf: Fix fexit trampoline.")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Link: https://lore.kernel.org/bpf/ZFvOOlrmHiY9AgXE@krava
Link: https://lore.kernel.org/bpf/20230515130849.57502-3-laoar.shao@gmail.com
2023-05-15 22:18:19 +02:00
Andrii Nakryiko
d84b1a6708 bpf: fix calculation of subseq_idx during precision backtracking
Subsequent instruction index (subseq_idx) is an index of an instruction
that was verified/executed by verifier after the currently processed
instruction. It is maintained during precision backtracking processing
and is used to detect various subprog calling conditions.

This patch fixes the bug with incorrectly resetting subseq_idx to -1
when going from child state to parent state during backtracking. If we
don't maintain correct subseq_idx we can misidentify subprog calls
leading to precision tracking bugs.

One such case was triggered by test_global_funcs/global_func9 test where
global subprog call happened to be the very last instruction in parent
state, leading to subseq_idx==-1, triggering WARN_ONCE:

  [   36.045754] verifier backtracking bug
  [   36.045764] WARNING: CPU: 13 PID: 2073 at kernel/bpf/verifier.c:3503 __mark_chain_precision+0xcc6/0xde0
  [   36.046819] Modules linked in: aesni_intel(E) crypto_simd(E) cryptd(E) kvm_intel(E) kvm(E) irqbypass(E) i2c_piix4(E) serio_raw(E) i2c_core(E) crc32c_intel)
  [   36.048040] CPU: 13 PID: 2073 Comm: test_progs Tainted: G        W  OE      6.3.0-07976-g4d585f48ee6b-dirty #972
  [   36.048783] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
  [   36.049648] RIP: 0010:__mark_chain_precision+0xcc6/0xde0
  [   36.050038] Code: 3d 82 c6 05 bb 35 32 02 01 e8 66 21 ec ff 0f 0b b8 f2 ff ff ff e9 30 f5 ff ff 48 c7 c7 f3 61 3d 82 4c 89 0c 24 e8 4a 21 ec ff <0f> 0b 4c0

With the fix precision tracking across multiple states works correctly now:

mark_precise: frame0: last_idx 45 first_idx 38 subseq_idx -1
mark_precise: frame0: regs=r8 stack= before 44: (61) r7 = *(u32 *)(r10 -4)
mark_precise: frame0: regs=r8 stack= before 43: (85) call pc+41
mark_precise: frame0: regs=r8 stack= before 42: (07) r1 += -48
mark_precise: frame0: regs=r8 stack= before 41: (bf) r1 = r10
mark_precise: frame0: regs=r8 stack= before 40: (63) *(u32 *)(r10 -48) = r1
mark_precise: frame0: regs=r8 stack= before 39: (b4) w1 = 0
mark_precise: frame0: regs=r8 stack= before 38: (85) call pc+38
mark_precise: frame0: parent state regs=r8 stack=:  R0_w=scalar() R1_w=map_value(off=4,ks=4,vs=8,imm=0) R6=1 R7_w=scalar() R8_r=P0 R10=fpm
mark_precise: frame0: last_idx 36 first_idx 28 subseq_idx 38
mark_precise: frame0: regs=r8 stack= before 36: (18) r1 = 0xffff888104f2ed14
mark_precise: frame0: regs=r8 stack= before 35: (85) call pc+33
mark_precise: frame0: regs=r8 stack= before 33: (18) r1 = 0xffff888104f2ed10
mark_precise: frame0: regs=r8 stack= before 32: (85) call pc+36
mark_precise: frame0: regs=r8 stack= before 31: (07) r1 += -4
mark_precise: frame0: regs=r8 stack= before 30: (bf) r1 = r10
mark_precise: frame0: regs=r8 stack= before 29: (63) *(u32 *)(r10 -4) = r7
mark_precise: frame0: regs=r8 stack= before 28: (4c) w7 |= w0
mark_precise: frame0: parent state regs=r8 stack=:  R0_rw=scalar() R6=1 R7_rw=scalar() R8_rw=P0 R10=fp0 fp-48_r=mmmmmmmm
mark_precise: frame0: last_idx 27 first_idx 16 subseq_idx 28
mark_precise: frame0: regs=r8 stack= before 27: (85) call pc+31
mark_precise: frame0: regs=r8 stack= before 26: (b7) r1 = 0
mark_precise: frame0: regs=r8 stack= before 25: (b7) r8 = 0

Note how subseq_idx starts out as -1, then is preserved as 38 and then 28 as we
go up the parent state chain.

Reported-by: Alexei Starovoitov <ast@kernel.org>
Fixes: fde2a3882b ("bpf: support precision propagation in the presence of subprogs")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230515180710.1535018-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-15 12:06:31 -07:00
Dave Marchevsky
4d585f48ee bpf: Remove anonymous union in bpf_kfunc_call_arg_meta
For kfuncs like bpf_obj_drop and bpf_refcount_acquire - which take
user-defined types as input - the verifier needs to track the specific
type passed in when checking a particular kfunc call. This requires
tracking (btf, btf_id) tuple. In commit 7c50b1cb76
("bpf: Add bpf_refcount_acquire kfunc") I added an anonymous union with
inner structs named after the specific kfuncs tracking this information,
with the goal of making it more obvious which kfunc this data was being
tracked / expected to be tracked on behalf of.

In a recent series adding a new user of this tuple, Alexei mentioned
that he didn't like this union usage as it doesn't really help with
readability or bug-proofing ([0]). In an offline convo we agreed to
have the tuple be fields (arg_btf, arg_btf_id), with comments in
bpf_kfunc_call_arg_meta definition enumerating the uses of the fields by
kfunc-specific handling logic. Such a pattern is used by struct
bpf_reg_state without trouble.

Accordingly, this patch removes the anonymous union in favor of arg_btf
and arg_btf_id fields and comment enumerating their current uses. The
patch also removes struct btf_and_id, which was only being used by the
removed union's inner structs.

This is a mechanical change, existing linked_list and rbtree tests will
validate that correct (btf, btf_id) are being passed.

  [0]: https://lore.kernel.org/bpf/20230505021707.vlyiwy57vwxglbka@dhcp-172-26-102-232.dhcp.thefacebook.com

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230510213047.1633612-1-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-15 07:17:12 -07:00
Jakub Kicinski
e1505c1cc8 bpf: netdev: init the offload table earlier
Some netdevices may get unregistered before late_initcall(),
we have to move the hashtable init earlier.

Fixes: f1fc43d039 ("bpf: Move offload initialization into late_initcall")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217399
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230505215836.491485-1-kuba@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-15 07:07:41 -07:00
Stanislav Fomichev
29ebbba7d4 bpf: Don't EFAULT for {g,s}setsockopt with wrong optlen
With the way the hooks implemented right now, we have a special
condition: optval larger than PAGE_SIZE will expose only first 4k into
BPF; any modifications to the optval are ignored. If the BPF program
doesn't handle this condition by resetting optlen to 0,
the userspace will get EFAULT.

The intention of the EFAULT was to make it apparent to the
developers that the program is doing something wrong.
However, this inadvertently might affect production workloads
with the BPF programs that are not too careful (i.e., returning EFAULT
for perfectly valid setsockopt/getsockopt calls).

Let's try to minimize the chance of BPF program screwing up userspace
by ignoring the output of those BPF programs (instead of returning
EFAULT to the userspace). pr_info_once those cases to
the dmesg to help with figuring out what's going wrong.

Fixes: 0d01da6afc ("bpf: implement getsockopt and setsockopt hooks")
Suggested-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230511170456.1759459-2-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-13 16:20:15 -07:00
Martin KaFai Lau
ee9fd0ac30 bpf: Address KCSAN report on bpf_lru_list
KCSAN reported a data-race when accessing node->ref.
Although node->ref does not have to be accurate,
take this chance to use a more common READ_ONCE() and WRITE_ONCE()
pattern instead of data_race().

There is an existing bpf_lru_node_is_ref() and bpf_lru_node_set_ref().
This patch also adds bpf_lru_node_clear_ref() to do the
WRITE_ONCE(node->ref, 0) also.

==================================================================
BUG: KCSAN: data-race in __bpf_lru_list_rotate / __htab_lru_percpu_map_update_elem

write to 0xffff888137038deb of 1 bytes by task 11240 on cpu 1:
__bpf_lru_node_move kernel/bpf/bpf_lru_list.c:113 [inline]
__bpf_lru_list_rotate_active kernel/bpf/bpf_lru_list.c:149 [inline]
__bpf_lru_list_rotate+0x1bf/0x750 kernel/bpf/bpf_lru_list.c:240
bpf_lru_list_pop_free_to_local kernel/bpf/bpf_lru_list.c:329 [inline]
bpf_common_lru_pop_free kernel/bpf/bpf_lru_list.c:447 [inline]
bpf_lru_pop_free+0x638/0xe20 kernel/bpf/bpf_lru_list.c:499
prealloc_lru_pop kernel/bpf/hashtab.c:290 [inline]
__htab_lru_percpu_map_update_elem+0xe7/0x820 kernel/bpf/hashtab.c:1316
bpf_percpu_hash_update+0x5e/0x90 kernel/bpf/hashtab.c:2313
bpf_map_update_value+0x2a9/0x370 kernel/bpf/syscall.c:200
generic_map_update_batch+0x3ae/0x4f0 kernel/bpf/syscall.c:1687
bpf_map_do_batch+0x2d9/0x3d0 kernel/bpf/syscall.c:4534
__sys_bpf+0x338/0x810
__do_sys_bpf kernel/bpf/syscall.c:5096 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5094 [inline]
__x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5094
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888137038deb of 1 bytes by task 11241 on cpu 0:
bpf_lru_node_set_ref kernel/bpf/bpf_lru_list.h:70 [inline]
__htab_lru_percpu_map_update_elem+0x2f1/0x820 kernel/bpf/hashtab.c:1332
bpf_percpu_hash_update+0x5e/0x90 kernel/bpf/hashtab.c:2313
bpf_map_update_value+0x2a9/0x370 kernel/bpf/syscall.c:200
generic_map_update_batch+0x3ae/0x4f0 kernel/bpf/syscall.c:1687
bpf_map_do_batch+0x2d9/0x3d0 kernel/bpf/syscall.c:4534
__sys_bpf+0x338/0x810
__do_sys_bpf kernel/bpf/syscall.c:5096 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5094 [inline]
__x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5094
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11241 Comm: syz-executor.3 Not tainted 6.3.0-rc7-syzkaller-00136-g6a66fdd29ea1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
==================================================================

Reported-by: syzbot+ebe648a84e8784763f82@syzkaller.appspotmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230511043748.1384166-1-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-12 12:01:03 -07:00
Daniel Rosenberg
2012c867c8 bpf: verifier: Accept dynptr mem as mem in helpers
This allows using memory retrieved from dynptrs with helper functions
that accept ARG_PTR_TO_MEM. For instance, results from bpf_dynptr_data
can be passed along to bpf_strncmp.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20230506013134.2492210-5-drosen@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-06 16:42:57 -07:00
Daniel Rosenberg
3bda08b636 bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)
bpf_dynptr_slice(_rw) uses a user provided buffer if it can not provide
a pointer to a block of contiguous memory. This buffer is unused in the
case of local dynptrs, and may be unused in other cases as well. There
is no need to require the buffer, as the kfunc can just return NULL if
it was needed and not provided.

This adds another kfunc annotation, __opt, which combines with __sz and
__szk to allow the buffer associated with the size to be NULL. If the
buffer is NULL, the verifier does not check that the buffer is of
sufficient size.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20230506013134.2492210-2-drosen@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-06 16:42:57 -07:00
Feng Zhou
b5ad4cdc46 bpf: Add bpf_task_under_cgroup() kfunc
Add a kfunc that's similar to the bpf_current_task_under_cgroup.
The difference is that it is a designated task.

When hook sched related functions, sometimes it is necessary to
specify a task instead of the current task.

Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230506031545.35991-2-zhoufeng.zf@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-06 13:56:38 -07:00
Andrii Nakryiko
fde2a3882b bpf: support precision propagation in the presence of subprogs
Add support precision backtracking in the presence of subprogram frames in
jump history.

This means supporting a few different kinds of subprogram invocation
situations, all requiring a slightly different handling in precision
backtracking handling logic:
  - static subprogram calls;
  - global subprogram calls;
  - callback-calling helpers/kfuncs.

For each of those we need to handle a few precision propagation cases:
  - what to do with precision of subprog returns (r0);
  - what to do with precision of input arguments;
  - for all of them callee-saved registers in caller function should be
    propagated ignoring subprog/callback part of jump history.

N.B. Async callback-calling helpers (currently only
bpf_timer_set_callback()) are transparent to all this because they set
a separate async callback environment and thus callback's history is not
shared with main program's history. So as far as all the changes in this
commit goes, such helper is just a regular helper.

Let's look at all these situation in more details. Let's start with
static subprogram being called, using an exxerpt of a simple main
program and its static subprog, indenting subprog's frame slightly to
make everything clear.

frame 0				frame 1			precision set
=======				=======			=============

 9: r6 = 456;
10: r1 = 123;						fr0: r6
11: call pc+10;						fr0: r1, r6
				22: r0 = r1;		fr0: r6;     fr1: r1
				23: exit		fr0: r6;     fr1: r0
12: r1 = <map_pointer>					fr0: r0, r6
13: r1 += r0;						fr0: r0, r6
14: r1 += r6;						fr0: r6
15: exit

As can be seen above main function is passing 123 as single argument to
an identity (`return x;`) subprog. Returned value is used to adjust map
pointer offset, which forces r0 to be marked as precise. Then
instruction #14 does the same for callee-saved r6, which will have to be
backtracked all the way to instruction #9. For brevity, precision sets
for instruction #13 and #14 are combined in the diagram above.

First, for subprog calls, r0 returned from subprog (in frame 0) has to
go into subprog's frame 1, and should be cleared from frame 0. So we go
back into subprog's frame knowing we need to mark r0 precise. We then
see that insn #22 sets r0 from r1, so now we care about marking r1
precise.  When we pop up from subprog's frame back into caller at
insn #11 we keep r1, as it's an argument-passing register, so we eventually
find `10: r1 = 123;` and satify precision propagation chain for insn #13.

This example demonstrates two sets of rules:
  - r0 returned after subprog call has to be moved into subprog's r0 set;
  - *static* subprog arguments (r1-r5) are moved back to caller precision set.

Let's look at what happens with callee-saved precision propagation. Insn #14
mark r6 as precise. When we get into subprog's frame, we keep r6 in
frame 0's precision set *only*. Subprog itself has its own set of
independent r6-r10 registers and is not affected. When we eventually
made our way out of subprog frame we keep r6 in precision set until we
reach `9: r6 = 456;`, satisfying propagation. r6-r10 propagation is
perhaps the simplest aspect, it always stays in its original frame.

That's pretty much all we have to do to support precision propagation
across *static subprog* invocation.

Let's look at what happens when we have global subprog invocation.

frame 0				frame 1			precision set
=======				=======			=============

 9: r6 = 456;
10: r1 = 123;						fr0: r6
11: call pc+10; # global subprog			fr0: r6
12: r1 = <map_pointer>					fr0: r0, r6
13: r1 += r0;						fr0: r0, r6
14: r1 += r6;						fr0: r6;
15: exit

Starting from insn #13, r0 has to be precise. We backtrack all the way
to insn #11 (call pc+10) and see that subprog is global, so was already
validated in isolation. As opposed to static subprog, global subprog
always returns unknown scalar r0, so that satisfies precision
propagation and we drop r0 from precision set. We are done for insns #13.

Now for insn #14. r6 is in precision set, we backtrack to `call pc+10;`.
Here we need to recognize that this is effectively both exit and entry
to global subprog, which means we stay in caller's frame. So we carry on
with r6 still in precision set, until we satisfy it at insn #9. The only
hard part with global subprogs is just knowing when it's a global func.

Lastly, callback-calling helpers and kfuncs do simulate subprog calls,
so jump history will have subprog instructions in between caller
program's instructions, but the rules of propagating r0 and r1-r5
differ, because we don't actually directly call callback. We actually
call helper/kfunc, which at runtime will call subprog, so the only
difference between normal helper/kfunc handling is that we need to make
sure to skip callback simulatinog part of jump history.
Let's look at an example to make this clearer.

frame 0				frame 1			precision set
=======				=======			=============

 8: r6 = 456;
 9: r1 = 123;						fr0: r6
10: r2 = &callback;					fr0: r6
11: call bpf_loop;					fr0: r6
				22: r0 = r1;		fr0: r6      fr1:
				23: exit		fr0: r6      fr1:
12: r1 = <map_pointer>					fr0: r0, r6
13: r1 += r0;						fr0: r0, r6
14: r1 += r6;						fr0: r6;
15: exit

Again, insn #13 forces r0 to be precise. As soon as we get to `23: exit`
we see that this isn't actually a static subprog call (it's `call
bpf_loop;` helper call instead). So we clear r0 from precision set.

For callee-saved register, there is no difference: it stays in frame 0's
precision set, we go through insn #22 and #23, ignoring them until we
get back to caller frame 0, eventually satisfying precision backtrack
logic at insn #8 (`r6 = 456;`).

Assuming callback needed to set r0 as precise at insn #23, we'd
backtrack to insn #22, switching from r0 to r1, and then at the point
when we pop back to frame 0 at insn #11, we'll clear r1-r5 from
precision set, as we don't really do a subprog call directly, so there
is no input argument precision propagation.

That's pretty much it. With these changes, it seems like the only still
unsupported situation for precision backpropagation is the case when
program is accessing stack through registers other than r10. This is
still left as unsupported (though rare) case for now.

As for results. For selftests, few positive changes for bigger programs,
cls_redirect in dynptr variant benefitting the most:

[vmuser@archvm bpf]$ ./veristat -C ~/subprog-precise-before-results.csv ~/subprog-precise-after-results.csv -f @veristat.cfg -e file,prog,insns -f 'insns_diff!=0'
File                                      Program        Insns (A)  Insns (B)  Insns     (DIFF)
----------------------------------------  -------------  ---------  ---------  ----------------
pyperf600_bpf_loop.bpf.linked1.o          on_event            2060       2002      -58 (-2.82%)
test_cls_redirect_dynptr.bpf.linked1.o    cls_redirect       15660       2914  -12746 (-81.39%)
test_cls_redirect_subprogs.bpf.linked1.o  cls_redirect       61620      59088    -2532 (-4.11%)
xdp_synproxy_kern.bpf.linked1.o           syncookie_tc      109980      86278  -23702 (-21.55%)
xdp_synproxy_kern.bpf.linked1.o           syncookie_xdp      97716      85147  -12569 (-12.86%)

Cilium progress don't really regress. They don't use subprogs and are
mostly unaffected, but some other fixes and improvements could have
changed something. This doesn't appear to be the case:

[vmuser@archvm bpf]$ ./veristat -C ~/subprog-precise-before-results-cilium.csv ~/subprog-precise-after-results-cilium.csv -e file,prog,insns -f 'insns_diff!=0'
File           Program                         Insns (A)  Insns (B)  Insns (DIFF)
-------------  ------------------------------  ---------  ---------  ------------
bpf_host.o     tail_nodeport_nat_ingress_ipv6       4983       5003  +20 (+0.40%)
bpf_lxc.o      tail_nodeport_nat_ingress_ipv6       4983       5003  +20 (+0.40%)
bpf_overlay.o  tail_nodeport_nat_ingress_ipv6       4983       5003  +20 (+0.40%)
bpf_xdp.o      tail_handle_nat_fwd_ipv6            12475      12504  +29 (+0.23%)
bpf_xdp.o      tail_nodeport_nat_ingress_ipv6       6363       6371   +8 (+0.13%)

Looking at (somewhat anonymized) Meta production programs, we see mostly
insignificant variation in number of instructions, with one program
(syar_bind6_protect6) benefitting the most at -17%.

[vmuser@archvm bpf]$ ./veristat -C ~/subprog-precise-before-results-fbcode.csv ~/subprog-precise-after-results-fbcode.csv -e prog,insns -f 'insns_diff!=0'
Program                   Insns (A)  Insns (B)  Insns     (DIFF)
------------------------  ---------  ---------  ----------------
on_request_context_event        597        585      -12 (-2.01%)
read_async_py_stack           43789      43657     -132 (-0.30%)
read_sync_py_stack            35041      37599    +2558 (+7.30%)
rrm_usdt                        946        940       -6 (-0.63%)
sysarmor_inet6_bind           28863      28249     -614 (-2.13%)
sysarmor_inet_bind            28845      28240     -605 (-2.10%)
syar_bind4_protect4          154145     147640    -6505 (-4.22%)
syar_bind6_protect6          165242     137088  -28154 (-17.04%)
syar_task_exit_setgid         21289      19720    -1569 (-7.37%)
syar_task_exit_setuid         21290      19721    -1569 (-7.37%)
do_uprobe                     19967      19413     -554 (-2.77%)
tw_twfw_ingress              215877     204833   -11044 (-5.12%)
tw_twfw_tc_in                215877     204833   -11044 (-5.12%)

But checking duration (wall clock) differences, that is the actual time taken
by verifier to validate programs, we see a sometimes dramatic improvements, all
the way to about 16x improvements:

[vmuser@archvm bpf]$ ./veristat -C ~/subprog-precise-before-results-meta.csv ~/subprog-precise-after-results-meta.csv -e prog,duration -s duration_diff^ | head -n20
Program                                   Duration (us) (A)  Duration (us) (B)  Duration (us) (DIFF)
----------------------------------------  -----------------  -----------------  --------------------
tw_twfw_ingress                                     4488374             272836    -4215538 (-93.92%)
tw_twfw_tc_in                                       4339111             268175    -4070936 (-93.82%)
tw_twfw_egress                                      3521816             270751    -3251065 (-92.31%)
tw_twfw_tc_eg                                       3472878             284294    -3188584 (-91.81%)
balancer_ingress                                     343119             291391      -51728 (-15.08%)
syar_bind6_protect6                                   78992              64782      -14210 (-17.99%)
ttls_tc_ingress                                       11739               8176       -3563 (-30.35%)
kprobe__security_inode_link                           13864              11341       -2523 (-18.20%)
read_sync_py_stack                                    21927              19442       -2485 (-11.33%)
read_async_py_stack                                   30444              28136        -2308 (-7.58%)
syar_task_exit_setuid                                 10256               8440       -1816 (-17.71%)

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-9-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:35 -07:00
Andrii Nakryiko
c50c0b57a5 bpf: fix mark_all_scalars_precise use in mark_chain_precision
When precision backtracking bails out due to some unsupported sequence
of instructions (e.g., stack access through register other than r10), we
need to mark all SCALAR registers as precise to be safe. Currently,
though, we mark SCALARs precise only starting from the state we detected
unsupported condition, which could be one of the parent states of the
actual current state. This will leave some registers potentially not
marked as precise, even though they should. So make sure we start
marking scalars as precise from current state (env->cur_state).

Further, we don't currently detect a situation when we end up with some
stack slots marked as needing precision, but we ran out of available
states to find the instructions that populate those stack slots. This is
akin the `i >= func->allocated_stack / BPF_REG_SIZE` check and should be
handled similarly by falling back to marking all SCALARs precise. Add
this check when we run out of states.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:35 -07:00
Andrii Nakryiko
f655badf2a bpf: fix propagate_precision() logic for inner frames
Fix propagate_precision() logic to perform propagation of all necessary
registers and stack slots across all active frames *in one batch step*.

Doing this for each register/slot in each individual frame is wasteful,
but the main problem is that backtracking of instruction in any frame
except the deepest one just doesn't work. This is due to backtracking
logic relying on jump history, and available jump history always starts
(or ends, depending how you view it) in current frame. So, if
prog A (frame #0) called subprog B (frame #1) and we need to propagate
precision of, say, register R6 (callee-saved) within frame #0, we
actually don't even know where jump history that corresponds to prog
A even starts. We'd need to skip subprog part of jump history first to
be able to do this.

Luckily, with struct backtrack_state and __mark_chain_precision()
handling bitmasks tracking/propagation across all active frames at the
same time (added in previous patch), propagate_precision() can be both
fixed and sped up by setting all the necessary bits across all frames
and then performing one __mark_chain_precision() pass. This makes it
unnecessary to skip subprog parts of jump history.

We also improve logging along the way, to clearly specify which
registers' and slots' precision markings are propagated within which
frame. Each frame will have dedicated line and all registers and stack
slots from that frame will be reported in format similar to precision
backtrack regs/stack logging. E.g.:

frame 1: propagating r1,r2,r3,fp-8,fp-16
frame 0: propagating r3,r9,fp-120

Fixes: 529409ea92 ("bpf: propagate precision across all frames, not just the last one")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:35 -07:00
Andrii Nakryiko
1ef22b6865 bpf: maintain bitmasks across all active frames in __mark_chain_precision
Teach __mark_chain_precision logic to maintain register/stack masks
across all active frames when going from child state to parent state.
Currently this should be mostly no-op, as precision backtracking usually
bails out when encountering subprog entry/exit.

It's not very apparent from the diff due to increased indentation, but
the logic remains the same, except everything is done on specific `fr`
frame index. Calls to bt_clear_reg() and bt_clear_slot() are replaced
with frame-specific bt_clear_frame_reg() and bt_clear_frame_slot(),
where frame index is passed explicitly, instead of using current frame
number.

We also adjust logging to emit affected frame number. And we also add
better logging of human-readable register and stack slot masks, similar
to previous patch.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:35 -07:00
Andrii Nakryiko
d9439c21a9 bpf: improve precision backtrack logging
Add helper to format register and stack masks in more human-readable
format. Adjust logging a bit during backtrack propagation and especially
during forcing precision fallback logic to make it clearer what's going
on (with log_level=2, of course), and also start reporting affected
frame depth. This is in preparation for having more than one active
frame later when precision propagation between subprog calls is added.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:35 -07:00
Andrii Nakryiko
407958a0e9 bpf: encapsulate precision backtracking bookkeeping
Add struct backtrack_state and straightforward API around it to keep
track of register and stack masks used and maintained during precision
backtracking process. Having this logic separately allow to keep
high-level backtracking algorithm cleaner, but also it sets us up to
cleanly keep track of register and stack masks per frame, allowing (with
some further logic adjustments) to perform precision backpropagation
across multiple frames (i.e., subprog calls).

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:35 -07:00
Andrii Nakryiko
e0bf462276 bpf: mark relevant stack slots scratched for register read instructions
When handling instructions that read register slots, mark relevant stack
slots as scratched so that verifier log would contain those slots' states, in
addition to currently emitted registers with stack slot offsets.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-04 22:35:34 -07:00
Kui-Feng Lee
fedf99200a bpf: Print a warning only if writing to unprivileged_bpf_disabled.
Only print the warning message if you are writing to
"/proc/sys/kernel/unprivileged_bpf_disabled".

The kernel may print an annoying warning when you read
"/proc/sys/kernel/unprivileged_bpf_disabled" saying

  WARNING: Unprivileged eBPF is enabled with eIBRS on, data leaks possible
  via Spectre v2 BHB attacks!

However, this message is only meaningful when the feature is
disabled or enabled.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230502181418.308479-1-kuifeng@meta.com
2023-05-02 16:20:31 -07:00
Linus Torvalds
86e98ed15b cgroup changes for v6.4-rc1
* cpuset changes including the fix for an incorrect interaction with CPU
   hotplug and an optimization.
 
 * Other doc and cosmetic changes.
 -----BEGIN PGP SIGNATURE-----
 
 iIQEABYIACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCZErfng4cdGpAa2VybmVs
 Lm9yZwAKCRCxYfJx3gVYGVVtAQCDycK4VSgc4nsFPG1vh1Oy1A723ciEUwAbKmV/
 F1n7xwEA68FiDvE29LpMJJuYP9HnX0A5zRMyNnb52kN9jmgcEQI=
 =ALol
 -----END PGP SIGNATURE-----

Merge tag 'cgroup-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - cpuset changes including the fix for an incorrect interaction with
   CPU hotplug and an optimization

 - Other doc and cosmetic changes

* tag 'cgroup-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs: cgroup-v1/cpusets: update libcgroup project link
  cgroup/cpuset: Minor updates to test_cpuset_prs.sh
  cgroup/cpuset: Include offline CPUs when tasks' cpumasks in top_cpuset are updated
  cgroup/cpuset: Skip task update if hotplug doesn't affect current cpuset
  cpuset: Clean up cpuset_node_allowed
  cgroup: bpf: use cgroup_lock()/cgroup_unlock() wrappers
2023-04-29 10:05:22 -07:00
Joanne Koong
361f129f3c bpf: Add bpf_dynptr_clone
The cloned dynptr will point to the same data as its parent dynptr,
with the same type, offset, size and read-only properties.

Any writes to a dynptr will be reflected across all instances
(by 'instance', this means any dynptrs that point to the same
underlying data).

Please note that data slice and dynptr invalidations will affect all
instances as well. For example, if bpf_dynptr_write() is called on an
skb-type dynptr, all data slices of dynptr instances to that skb
will be invalidated as well (eg data slices of any clones, parents,
grandparents, ...). Another example is if a ringbuf dynptr is submitted,
any instance of that dynptr will be invalidated.

Changing the view of the dynptr (eg advancing the offset or
trimming the size) will only affect that dynptr and not affect any
other instances.

One example use case where cloning may be helpful is for hashing or
iterating through dynptr data. Cloning will allow the user to maintain
the original view of the dynptr for future use, while also allowing
views to smaller subsets of the data after the offset is advanced or the
size is trimmed.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230420071414.570108-5-joannelkoong@gmail.com
2023-04-27 10:40:47 +02:00
Joanne Koong
26662d7347 bpf: Add bpf_dynptr_size
bpf_dynptr_size returns the number of usable bytes in a dynptr.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230420071414.570108-4-joannelkoong@gmail.com
2023-04-27 10:40:41 +02:00
Joanne Koong
540ccf96dd bpf: Add bpf_dynptr_is_null and bpf_dynptr_is_rdonly
bpf_dynptr_is_null returns true if the dynptr is null / invalid
(determined by whether ptr->data is NULL), else false if
the dynptr is a valid dynptr.

bpf_dynptr_is_rdonly returns true if the dynptr is read-only,
else false if the dynptr is read-writable. If the dynptr is
null / invalid, false is returned by default.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230420071414.570108-3-joannelkoong@gmail.com
2023-04-27 10:40:36 +02:00
Joanne Koong
987d0242d1 bpf: Add bpf_dynptr_adjust
Add a new kfunc

int bpf_dynptr_adjust(struct bpf_dynptr_kern *ptr, u32 start, u32 end);

which adjusts the dynptr to reflect the new [start, end) interval.
In particular, it advances the offset of the dynptr by "start" bytes,
and if end is less than the size of the dynptr, then this will trim the
dynptr accordingly.

Adjusting the dynptr interval may be useful in certain situations.
For example, when hashing which takes in generic dynptrs, if the dynptr
points to a struct but only a certain memory region inside the struct
should be hashed, adjust can be used to narrow in on the
specific region to hash.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230420071414.570108-2-joannelkoong@gmail.com
2023-04-27 10:40:31 +02:00
Linus Torvalds
6e98b09da9 Networking changes for 6.4.
Core
 ----
 
  - Introduce a config option to tweak MAX_SKB_FRAGS. Increasing the
    default value allows for better BIG TCP performances.
 
  - Reduce compound page head access for zero-copy data transfers.
 
  - RPS/RFS improvements, avoiding unneeded NET_RX_SOFTIRQ when possible.
 
  - Threaded NAPI improvements, adding defer skb free support and unneeded
    softirq avoidance.
 
  - Address dst_entry reference count scalability issues, via false
    sharing avoidance and optimize refcount tracking.
 
  - Add lockless accesses annotation to sk_err[_soft].
 
  - Optimize again the skb struct layout.
 
  - Extends the skb drop reasons to make it usable by multiple
    subsystems.
 
  - Better const qualifier awareness for socket casts.
 
 BPF
 ---
 
  - Add skb and XDP typed dynptrs which allow BPF programs for more
    ergonomic and less brittle iteration through data and variable-sized
    accesses.
 
  - Add a new BPF netfilter program type and minimal support to hook
    BPF programs to netfilter hooks such as prerouting or forward.
 
  - Add more precise memory usage reporting for all BPF map types.
 
  - Adds support for using {FOU,GUE} encap with an ipip device operating
    in collect_md mode and add a set of BPF kfuncs for controlling encap
    params.
 
  - Allow BPF programs to detect at load time whether a particular kfunc
    exists or not, and also add support for this in light skeleton.
 
  - Bigger batch of BPF verifier improvements to prepare for upcoming BPF
    open-coded iterators allowing for less restrictive looping capabilities.
 
  - Rework RCU enforcement in the verifier, add kptr_rcu and enforce BPF
    programs to NULL-check before passing such pointers into kfunc.
 
  - Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and in
    local storage maps.
 
  - Enable RCU semantics for task BPF kptrs and allow referenced kptr
    tasks to be stored in BPF maps.
 
  - Add support for refcounted local kptrs to the verifier for allowing
    shared ownership, useful for adding a node to both the BPF list and
    rbtree.
 
  - Add BPF verifier support for ST instructions in convert_ctx_access()
    which will help new -mcpu=v4 clang flag to start emitting them.
 
  - Add ARM32 USDT support to libbpf.
 
  - Improve bpftool's visual program dump which produces the control
    flow graph in a DOT format by adding C source inline annotations.
 
 Protocols
 ---------
 
  - IPv4: Allow adding to IPv4 address a 'protocol' tag. Such value
    indicates the provenance of the IP address.
 
  - IPv6: optimize route lookup, dropping unneeded R/W lock acquisition.
 
  - Add the handshake upcall mechanism, allowing the user-space
    to implement generic TLS handshake on kernel's behalf.
 
  - Bridge: support per-{Port, VLAN} neighbor suppression, increasing
    resilience to nodes failures.
 
  - SCTP: add support for Fair Capacity and Weighted Fair Queueing
    schedulers.
 
  - MPTCP: delay first subflow allocation up to its first usage. This
    will allow for later better LSM interaction.
 
  - xfrm: Remove inner/outer modes from input/output path. These are
    not needed anymore.
 
  - WiFi:
    - reduced neighbor report (RNR) handling for AP mode
    - HW timestamping support
    - support for randomized auth/deauth TA for PASN privacy
    - per-link debugfs for multi-link
    - TC offload support for mac80211 drivers
    - mac80211 mesh fast-xmit and fast-rx support
    - enable Wi-Fi 7 (EHT) mesh support
 
 Netfilter
 ---------
 
  - Add nf_tables 'brouting' support, to force a packet to be routed
    instead of being bridged.
 
  - Update bridge netfilter and ovs conntrack helpers to handle
    IPv6 Jumbo packets properly, i.e. fetch the packet length
    from hop-by-hop extension header. This is needed for BIT TCP
    support.
 
  - The iptables 32bit compat interface isn't compiled in by default
    anymore.
 
  - Move ip(6)tables builtin icmp matches to the udptcp one.
    This has the advantage that icmp/icmpv6 match doesn't load the
    iptables/ip6tables modules anymore when iptables-nft is used.
 
  - Extended netlink error report for netdevice in flowtables and
    netdev/chains. Allow for incrementally add/delete devices to netdev
    basechain. Allow to create netdev chain without device.
 
 Driver API
 ----------
 
  - Remove redundant Device Control Error Reporting Enable, as PCI core
    has already error reporting enabled at enumeration time.
 
  - Move Multicast DB netlink handlers to core, allowing devices other
    then bridge to use them.
 
  - Allow the page_pool to directly recycle the pages from safely
    localized NAPI.
 
  - Implement lockless TX queue stop/wake combo macros, allowing for
    further code de-duplication and sanitization.
 
  - Add YNL support for user headers and struct attrs.
 
  - Add partial YNL specification for devlink.
 
  - Add partial YNL specification for ethtool.
 
  - Add tc-mqprio and tc-taprio support for preemptible traffic classes.
 
  - Add tx push buf len param to ethtool, specifies the maximum number
    of bytes of a transmitted packet a driver can push directly to the
    underlying device.
 
  - Add basic LED support for switch/phy.
 
  - Add NAPI documentation, stop relaying on external links.
 
  - Convert dsa_master_ioctl() to netdev notifier. This is a preparatory
    work to make the hardware timestamping layer selectable by user
    space.
 
  - Add transceiver support and improve the error messages for CAN-FD
    controllers.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - AMD/Pensando core device support
    - MediaTek MT7981 SoC
    - MediaTek MT7988 SoC
    - Broadcom BCM53134 embedded switch
    - Texas Instruments CPSW9G ethernet switch
    - Qualcomm EMAC3 DWMAC ethernet
    - StarFive JH7110 SoC
    - NXP CBTX ethernet PHY
 
  - WiFi:
    - Apple M1 Pro/Max devices
    - RealTek rtl8710bu/rtl8188gu
    - RealTek rtl8822bs, rtl8822cs and rtl8821cs SDIO chipset
 
  - Bluetooth:
    - Realtek RTL8821CS, RTL8851B, RTL8852BS
    - Mediatek MT7663, MT7922
    - NXP w8997
    - Actions Semi ATS2851
    - QTI WCN6855
    - Marvell 88W8997
 
  - Can:
    - STMicroelectronics bxcan stm32f429
 
 Drivers
 -------
  - Ethernet NICs:
    - Intel (1G, icg):
      - add tracking and reporting of QBV config errors.
      - add support for configuring max SDU for each Tx queue.
    - Intel (100G, ice):
      - refactor mailbox overflow detection to support Scalable IOV
      - GNSS interface optimization
    - Intel (i40e):
      - support XDP multi-buffer
    - nVidia/Mellanox:
      - add the support for linux bridge multicast offload
      - enable TC offload for egress and engress MACVLAN over bond
      - add support for VxLAN GBP encap/decap flows offload
      - extend packet offload to fully support libreswan
      - support tunnel mode in mlx5 IPsec packet offload
      - extend XDP multi-buffer support
      - support MACsec VLAN offload
      - add support for dynamic msix vectors allocation
      - drop RX page_cache and fully use page_pool
      - implement thermal zone to report NIC temperature
    - Netronome/Corigine:
      - add support for multi-zone conntrack offload
    - Solarflare/Xilinx:
      - support offloading TC VLAN push/pop actions to the MAE
      - support TC decap rules
      - support unicast PTP
 
  - Other NICs:
    - Broadcom (bnxt): enforce software based freq adjustments only
 		on shared PHC NIC
    - RealTek (r8169): refactor to addess ASPM issues during NAPI poll.
    - Micrel (lan8841): add support for PTP_PF_PEROUT
    - Cadence (macb): enable PTP unicast
    - Engleder (tsnep): add XDP socket zero-copy support
    - virtio-net: implement exact header length guest feature
    - veth: add page_pool support for page recycling
    - vxlan: add MDB data path support
    - gve: add XDP support for GQI-QPL format
    - geneve: accept every ethertype
    - macvlan: allow some packets to bypass broadcast queue
    - mana: add support for jumbo frame
 
  - Ethernet high-speed switches:
    - Microchip (sparx5): Add support for TC flower templates.
 
  - Ethernet embedded switches:
    - Broadcom (b54):
      - configure 6318 and 63268 RGMII ports
    - Marvell (mv88e6xxx):
      - faster C45 bus scan
    - Microchip:
      - lan966x:
        - add support for IS1 VCAP
        - better TX/RX from/to CPU performances
      - ksz9477: add ETS Qdisc support
      - ksz8: enhance static MAC table operations and error handling
      - sama7g5: add PTP capability
    - NXP (ocelot):
      - add support for external ports
      - add support for preemptible traffic classes
    - Texas Instruments:
      - add CPSWxG SGMII support for J7200 and J721E
 
  - Intel WiFi (iwlwifi):
    - preparation for Wi-Fi 7 EHT and multi-link support
    - EHT (Wi-Fi 7) sniffer support
    - hardware timestamping support for some devices/firwmares
    - TX beacon protection on newer hardware
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - MU-MIMO parameters support
    - ack signal support for management packets
 
  - RealTek WiFi (rtw88):
    - SDIO bus support
    - better support for some SDIO devices
      (e.g. MAC address from efuse)
 
  - RealTek WiFi (rtw89):
    - HW scan support for 8852b
    - better support for 6 GHz scanning
    - support for various newer firmware APIs
    - framework firmware backwards compatibility
 
  - MediaTek WiFi (mt76):
    - P2P support
    - mesh A-MSDU support
    - EHT (Wi-Fi 7) support
    - coredump support
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEEg1AjqC77wbdLX2LbKSR5jcyPE6QFAmRI/mUSHHBhYmVuaUBy
 ZWRoYXQuY29tAAoJECkkeY3MjxOkgO0QAJGxpuN67YgYV0BIM+/atWKEEexJYG7B
 9MMpU4jMO3EW/pUS5t7VRsBLUybLYVPmqCZoHodObDfnu59jiPOegb6SikJv/ZwJ
 Zw62PVk5MvDnQjlu4e6kDcGwkplteN08TlgI+a49BUTedpdFitrxHAYGW8f2fRO6
 cK2XSld+ZucMoym5vRwf8yWS1BwdxnslPMxDJ+/8ZbWBZv44qAnG2vMB/kIx7ObC
 Vel/4m6MzTwVsLYBsRvcwMVbNNlZ9GuhztlTzEbfGA4ZhTadIAMgb5VTWXB84Ws7
 Aic5wTdli+q+x6/2cxhbyeoVuB9HHObYmLBAciGg4GNljP5rnQBY3X3+KVZ/x9TI
 HQB7CmhxmAZVrO9pLARFV+ECrMTH2/dy3NyrZ7uYQ3WPOXJi8hJZjOTO/eeEGL7C
 eTjdz0dZBWIBK2gON/6s4nExXVQUTEF2ZsPi52jTTClKjfe5pz/ddeFQIWaY1DTm
 pInEiWPAvd28JyiFmhFNHsuIBCjX/Zqe2JuMfMBeBibDAC09o/OGdKJYUI15AiRf
 F46Pdb7use/puqfrYW44kSAfaPYoBiE+hj1RdeQfen35xD9HVE4vdnLNeuhRlFF9
 aQfyIRHYQofkumRDr5f8JEY66cl9NiKQ4IVW1xxQfYDNdC6wQqREPG1md7rJVMrJ
 vP7ugFnttneg
 =ITVa
 -----END PGP SIGNATURE-----

Merge tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Paolo Abeni:
 "Core:

   - Introduce a config option to tweak MAX_SKB_FRAGS. Increasing the
     default value allows for better BIG TCP performances

   - Reduce compound page head access for zero-copy data transfers

   - RPS/RFS improvements, avoiding unneeded NET_RX_SOFTIRQ when
     possible

   - Threaded NAPI improvements, adding defer skb free support and
     unneeded softirq avoidance

   - Address dst_entry reference count scalability issues, via false
     sharing avoidance and optimize refcount tracking

   - Add lockless accesses annotation to sk_err[_soft]

   - Optimize again the skb struct layout

   - Extends the skb drop reasons to make it usable by multiple
     subsystems

   - Better const qualifier awareness for socket casts

  BPF:

   - Add skb and XDP typed dynptrs which allow BPF programs for more
     ergonomic and less brittle iteration through data and
     variable-sized accesses

   - Add a new BPF netfilter program type and minimal support to hook
     BPF programs to netfilter hooks such as prerouting or forward

   - Add more precise memory usage reporting for all BPF map types

   - Adds support for using {FOU,GUE} encap with an ipip device
     operating in collect_md mode and add a set of BPF kfuncs for
     controlling encap params

   - Allow BPF programs to detect at load time whether a particular
     kfunc exists or not, and also add support for this in light
     skeleton

   - Bigger batch of BPF verifier improvements to prepare for upcoming
     BPF open-coded iterators allowing for less restrictive looping
     capabilities

   - Rework RCU enforcement in the verifier, add kptr_rcu and enforce
     BPF programs to NULL-check before passing such pointers into kfunc

   - Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and
     in local storage maps

   - Enable RCU semantics for task BPF kptrs and allow referenced kptr
     tasks to be stored in BPF maps

   - Add support for refcounted local kptrs to the verifier for allowing
     shared ownership, useful for adding a node to both the BPF list and
     rbtree

   - Add BPF verifier support for ST instructions in
     convert_ctx_access() which will help new -mcpu=v4 clang flag to
     start emitting them

   - Add ARM32 USDT support to libbpf

   - Improve bpftool's visual program dump which produces the control
     flow graph in a DOT format by adding C source inline annotations

  Protocols:

   - IPv4: Allow adding to IPv4 address a 'protocol' tag. Such value
     indicates the provenance of the IP address

   - IPv6: optimize route lookup, dropping unneeded R/W lock acquisition

   - Add the handshake upcall mechanism, allowing the user-space to
     implement generic TLS handshake on kernel's behalf

   - Bridge: support per-{Port, VLAN} neighbor suppression, increasing
     resilience to nodes failures

   - SCTP: add support for Fair Capacity and Weighted Fair Queueing
     schedulers

   - MPTCP: delay first subflow allocation up to its first usage. This
     will allow for later better LSM interaction

   - xfrm: Remove inner/outer modes from input/output path. These are
     not needed anymore

   - WiFi:
      - reduced neighbor report (RNR) handling for AP mode
      - HW timestamping support
      - support for randomized auth/deauth TA for PASN privacy
      - per-link debugfs for multi-link
      - TC offload support for mac80211 drivers
      - mac80211 mesh fast-xmit and fast-rx support
      - enable Wi-Fi 7 (EHT) mesh support

  Netfilter:

   - Add nf_tables 'brouting' support, to force a packet to be routed
     instead of being bridged

   - Update bridge netfilter and ovs conntrack helpers to handle IPv6
     Jumbo packets properly, i.e. fetch the packet length from
     hop-by-hop extension header. This is needed for BIT TCP support

   - The iptables 32bit compat interface isn't compiled in by default
     anymore

   - Move ip(6)tables builtin icmp matches to the udptcp one. This has
     the advantage that icmp/icmpv6 match doesn't load the
     iptables/ip6tables modules anymore when iptables-nft is used

   - Extended netlink error report for netdevice in flowtables and
     netdev/chains. Allow for incrementally add/delete devices to netdev
     basechain. Allow to create netdev chain without device

  Driver API:

   - Remove redundant Device Control Error Reporting Enable, as PCI core
     has already error reporting enabled at enumeration time

   - Move Multicast DB netlink handlers to core, allowing devices other
     then bridge to use them

   - Allow the page_pool to directly recycle the pages from safely
     localized NAPI

   - Implement lockless TX queue stop/wake combo macros, allowing for
     further code de-duplication and sanitization

   - Add YNL support for user headers and struct attrs

   - Add partial YNL specification for devlink

   - Add partial YNL specification for ethtool

   - Add tc-mqprio and tc-taprio support for preemptible traffic classes

   - Add tx push buf len param to ethtool, specifies the maximum number
     of bytes of a transmitted packet a driver can push directly to the
     underlying device

   - Add basic LED support for switch/phy

   - Add NAPI documentation, stop relaying on external links

   - Convert dsa_master_ioctl() to netdev notifier. This is a
     preparatory work to make the hardware timestamping layer selectable
     by user space

   - Add transceiver support and improve the error messages for CAN-FD
     controllers

  New hardware / drivers:

   - Ethernet:
      - AMD/Pensando core device support
      - MediaTek MT7981 SoC
      - MediaTek MT7988 SoC
      - Broadcom BCM53134 embedded switch
      - Texas Instruments CPSW9G ethernet switch
      - Qualcomm EMAC3 DWMAC ethernet
      - StarFive JH7110 SoC
      - NXP CBTX ethernet PHY

   - WiFi:
      - Apple M1 Pro/Max devices
      - RealTek rtl8710bu/rtl8188gu
      - RealTek rtl8822bs, rtl8822cs and rtl8821cs SDIO chipset

   - Bluetooth:
      - Realtek RTL8821CS, RTL8851B, RTL8852BS
      - Mediatek MT7663, MT7922
      - NXP w8997
      - Actions Semi ATS2851
      - QTI WCN6855
      - Marvell 88W8997

   - Can:
      - STMicroelectronics bxcan stm32f429

  Drivers:

   - Ethernet NICs:
      - Intel (1G, icg):
         - add tracking and reporting of QBV config errors
         - add support for configuring max SDU for each Tx queue
      - Intel (100G, ice):
         - refactor mailbox overflow detection to support Scalable IOV
         - GNSS interface optimization
      - Intel (i40e):
         - support XDP multi-buffer
      - nVidia/Mellanox:
         - add the support for linux bridge multicast offload
         - enable TC offload for egress and engress MACVLAN over bond
         - add support for VxLAN GBP encap/decap flows offload
         - extend packet offload to fully support libreswan
         - support tunnel mode in mlx5 IPsec packet offload
         - extend XDP multi-buffer support
         - support MACsec VLAN offload
         - add support for dynamic msix vectors allocation
         - drop RX page_cache and fully use page_pool
         - implement thermal zone to report NIC temperature
      - Netronome/Corigine:
         - add support for multi-zone conntrack offload
      - Solarflare/Xilinx:
         - support offloading TC VLAN push/pop actions to the MAE
         - support TC decap rules
         - support unicast PTP

   - Other NICs:
      - Broadcom (bnxt): enforce software based freq adjustments only on
        shared PHC NIC
      - RealTek (r8169): refactor to addess ASPM issues during NAPI poll
      - Micrel (lan8841): add support for PTP_PF_PEROUT
      - Cadence (macb): enable PTP unicast
      - Engleder (tsnep): add XDP socket zero-copy support
      - virtio-net: implement exact header length guest feature
      - veth: add page_pool support for page recycling
      - vxlan: add MDB data path support
      - gve: add XDP support for GQI-QPL format
      - geneve: accept every ethertype
      - macvlan: allow some packets to bypass broadcast queue
      - mana: add support for jumbo frame

   - Ethernet high-speed switches:
      - Microchip (sparx5): Add support for TC flower templates

   - Ethernet embedded switches:
      - Broadcom (b54):
         - configure 6318 and 63268 RGMII ports
      - Marvell (mv88e6xxx):
         - faster C45 bus scan
      - Microchip:
         - lan966x:
            - add support for IS1 VCAP
            - better TX/RX from/to CPU performances
         - ksz9477: add ETS Qdisc support
         - ksz8: enhance static MAC table operations and error handling
         - sama7g5: add PTP capability
      - NXP (ocelot):
         - add support for external ports
         - add support for preemptible traffic classes
      - Texas Instruments:
         - add CPSWxG SGMII support for J7200 and J721E

   - Intel WiFi (iwlwifi):
      - preparation for Wi-Fi 7 EHT and multi-link support
      - EHT (Wi-Fi 7) sniffer support
      - hardware timestamping support for some devices/firwmares
      - TX beacon protection on newer hardware

   - Qualcomm 802.11ax WiFi (ath11k):
      - MU-MIMO parameters support
      - ack signal support for management packets

   - RealTek WiFi (rtw88):
      - SDIO bus support
      - better support for some SDIO devices (e.g. MAC address from
        efuse)

   - RealTek WiFi (rtw89):
      - HW scan support for 8852b
      - better support for 6 GHz scanning
      - support for various newer firmware APIs
      - framework firmware backwards compatibility

   - MediaTek WiFi (mt76):
      - P2P support
      - mesh A-MSDU support
      - EHT (Wi-Fi 7) support
      - coredump support"

* tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2078 commits)
  net: phy: hide the PHYLIB_LEDS knob
  net: phy: marvell-88x2222: remove unnecessary (void*) conversions
  tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.
  net: amd: Fix link leak when verifying config failed
  net: phy: marvell: Fix inconsistent indenting in led_blink_set
  lan966x: Don't use xdp_frame when action is XDP_TX
  tsnep: Add XDP socket zero-copy TX support
  tsnep: Add XDP socket zero-copy RX support
  tsnep: Move skb receive action to separate function
  tsnep: Add functions for queue enable/disable
  tsnep: Rework TX/RX queue initialization
  tsnep: Replace modulo operation with mask
  net: phy: dp83867: Add led_brightness_set support
  net: phy: Fix reading LED reg property
  drivers: nfc: nfcsim: remove return value check of `dev_dir`
  net: phy: dp83867: Remove unnecessary (void*) conversions
  net: ethtool: coalesce: try to make user settings stick twice
  net: mana: Check if netdev/napi_alloc_frag returns single page
  net: mana: Rename mana_refill_rxoob and remove some empty lines
  net: veth: add page_pool stats
  ...
2023-04-26 16:07:23 -07:00
Linus Torvalds
df45da57cb arm64 updates for 6.4
ACPI:
 	* Improve error reporting when failing to manage SDEI on AGDI device
 	  removal
 
 Assembly routines:
 	* Improve register constraints so that the compiler can make use of
 	  the zero register instead of moving an immediate #0 into a GPR
 
 	* Allow the compiler to allocate the registers used for CAS
 	  instructions
 
 CPU features and system registers:
 	* Cleanups to the way in which CPU features are identified from the
 	  ID register fields
 
 	* Extend system register definition generation to handle Enum types
 	  when defining shared register fields
 
 	* Generate definitions for new _EL2 registers and add new fields
 	  for ID_AA64PFR1_EL1
 
 	* Allow SVE to be disabled separately from SME on the kernel
 	  command-line
 
 Tracing:
 	* Support for "direct calls" in ftrace, which enables BPF tracing
 	  for arm64
 
 Kdump:
 	* Don't bother unmapping the crashkernel from the linear mapping,
 	  which then allows us to use huge (block) mappings and reduce
 	  TLB pressure when a crashkernel is loaded.
 
 Memory management:
 	* Try again to remove data cache invalidation from the coherent DMA
 	  allocation path
 
 	* Simplify the fixmap code by mapping at page granularity
 
 	* Allow the kfence pool to be allocated early, preventing the rest
 	  of the linear mapping from being forced to page granularity
 
 Perf and PMU:
 	* Move CPU PMU code out to drivers/perf/ where it can be reused
 	  by the 32-bit ARM architecture when running on ARMv8 CPUs
 
 	* Fix race between CPU PMU probing and pKVM host de-privilege
 
 	* Add support for Apple M2 CPU PMU
 
 	* Adjust the generic PERF_COUNT_HW_BRANCH_INSTRUCTIONS event
 	  dynamically, depending on what the CPU actually supports
 
 	* Minor fixes and cleanups to system PMU drivers
 
 Stack tracing:
 	* Use the XPACLRI instruction to strip PAC from pointers, rather
 	  than rolling our own function in C
 
 	* Remove redundant PAC removal for toolchains that handle this in
 	  their builtins
 
 	* Make backtracing more resilient in the face of instrumentation
 
 Miscellaneous:
 	* Fix single-step with KGDB
 
 	* Remove harmless warning when 'nokaslr' is passed on the kernel
 	  command-line
 
 	* Minor fixes and cleanups across the board
 -----BEGIN PGP SIGNATURE-----
 
 iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAmRChcwQHHdpbGxAa2Vy
 bmVsLm9yZwAKCRC3rHDchMFjNCgBCADFvkYY9ESztSnd3EpiMbbAzgRCQBiA5H7U
 F2Wc+hIWgeAeUEttSH22+F16r6Jb0gbaDvsuhtN2W/rwQhKNbCU0MaUME05MPmg2
 AOp+RZb2vdT5i5S5dC6ZM6G3T6u9O78LBWv2JWBdd6RIybamEn+RL00ep2WAduH7
 n1FgTbsKgnbScD2qd4K1ejZ1W/BQMwYulkNpyTsmCIijXM12lkzFlxWnMtky3uhR
 POpawcIZzXvWI02QAX+SIdynGChQV3VP+dh9GuFbt7ASigDEhgunvfUYhZNSaqf4
 +/q0O8toCtmQJBUhF0DEDSB5T8SOz5v9CKxKuwfaX6Trq0ixFQpZ
 =78L9
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "ACPI:

   - Improve error reporting when failing to manage SDEI on AGDI device
     removal

  Assembly routines:

   - Improve register constraints so that the compiler can make use of
     the zero register instead of moving an immediate #0 into a GPR

   - Allow the compiler to allocate the registers used for CAS
     instructions

  CPU features and system registers:

   - Cleanups to the way in which CPU features are identified from the
     ID register fields

   - Extend system register definition generation to handle Enum types
     when defining shared register fields

   - Generate definitions for new _EL2 registers and add new fields for
     ID_AA64PFR1_EL1

   - Allow SVE to be disabled separately from SME on the kernel
     command-line

  Tracing:

   - Support for "direct calls" in ftrace, which enables BPF tracing for
     arm64

  Kdump:

   - Don't bother unmapping the crashkernel from the linear mapping,
     which then allows us to use huge (block) mappings and reduce TLB
     pressure when a crashkernel is loaded.

  Memory management:

   - Try again to remove data cache invalidation from the coherent DMA
     allocation path

   - Simplify the fixmap code by mapping at page granularity

   - Allow the kfence pool to be allocated early, preventing the rest of
     the linear mapping from being forced to page granularity

  Perf and PMU:

   - Move CPU PMU code out to drivers/perf/ where it can be reused by
     the 32-bit ARM architecture when running on ARMv8 CPUs

   - Fix race between CPU PMU probing and pKVM host de-privilege

   - Add support for Apple M2 CPU PMU

   - Adjust the generic PERF_COUNT_HW_BRANCH_INSTRUCTIONS event
     dynamically, depending on what the CPU actually supports

   - Minor fixes and cleanups to system PMU drivers

  Stack tracing:

   - Use the XPACLRI instruction to strip PAC from pointers, rather than
     rolling our own function in C

   - Remove redundant PAC removal for toolchains that handle this in
     their builtins

   - Make backtracing more resilient in the face of instrumentation

  Miscellaneous:

   - Fix single-step with KGDB

   - Remove harmless warning when 'nokaslr' is passed on the kernel
     command-line

   - Minor fixes and cleanups across the board"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (72 commits)
  KVM: arm64: Ensure CPU PMU probes before pKVM host de-privilege
  arm64: kexec: include reboot.h
  arm64: delete dead code in this_cpu_set_vectors()
  arm64/cpufeature: Use helper macro to specify ID register for capabilites
  drivers/perf: hisi: add NULL check for name
  drivers/perf: hisi: Remove redundant initialized of pmu->name
  arm64/cpufeature: Consistently use symbolic constants for min_field_value
  arm64/cpufeature: Pull out helper for CPUID register definitions
  arm64/sysreg: Convert HFGITR_EL2 to automatic generation
  ACPI: AGDI: Improve error reporting for problems during .remove()
  arm64: kernel: Fix kernel warning when nokaslr is passed to commandline
  perf/arm-cmn: Fix port detection for CMN-700
  arm64: kgdb: Set PSTATE.SS to 1 to re-enable single-step
  arm64: move PAC masks to <asm/pointer_auth.h>
  arm64: use XPACLRI to strip PAC
  arm64: avoid redundant PAC stripping in __builtin_return_address()
  arm64/sme: Fix some comments of ARM SME
  arm64/signal: Alloc tpidr2 sigframe after checking system_supports_tpidr2()
  arm64/signal: Use system_supports_tpidr2() to check TPIDR2
  arm64/idreg: Don't disable SME when disabling SVE
  ...
2023-04-25 12:39:01 -07:00
Linus Torvalds
ef36b9afc2 fget() to fdget() conversions
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCZEYCQAAKCRBZ7Krx/gZQ
 64FdAQDZ2hTDyZEWPt486dWYPYpiKyaGFXSXDGo7wgP0fiwxXQEA/mROKb6JqYw6
 27mZ9A7qluT8r3AfTTQ0D+Yse/dr4AM=
 =GA9W
 -----END PGP SIGNATURE-----

Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs fget updates from Al Viro:
 "fget() to fdget() conversions"

* tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fuse_dev_ioctl(): switch to fdget()
  cgroup_get_from_fd(): switch to fdget_raw()
  bpf: switch to fdget_raw()
  build_mount_idmapped(): switch to fdget()
  kill the last remaining user of proc_ns_fget()
  SVM-SEV: convert the rest of fget() uses to fdget() in there
  convert sgx_set_attribute() to fdget()/fdput()
  convert setns(2) to fdget()/fdput()
2023-04-24 19:14:20 -07:00