linux.git/net/core/sock.c, branch v6.12 Linux kernel source tree net: fix SO_DEVMEM_DONTNEED looping too long 2024-11-12T02:11:46+00:00 Mina Almasry almasrymina@google.com 2024-11-07T21:03:30+00:00 f2685c00c3222305f5b6740a8b16ea044640283a Exit early if we're freeing more than 1024 frags, to prevent looping too long. Also minor code cleanups: - Flip checks to reduce indentation. - Use sizeof(*tokens) everywhere for consistentcy. Cc: Yi Lai <yi1.lai@linux.intel.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20241107210331.3044434-1-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Exit early if we're freeing more than 1024 frags, to prevent
looping too long.

Also minor code cleanups:
- Flip checks to reduce indentation.
- Use sizeof(*tokens) everywhere for consistentcy.

Cc: Yi Lai <yi1.lai@linux.intel.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20241107210331.3044434-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
move asm/unaligned.h to linux/unaligned.h 2024-10-02T21:23:23+00:00 Al Viro viro@zeniv.linux.org.uk 2024-10-01T19:35:57+00:00 5f60d5f6bbc12e782fac78110b0ee62698f3b576 asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h 
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
Merge tag 'vfs-6.12.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs 2024-09-16T07:14:02+00:00 Linus Torvalds torvalds@linux-foundation.org 2024-09-16T07:14:02+00:00 3352633ce6b221d64bf40644d412d9670e7d56e3 Pull vfs file updates from Christian Brauner: "This is the work to cleanup and shrink struct file significantly. Right now, (focusing on x86) struct file is 232 bytes. After this series struct file will be 184 bytes aka 3 cacheline and a spare 8 bytes for future extensions at the end of the struct. With struct file being as ubiquitous as it is this should make a difference for file heavy workloads and allow further optimizations in the future. - struct fown_struct was embedded into struct file letting it take up 32 bytes in total when really it shouldn't even be embedded in struct file in the first place. Instead, actual users of struct fown_struct now allocate the struct on demand. This frees up 24 bytes. - Move struct file_ra_state into the union containg the cleanup hooks and move f_iocb_flags out of the union. This closes a 4 byte hole we created earlier and brings struct file to 192 bytes. Which means struct file is 3 cachelines and we managed to shrink it by 40 bytes. - Reorder struct file so that nothing crosses a cacheline. I suspect that in the future we will end up reordering some members to mitigate false sharing issues or just because someone does actually provide really good perf data. - Shrinking struct file to 192 bytes is only part of the work. Files use a slab that is SLAB_TYPESAFE_BY_RCU and when a kmem cache is created with SLAB_TYPESAFE_BY_RCU the free pointer must be located outside of the object because the cache doesn't know what part of the memory can safely be overwritten as it may be needed to prevent object recycling. That has the consequence that SLAB_TYPESAFE_BY_RCU may end up adding a new cacheline. So this also contains work to add a new kmem_cache_create_rcu() function that allows the caller to specify an offset where the freelist pointer is supposed to be placed. Thus avoiding the implicit addition of a fourth cacheline. - And finally this removes the f_version member in struct file. The f_version member isn't particularly well-defined. It is mainly used as a cookie to detect concurrent seeks when iterating directories. But it is also abused by some subsystems for completely unrelated things. It is mostly a directory and filesystem specific thing that doesn't really need to live in struct file and with its wonky semantics it really lacks a specific function. For pipes, f_version is (ab)used to defer poll notifications until a write has happened. And struct pipe_inode_info is used by multiple struct files in their ->private_data so there's no chance of pushing that down into file->private_data without introducing another pointer indirection. But pipes don't rely on f_pos_lock so this adds a union into struct file encompassing f_pos_lock and a pipe specific f_pipe member that pipes can use. This union of course can be extended to other file types and is similar to what we do in struct inode already" * tag 'vfs-6.12.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits) fs: remove f_version pipe: use f_pipe fs: add f_pipe ubifs: store cookie in private data ufs: store cookie in private data udf: store cookie in private data proc: store cookie in private data ocfs2: store cookie in private data input: remove f_version abuse ext4: store cookie in private data ext2: store cookie in private data affs: store cookie in private data fs: add generic_llseek_cookie() fs: use must_set_pos() fs: add must_set_pos() fs: add vfs_setpos_cookie() s390: remove unused f_version ceph: remove unused f_version adi: remove unused f_version mm: Removed @freeptr_offset to prevent doc warning ... 
Pull vfs file updates from Christian Brauner:
 "This is the work to cleanup and shrink struct file significantly.

  Right now, (focusing on x86) struct file is 232 bytes. After this
  series struct file will be 184 bytes aka 3 cacheline and a spare 8
  bytes for future extensions at the end of the struct.

  With struct file being as ubiquitous as it is this should make a
  difference for file heavy workloads and allow further optimizations in
  the future.

   - struct fown_struct was embedded into struct file letting it take up
     32 bytes in total when really it shouldn't even be embedded in
     struct file in the first place. Instead, actual users of struct
     fown_struct now allocate the struct on demand. This frees up 24
     bytes.

   - Move struct file_ra_state into the union containg the cleanup hooks
     and move f_iocb_flags out of the union. This closes a 4 byte hole
     we created earlier and brings struct file to 192 bytes. Which means
     struct file is 3 cachelines and we managed to shrink it by 40
     bytes.

   - Reorder struct file so that nothing crosses a cacheline.

     I suspect that in the future we will end up reordering some members
     to mitigate false sharing issues or just because someone does
     actually provide really good perf data.

   - Shrinking struct file to 192 bytes is only part of the work.

     Files use a slab that is SLAB_TYPESAFE_BY_RCU and when a kmem cache
     is created with SLAB_TYPESAFE_BY_RCU the free pointer must be
     located outside of the object because the cache doesn't know what
     part of the memory can safely be overwritten as it may be needed to
     prevent object recycling.

     That has the consequence that SLAB_TYPESAFE_BY_RCU may end up
     adding a new cacheline.

     So this also contains work to add a new kmem_cache_create_rcu()
     function that allows the caller to specify an offset where the
     freelist pointer is supposed to be placed. Thus avoiding the
     implicit addition of a fourth cacheline.

   - And finally this removes the f_version member in struct file.

     The f_version member isn't particularly well-defined. It is mainly
     used as a cookie to detect concurrent seeks when iterating
     directories. But it is also abused by some subsystems for
     completely unrelated things.

     It is mostly a directory and filesystem specific thing that doesn't
     really need to live in struct file and with its wonky semantics it
     really lacks a specific function.

     For pipes, f_version is (ab)used to defer poll notifications until
     a write has happened. And struct pipe_inode_info is used by
     multiple struct files in their ->private_data so there's no chance
     of pushing that down into file->private_data without introducing
     another pointer indirection.

     But pipes don't rely on f_pos_lock so this adds a union into struct
     file encompassing f_pos_lock and a pipe specific f_pipe member that
     pipes can use. This union of course can be extended to other file
     types and is similar to what we do in struct inode already"

* tag 'vfs-6.12.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
  fs: remove f_version
  pipe: use f_pipe
  fs: add f_pipe
  ubifs: store cookie in private data
  ufs: store cookie in private data
  udf: store cookie in private data
  proc: store cookie in private data
  ocfs2: store cookie in private data
  input: remove f_version abuse
  ext4: store cookie in private data
  ext2: store cookie in private data
  affs: store cookie in private data
  fs: add generic_llseek_cookie()
  fs: use must_set_pos()
  fs: add must_set_pos()
  fs: add vfs_setpos_cookie()
  s390: remove unused f_version
  ceph: remove unused f_version
  adi: remove unused f_version
  mm: Removed @freeptr_offset to prevent doc warning
  ...
net: add SO_DEVMEM_DONTNEED setsockopt to release RX frags 2024-09-12T03:44:32+00:00 Mina Almasry almasrymina@google.com 2024-09-10T17:14:54+00:00 678f6e28b5f6fc2316f2c0fed8f8903101f1e128 Add an interface for the user to notify the kernel that it is done reading the devmem dmabuf frags returned as cmsg. The kernel will drop the reference on the frags to make them available for reuse. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20240910171458.219195-11-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Add an interface for the user to notify the kernel that it is done
reading the devmem dmabuf frags returned as cmsg. The kernel will
drop the reference on the frags to make them available for reuse.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20240910171458.219195-11-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
file: reclaim 24 bytes from f_owner 2024-08-28T11:05:39+00:00 Christian Brauner brauner@kernel.org 2024-08-09T16:00:01+00:00 1934b212615dc617ac84fc306333ab2b9fc3b04f We do embedd struct fown_struct into struct file letting it take up 32 bytes in total. We could tweak struct fown_struct to be more compact but really it shouldn't even be embedded in struct file in the first place. Instead, actual users of struct fown_struct should allocate the struct on demand. This frees up 24 bytes in struct file. That will have some potentially user-visible changes for the ownership fcntl()s. Some of them can now fail due to allocation failures. Practically, that probably will almost never happen as the allocations are small and they only happen once per file. The fown_struct is used during kill_fasync() which is used by e.g., pipes to generate a SIGIO signal. Sending of such signals is conditional on userspace having set an owner for the file using one of the F_OWNER fcntl()s. Such users will be unaffected if struct fown_struct is allocated during the fcntl() call. There are a few subsystems that call __f_setown() expecting file->f_owner to be allocated: (1) tun devices file->f_op->fasync::tun_chr_fasync() -> __f_setown() There are no callers of tun_chr_fasync(). (2) tty devices file->f_op->fasync::tty_fasync() -> __tty_fasync() -> __f_setown() tty_fasync() has no additional callers but __tty_fasync() has. Note that __tty_fasync() only calls __f_setown() if the @on argument is true. It's called from: file->f_op->release::tty_release() -> tty_release() -> __tty_fasync() -> __f_setown() tty_release() calls __tty_fasync() with @on false => __f_setown() is never called from tty_release(). => All callers of tty_release() are safe as well. file->f_op->release::tty_open() -> tty_release() -> __tty_fasync() -> __f_setown() __tty_hangup() calls __tty_fasync() with @on false => __f_setown() is never called from tty_release(). => All callers of __tty_hangup() are safe as well. From the callchains it's obvious that (1) and (2) end up getting called via file->f_op->fasync(). That can happen either through the F_SETFL fcntl() with the FASYNC flag raised or via the FIOASYNC ioctl(). If FASYNC is requested and the file isn't already FASYNC then file->f_op->fasync() is called with @on true which ends up causing both (1) and (2) to call __f_setown(). (1) and (2) are the only subsystems that call __f_setown() from the file->f_op->fasync() handler. So both (1) and (2) have been updated to allocate a struct fown_struct prior to calling fasync_helper() to register with the fasync infrastructure. That's safe as they both call fasync_helper() which also does allocations if @on is true. The other interesting case are file leases: (3) file leases lease_manager_ops->lm_setup::lease_setup() -> __f_setown() Which in turn is called from: generic_add_lease() -> lease_manager_ops->lm_setup::lease_setup() -> __f_setown() So here again we can simply make generic_add_lease() allocate struct fown_struct prior to the lease_manager_ops->lm_setup::lease_setup() which happens under a spinlock. With that the two remaining subsystems that call __f_setown() are: (4) dnotify (5) sockets Both have their own custom ioctls to set struct fown_struct and both have been converted to allocate a struct fown_struct on demand from their respective ioctls. Interactions with O_PATH are fine as well e.g., when opening a /dev/tty as O_PATH then no file->f_op->open() happens thus no file->f_owner is allocated. That's fine as no file operation will be set for those and the device has never been opened. fcntl()s called on such things will just allocate a ->f_owner on demand. Although I have zero idea why'd you care about f_owner on an O_PATH fd. Link: https://lore.kernel.org/r/20240813-work-f_owner-v2-1-4e9343a79f9f@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> 
We do embedd struct fown_struct into struct file letting it take up 32
bytes in total. We could tweak struct fown_struct to be more compact but
really it shouldn't even be embedded in struct file in the first place.

Instead, actual users of struct fown_struct should allocate the struct
on demand. This frees up 24 bytes in struct file.

That will have some potentially user-visible changes for the ownership
fcntl()s. Some of them can now fail due to allocation failures.
Practically, that probably will almost never happen as the allocations
are small and they only happen once per file.

The fown_struct is used during kill_fasync() which is used by e.g.,
pipes to generate a SIGIO signal. Sending of such signals is conditional
on userspace having set an owner for the file using one of the F_OWNER
fcntl()s. Such users will be unaffected if struct fown_struct is
allocated during the fcntl() call.

There are a few subsystems that call __f_setown() expecting
file->f_owner to be allocated:

(1) tun devices
    file->f_op->fasync::tun_chr_fasync()
    -> __f_setown()

    There are no callers of tun_chr_fasync().

(2) tty devices

    file->f_op->fasync::tty_fasync()
    -> __tty_fasync()
       -> __f_setown()

    tty_fasync() has no additional callers but __tty_fasync() has. Note
    that __tty_fasync() only calls __f_setown() if the @on argument is
    true. It's called from:

    file->f_op->release::tty_release()
    -> tty_release()
       -> __tty_fasync()
          -> __f_setown()

    tty_release() calls __tty_fasync() with @on false
    => __f_setown() is never called from tty_release().
       => All callers of tty_release() are safe as well.

    file->f_op->release::tty_open()
    -> tty_release()
       -> __tty_fasync()
          -> __f_setown()

    __tty_hangup() calls __tty_fasync() with @on false
    => __f_setown() is never called from tty_release().
       => All callers of __tty_hangup() are safe as well.

From the callchains it's obvious that (1) and (2) end up getting called
via file->f_op->fasync(). That can happen either through the F_SETFL
fcntl() with the FASYNC flag raised or via the FIOASYNC ioctl(). If
FASYNC is requested and the file isn't already FASYNC then
file->f_op->fasync() is called with @on true which ends up causing both
(1) and (2) to call __f_setown().

(1) and (2) are the only subsystems that call __f_setown() from the
file->f_op->fasync() handler. So both (1) and (2) have been updated to
allocate a struct fown_struct prior to calling fasync_helper() to
register with the fasync infrastructure. That's safe as they both call
fasync_helper() which also does allocations if @on is true.

The other interesting case are file leases:

(3) file leases
    lease_manager_ops->lm_setup::lease_setup()
    -> __f_setown()

    Which in turn is called from:

    generic_add_lease()
    -> lease_manager_ops->lm_setup::lease_setup()
       -> __f_setown()

So here again we can simply make generic_add_lease() allocate struct
fown_struct prior to the lease_manager_ops->lm_setup::lease_setup()
which happens under a spinlock.

With that the two remaining subsystems that call __f_setown() are:

(4) dnotify
(5) sockets

Both have their own custom ioctls to set struct fown_struct and both
have been converted to allocate a struct fown_struct on demand from
their respective ioctls.

Interactions with O_PATH are fine as well e.g., when opening a /dev/tty
as O_PATH then no file->f_op->open() happens thus no file->f_owner is
allocated. That's fine as no file operation will be set for those and
the device has never been opened. fcntl()s called on such things will
just allocate a ->f_owner on demand. Although I have zero idea why'd you
care about f_owner on an O_PATH fd.

Link: https://lore.kernel.org/r/20240813-work-f_owner-v2-1-4e9343a79f9f@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
net: Correct spelling in net/core 2024-08-26T16:37:23+00:00 Simon Horman horms@kernel.org 2024-08-22T12:57:34+00:00 a8c924e98738f77668b022ec34107ca8b6093392 Correct spelling in net/core. As reported by codespell. Signed-off-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20240822-net-spell-v1-13-3a98971ce2d2@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Correct spelling in net/core.
As reported by codespell.

Signed-off-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240822-net-spell-v1-13-3a98971ce2d2@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-06-20T20:49:59+00:00 Jakub Kicinski kuba@kernel.org 2024-06-20T20:02:22+00:00 a6ec08beec9ea93f342d6daeac922208709694dc Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt.c 1e7962114c10 ("bnxt_en: Restore PTP tx_avail count in case of skb_pad() error") 165f87691a89 ("bnxt_en: add timestamping statistics support") No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  1e7962114c10 ("bnxt_en: Restore PTP tx_avail count in case of skb_pad() error")
  165f87691a89 ("bnxt_en: add timestamping statistics support")

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: do not leave a dangling sk pointer, when socket creation fails 2024-06-20T08:43:14+00:00 Ignat Korchagin ignat@cloudflare.com 2024-06-17T21:02:05+00:00 6cd4a78d962bebbaf8beb7d2ead3f34120e3f7b2 It is possible to trigger a use-after-free by: * attaching an fentry probe to __sock_release() and the probe calling the bpf_get_socket_cookie() helper * running traceroute -I 1.1.1.1 on a freshly booted VM A KASAN enabled kernel will log something like below (decoded and stripped): ================================================================== BUG: KASAN: slab-use-after-free in __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29) Read of size 8 at addr ffff888007110dd8 by task traceroute/299 CPU: 2 PID: 299 Comm: traceroute Tainted: G E 6.10.0-rc2+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:117 (discriminator 1)) print_report (mm/kasan/report.c:378 mm/kasan/report.c:488) ? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29) kasan_report (mm/kasan/report.c:603) ? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29) kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29) bpf_get_socket_ptr_cookie (./arch/x86/include/asm/preempt.h:94 ./include/linux/sock_diag.h:42 net/core/filter.c:5094 net/core/filter.c:5092) bpf_prog_875642cf11f1d139___sock_release+0x6e/0x8e bpf_trampoline_6442506592+0x47/0xaf __sock_release (net/socket.c:652) __sock_create (net/socket.c:1601) ... Allocated by task 299 on cpu 2 at 78.328492s: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:68) __kasan_slab_alloc (mm/kasan/common.c:312 mm/kasan/common.c:338) kmem_cache_alloc_noprof (mm/slub.c:3941 mm/slub.c:4000 mm/slub.c:4007) sk_prot_alloc (net/core/sock.c:2075) sk_alloc (net/core/sock.c:2134) inet_create (net/ipv4/af_inet.c:327 net/ipv4/af_inet.c:252) __sock_create (net/socket.c:1572) __sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706) __x64_sys_socket (net/socket.c:1718) do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Freed by task 299 on cpu 2 at 78.328502s: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:68) kasan_save_free_info (mm/kasan/generic.c:582) poison_slab_object (mm/kasan/common.c:242) __kasan_slab_free (mm/kasan/common.c:256) kmem_cache_free (mm/slub.c:4437 mm/slub.c:4511) __sk_destruct (net/core/sock.c:2117 net/core/sock.c:2208) inet_create (net/ipv4/af_inet.c:397 net/ipv4/af_inet.c:252) __sock_create (net/socket.c:1572) __sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706) __x64_sys_socket (net/socket.c:1718) do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Fix this by clearing the struct socket reference in sk_common_release() to cover all protocol families create functions, which may already attached the reference to the sk object with sock_init_data(). Fixes: c5dbb89fc2ac ("bpf: Expose bpf_get_socket_cookie to tracing programs") Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/netdev/20240613194047.36478-1-kuniyu@amazon.com/T/ Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: D. Wythe <alibuda@linux.alibaba.com> Link: https://lore.kernel.org/r/20240617210205.67311-1-ignat@cloudflare.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
It is possible to trigger a use-after-free by:
  * attaching an fentry probe to __sock_release() and the probe calling the
    bpf_get_socket_cookie() helper
  * running traceroute -I 1.1.1.1 on a freshly booted VM

A KASAN enabled kernel will log something like below (decoded and stripped):
==================================================================
BUG: KASAN: slab-use-after-free in __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
Read of size 8 at addr ffff888007110dd8 by task traceroute/299

CPU: 2 PID: 299 Comm: traceroute Tainted: G            E      6.10.0-rc2+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
dump_stack_lvl (lib/dump_stack.c:117 (discriminator 1))
print_report (mm/kasan/report.c:378 mm/kasan/report.c:488)
? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
kasan_report (mm/kasan/report.c:603)
? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189)
__sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
bpf_get_socket_ptr_cookie (./arch/x86/include/asm/preempt.h:94 ./include/linux/sock_diag.h:42 net/core/filter.c:5094 net/core/filter.c:5092)
bpf_prog_875642cf11f1d139___sock_release+0x6e/0x8e
bpf_trampoline_6442506592+0x47/0xaf
__sock_release (net/socket.c:652)
__sock_create (net/socket.c:1601)
...
Allocated by task 299 on cpu 2 at 78.328492s:
kasan_save_stack (mm/kasan/common.c:48)
kasan_save_track (mm/kasan/common.c:68)
__kasan_slab_alloc (mm/kasan/common.c:312 mm/kasan/common.c:338)
kmem_cache_alloc_noprof (mm/slub.c:3941 mm/slub.c:4000 mm/slub.c:4007)
sk_prot_alloc (net/core/sock.c:2075)
sk_alloc (net/core/sock.c:2134)
inet_create (net/ipv4/af_inet.c:327 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1572)
__sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706)
__x64_sys_socket (net/socket.c:1718)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Freed by task 299 on cpu 2 at 78.328502s:
kasan_save_stack (mm/kasan/common.c:48)
kasan_save_track (mm/kasan/common.c:68)
kasan_save_free_info (mm/kasan/generic.c:582)
poison_slab_object (mm/kasan/common.c:242)
__kasan_slab_free (mm/kasan/common.c:256)
kmem_cache_free (mm/slub.c:4437 mm/slub.c:4511)
__sk_destruct (net/core/sock.c:2117 net/core/sock.c:2208)
inet_create (net/ipv4/af_inet.c:397 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1572)
__sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706)
__x64_sys_socket (net/socket.c:1718)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Fix this by clearing the struct socket reference in sk_common_release() to cover
all protocol families create functions, which may already attached the
reference to the sk object with sock_init_data().

Fixes: c5dbb89fc2ac ("bpf: Expose bpf_get_socket_cookie to tracing programs")
Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/20240613194047.36478-1-kuniyu@amazon.com/T/
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: D. Wythe <alibuda@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240617210205.67311-1-ignat@cloudflare.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: validate SO_TXTIME clockid coming from userspace 2024-06-01T22:47:23+00:00 Abhishek Chauhan quic_abchauha@quicinc.com 2024-05-29T18:31:30+00:00 73451e9aaa24e8e44cb91e5fd6b59bf53e069c1f Currently there are no strict checks while setting SO_TXTIME from userspace. With the recent development in skb->tstamp_type clockid with unsupported clocks results in warn_on_once, which causes unnecessary aborts in some systems which enables panic on warns. Add validation in setsockopt to support only CLOCK_REALTIME, CLOCK_MONOTONIC and CLOCK_TAI to be set from userspace. Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@linux.dev/ Link: https://lore.kernel.org/lkml/6bdba7b6-fd22-4ea5-a356-12268674def1@quicinc.com/ Fixes: 1693c5db6ab8 ("net: Add additional bit to support clockid_t timestamp type") Reported-by: syzbot+d7b227731ec589e7f4f0@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d7b227731ec589e7f4f0 Reported-by: syzbot+30a35a2e9c5067cc43fa@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=30a35a2e9c5067cc43fa Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com> Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240529183130.1717083-1-quic_abchauha@quicinc.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Currently there are no strict checks while setting SO_TXTIME
from userspace. With the recent development in skb->tstamp_type
clockid with unsupported clocks results in warn_on_once, which causes
unnecessary aborts in some systems which enables panic on warns.

Add validation in setsockopt to support only CLOCK_REALTIME,
CLOCK_MONOTONIC and CLOCK_TAI to be set from userspace.

Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@linux.dev/
Link: https://lore.kernel.org/lkml/6bdba7b6-fd22-4ea5-a356-12268674def1@quicinc.com/
Fixes: 1693c5db6ab8 ("net: Add additional bit to support clockid_t timestamp type")
Reported-by: syzbot+d7b227731ec589e7f4f0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d7b227731ec589e7f4f0
Reported-by: syzbot+30a35a2e9c5067cc43fa@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=30a35a2e9c5067cc43fa
Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240529183130.1717083-1-quic_abchauha@quicinc.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net/core: move the lockdep-init of sk_callback_lock to sk_init_common() 2024-05-28T11:29:36+00:00 Gou Hao gouhao@uniontech.com 2024-05-26T14:57:18+00:00 de31e96cf423848a1d541142446801430c12da3c In commit cdfbabfb2f0c ("net: Work around lockdep limitation in sockets that use sockets"), it introduces 'af_kern_callback_keys' to lockdep-init of sk_callback_lock according to 'sk_kern_sock', it modifies sock_init_data() only, and sk_clone_lock() calls sk_init_common() to initialize sk_callback_lock too, so the lockdep-init of sk_callback_lock should be moved to sk_init_common(). Signed-off-by: Gou Hao <gouhao@uniontech.com> Link: https://lore.kernel.org/r/20240526145718.9542-2-gouhao@uniontech.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
In commit cdfbabfb2f0c ("net: Work around lockdep limitation in
sockets that use sockets"), it introduces 'af_kern_callback_keys'
to lockdep-init of sk_callback_lock according to 'sk_kern_sock',
it modifies sock_init_data() only, and sk_clone_lock() calls
sk_init_common() to initialize sk_callback_lock too, so the
lockdep-init of sk_callback_lock should be moved to sk_init_common().

Signed-off-by: Gou Hao <gouhao@uniontech.com>
Link: https://lore.kernel.org/r/20240526145718.9542-2-gouhao@uniontech.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>