Hello,
syzbot found the following issue on:
HEAD commit: 551acdc3c3d2 Merge tag 'net-5.17-final' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=131b279d700000
kernel config: https://syzkaller.appspot.com/x/.config?x=d35f9bc6884af6c9
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11dbf961700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f5b119700000
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1163699d700000
final oops: https://syzkaller.appspot.com/x/report.txt?x=1363699d700000
console output: https://syzkaller.appspot.com/x/log.txt?x=1563699d700000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x3f2f/0x56c0 kernel/locking/lockdep.c:4897
Read of size 8 at addr ffff88807bc048a8 by task syz-executor399/3618
CPU: 1 PID: 3618 Comm: syz-executor399 Not tainted 5.17.0-rc8-syzkaller-00045-g551acdc3c3d2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
__kasan_report mm/kasan/report.c:442 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
__lock_acquire+0x3f2f/0x56c0 kernel/locking/lockdep.c:4897
lock_acquire kernel/locking/lockdep.c:5639 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:374 [inline]
post_one_notification.isra.0+0x59/0x830 kernel/watch_queue.c:86
__post_watch_notification kernel/watch_queue.c:206 [inline]
__post_watch_notification+0x561/0x840 kernel/watch_queue.c:176
post_watch_notification include/linux/watch_queue.h:109 [inline]
notify_key security/keys/internal.h:199 [inline]
__key_update security/keys/key.c:775 [inline]
key_create_or_update+0xdbf/0xde0 security/keys/key.c:979
__do_sys_add_key+0x215/0x430 security/keys/keyctl.c:134
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f53132c8a89
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f531327a2f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 00007f5313350428 RCX: 00007f53132c8a89
RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000020000040
RBP: 0000000000000000 R08: 00000000fffffffc R09: 0000000000000000
R10: 0000000000000048 R11: 0000000000000246 R12: 00007f5313350420
R13: 00007f531335042c R14: 00007f531331e074 R15: 3a74707972637366
</TASK>
Allocated by task 3615:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:436 [inline]
____kasan_kmalloc mm/kasan/common.c:515 [inline]
____kasan_kmalloc mm/kasan/common.c:474 [inline]
__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
alloc_pipe_info+0x105/0x590 fs/pipe.c:790
get_pipe_inode fs/pipe.c:881 [inline]
create_pipe_files+0x8d/0x880 fs/pipe.c:913
__do_pipe_flags fs/pipe.c:962 [inline]
do_pipe2+0x96/0x1b0 fs/pipe.c:1010
__do_sys_pipe2 fs/pipe.c:1028 [inline]
__se_sys_pipe2 fs/pipe.c:1026 [inline]
__x64_sys_pipe2+0x50/0x70 fs/pipe.c:1026
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
Freed by task 3616:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:45
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:366 [inline]
____kasan_slab_free+0x126/0x160 mm/kasan/common.c:328
kasan_slab_free include/linux/kasan.h:236 [inline]
slab_free_hook mm/slub.c:1728 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754
slab_free mm/slub.c:3509 [inline]
kfree+0xd0/0x390 mm/slub.c:4562
put_pipe_info fs/pipe.c:711 [inline]
pipe_release+0x2bf/0x320 fs/pipe.c:734
__fput+0x286/0x9f0 fs/file_table.c:317
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
The buggy address belongs to the object at ffff88807bc04800
which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 168 bytes inside of
512-byte region [ffff88807bc04800, ffff88807bc04a00)
The buggy address belongs to the page:
page:ffffea0001ef0100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bc04
head:ffffea0001ef0100 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888010c42dc0
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3609, ts 50514720858, free_ts 25116018184
prep_new_page mm/page_alloc.c:2434 [inline]
get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
__alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
alloc_slab_page mm/slub.c:1799 [inline]
allocate_slab+0x27f/0x3c0 mm/slub.c:1944
new_slab mm/slub.c:2004 [inline]
___slab_alloc+0xbe1/0x12b0 mm/slub.c:3018
__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
slab_alloc_node mm/slub.c:3196 [inline]
slab_alloc mm/slub.c:3238 [inline]
kmem_cache_alloc_trace+0x2f8/0x3d0 mm/slub.c:3255
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
alloc_pipe_info+0x105/0x590 fs/pipe.c:790
get_pipe_inode fs/pipe.c:881 [inline]
create_pipe_files+0x8d/0x880 fs/pipe.c:913
__do_pipe_flags fs/pipe.c:962 [inline]
do_pipe2+0x96/0x1b0 fs/pipe.c:1010
__do_sys_pipe2 fs/pipe.c:1028 [inline]
__se_sys_pipe2 fs/pipe.c:1026 [inline]
__x64_sys_pipe2+0x50/0x70 fs/pipe.c:1026
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1352 [inline]
free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
free_unref_page_prepare mm/page_alloc.c:3325 [inline]
free_unref_page+0x19/0x690 mm/page_alloc.c:3404
__unfreeze_partials+0x320/0x340 mm/slub.c:2536
qlink_free mm/kasan/quarantine.c:157 [inline]
qlist_free_all+0x6d/0x160 mm/kasan/quarantine.c:176
kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283
__kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446
kasan_slab_alloc include/linux/kasan.h:260 [inline]
slab_post_alloc_hook mm/slab.h:732 [inline]
slab_alloc_node mm/slub.c:3230 [inline]
slab_alloc mm/slub.c:3238 [inline]
kmem_cache_alloc_trace+0x258/0x3d0 mm/slub.c:3255
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
tomoyo_init_log+0xc6a/0x1ee0 security/tomoyo/audit.c:264
tomoyo_supervisor+0x34d/0xf00 security/tomoyo/common.c:2097
tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
tomoyo_env_perm+0x17f/0x1f0 security/tomoyo/environ.c:63
tomoyo_environ security/tomoyo/domain.c:672 [inline]
tomoyo_find_next_domain+0x13ce/0x1f80 security/tomoyo/domain.c:879
tomoyo_bprm_check_security security/tomoyo/tomoyo.c:101 [inline]
tomoyo_bprm_check_security+0x121/0x1a0 security/tomoyo/tomoyo.c:91
security_bprm_check+0x45/0xa0 security/security.c:866
search_binary_handler fs/exec.c:1715 [inline]
exec_binprm fs/exec.c:1768 [inline]
bprm_execve fs/exec.c:1837 [inline]
bprm_execve+0x732/0x19b0 fs/exec.c:1799
do_execveat_common+0x5e3/0x780 fs/exec.c:1926
do_execve fs/exec.c:1994 [inline]
__do_sys_execve fs/exec.c:2070 [inline]
__se_sys_execve fs/exec.c:2065 [inline]
__x64_sys_execve+0x8f/0xc0 fs/exec.c:2065
Memory state around the buggy address:
ffff88807bc04780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88807bc04800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807bc04880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807bc04900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807bc04980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email protected].
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches
#syz test: [email protected]:siddhpant/linux.git post_one_notification
#syz test: https://github.com/siddhpant/linux.git post_one_notification
Hello,
syzbot tried to test the proposed patch but the build/boot failed:
failed to checkout kernel repo [email protected]:siddhpant/linux.git/post_one_notification: failed to run ["git" "fetch" "--force" "219a8dc7158a7de03b74c244ef07dcd062b9b3f7" "post_one_notification"]: exit status 128
Host key verification failed.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
Tested on:
commit: [unknown
git tree: [email protected]:siddhpant/linux.git post_one_notification
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler:
Note: no patches were applied.
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: [email protected]
Tested on:
commit: 778e6ace kernel/watch_queue: Make pipe NULL while clea..
git tree: https://github.com/siddhpant/linux.git post_one_notification
console output: https://syzkaller.appspot.com/x/log.txt?x=13049d52080000
kernel config: https://syzkaller.appspot.com/x/.config?x=95c061eee05f8e15
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: [email protected]
Tested on:
commit: 551acdc3 Merge tag 'net-5.17-final' of git://git.kerne..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=133a814a080000
kernel config: https://syzkaller.appspot.com/x/.config?x=e006319d4b3bc11a
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=13b8c83c080000
Note: testing is done by a robot and is best-effort only.
#syz test: https://github.com/siddhpant/linux.git post_one_notification
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: [email protected]
Tested on:
commit: fa4c07d9 kernel/watch_queue: Make pipe NULL while clea..
git tree: https://github.com/siddhpant/linux.git post_one_notification
console output: https://syzkaller.appspot.com/x/log.txt?x=17f5cf52080000
kernel config: https://syzkaller.appspot.com/x/.config?x=95c061eee05f8e15
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: [email protected]
Tested on:
commit: 16007670 kernel/watch_queue: Make pipe NULL while clea..
git tree: https://github.com/siddhpant/linux.git post_one_notification
console output: https://syzkaller.appspot.com/x/log.txt?x=11a6eade080000
kernel config: https://syzkaller.appspot.com/x/.config?x=95c061eee05f8e15
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.
#syz test: https://github.com/siddhpant/linux.git post_one_notification
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: [email protected]
Tested on:
commit: 3d7cb6b0 Linux 5.19
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=14066d7a080000
kernel config: https://syzkaller.appspot.com/x/.config?x=70dd99d568a89e0
dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.
On Mon, Aug 01, 2022 at 03:54:09AM -0700, syzbot wrote:
> Hello,
>
> syzbot has tested the proposed patch and the reproducer did not trigger any issue:
>
> Reported-and-tested-by: [email protected]
>
> Tested on:
>
> commit: 3d7cb6b0 Linux 5.19
> git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> console output: https://syzkaller.appspot.com/x/log.txt?x=14066d7a080000
> kernel config: https://syzkaller.appspot.com/x/.config?x=70dd99d568a89e0
> dashboard link: https://syzkaller.appspot.com/bug?extid=c70d87ac1d001f29a058
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
>
> Note: no patches were applied.
> Note: testing is done by a robot and is best-effort only.
It appears this was already fixed, so no need for any more activity on this bug:
#syz fix: watchqueue: make sure to serialize 'wqueue->defunct' properly
- Eric
On Wed, 03 Aug 2022 03:57:19 +0530 Eric Biggers <[email protected]> wrote:
> It appears this was already fixed, so no need for any more activity on this bug:
>
> #syz fix: watchqueue: make sure to serialize 'wqueue->defunct' properly
>
> - Eric
It doesn't address the dangling pointer remaining in the watch_queue,
which was the root cause of this crash. The use-after-free happened
because the pipe was freed but a dangling pointer of it remained in
a watch_queue, and an attempt to dereference it was there.
Thanks,
Siddh
On Wed, Aug 03, 2022 at 09:34:10AM +0530, Siddh Raman Pant wrote:
> On Wed, 03 Aug 2022 03:57:19 +0530 Eric Biggers <[email protected]> wrote:
> > It appears this was already fixed, so no need for any more activity on this bug:
> >
> > #syz fix: watchqueue: make sure to serialize 'wqueue->defunct' properly
> >
> > - Eric
>
> It doesn't address the dangling pointer remaining in the watch_queue,
> which was the root cause of this crash. The use-after-free happened
> because the pipe was freed but a dangling pointer of it remained in
> a watch_queue, and an attempt to dereference it was there.
>
I don't think that's true; the pointer doesn't get dereferenced after
watch_queue::defunct is set. See my message on the other thread where I
explained this: https://lore.kernel.org/lkml/[email protected]
Of course, if you actually have a reproducer, or a KASAN report, or anything at
all that shows there is still a problem, then please post it.
- Eric
On Wed, 03 Aug 2022 09:39:34 +0530 Eric Biggers <[email protected]> wrote:
> I don't think that's true; the pointer doesn't get dereferenced after
> watch_queue::defunct is set. See my message on the other thread where I
> explained this: https://lore.kernel.org/lkml/[email protected]
>
> Of course, if you actually have a reproducer, or a KASAN report, or anything at
> all that shows there is still a problem, then please post it.
>
> - Eric
Replying to the other thread.
Thanks,
Siddh