Hello,
syzbot found the following issue on:
HEAD commit: f67653019430 Linux 5.15.118
git tree: linux-5.15.y
console output:
https://syzkaller.appspot.com/x/log.txt?x=1746a21f280000
kernel config:
https://syzkaller.appspot.com/x/.config?x=717fa62bb7f0fe9
dashboard link:
https://syzkaller.appspot.com/bug?extid=c7d9b2e7d8efb0044656
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image:
https://storage.googleapis.com/syzbot-assets/d21188fbe046/disk-f6765301.raw.xz
vmlinux:
https://storage.googleapis.com/syzbot-assets/f0c688e23e63/vmlinux-f6765301.xz
kernel image:
https://storage.googleapis.com/syzbot-assets/eca85b3bf72c/bzImage-f6765301.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by:
syzbot+c7d9b2...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x74/0x1ff0 kernel/locking/lockdep.c:4881
Read of size 8 at addr ffff888077a18a28 by task kworker/u4:21/7368
CPU: 0 PID: 7368 Comm: kworker/u4:21 Not tainted 5.15.118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: btrfs-delalloc btrfs_work_helper
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
print_address_description+0x63/0x3b0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:434 [inline]
kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
__lock_acquire+0x74/0x1ff0 kernel/locking/lockdep.c:4881
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4026
async_cow_free+0x4d/0x350 fs/btrfs/inode.c:1384
run_ordered_work fs/btrfs/async-thread.c:298 [inline]
btrfs_work_helper+0x8ed/0xba0 fs/btrfs/async-thread.c:335
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2307
worker_thread+0xaca/0x1280 kernel/workqueue.c:2454
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
Allocated by task 2:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
__kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
slab_alloc_node mm/slub.c:3220 [inline]
kmem_cache_alloc_node+0x121/0x2c0 mm/slub.c:3256
alloc_task_struct_node kernel/fork.c:171 [inline]
dup_task_struct+0x57/0xb60 kernel/fork.c:886
copy_process+0x5eb/0x3ef0 kernel/fork.c:2030
kernel_clone+0x210/0x960 kernel/fork.c:2601
kernel_thread+0x168/0x1e0 kernel/fork.c:2653
create_kthread kernel/kthread.c:342 [inline]
kthreadd+0x57d/0x740 kernel/kthread.c:686
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
Freed by task 3556:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:1705 [inline]
slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
slab_free mm/slub.c:3499 [inline]
kmem_cache_free+0x91/0x1f0 mm/slub.c:3515
rcu_do_batch kernel/rcu/tree.c:2510 [inline]
rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2750
__do_softirq+0x3b3/0x93a kernel/softirq.c:558
Last potentially related work creation:
kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
__call_rcu kernel/rcu/tree.c:2994 [inline]
call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3074
context_switch kernel/sched/core.c:5029 [inline]
__schedule+0x12cc/0x4590 kernel/sched/core.c:6372
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6776
irqentry_exit+0x53/0x80 kernel/entry/common.c:426
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
Second to last potentially related work creation:
kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
__call_rcu kernel/rcu/tree.c:2994 [inline]
call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3074
context_switch kernel/sched/core.c:5029 [inline]
__schedule+0x12cc/0x4590 kernel/sched/core.c:6372
schedule+0x11b/0x1f0 kernel/sched/core.c:6455
schedule_timeout+0xac/0x300 kernel/time/timer.c:1860
unix_wait_for_peer+0x24b/0x330 net/unix/af_unix.c:1315
unix_dgram_sendmsg+0x1441/0x2090 net/unix/af_unix.c:1913
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2412
___sys_sendmsg+0x252/0x2e0 net/socket.c:2466
__sys_sendmmsg+0x2bf/0x560 net/socket.c:2552
__do_sys_sendmmsg net/socket.c:2581 [inline]
__se_sys_sendmmsg net/socket.c:2578 [inline]
__x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2578
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
The buggy address belongs to the object at ffff888077a18000
which belongs to the cache task_struct of size 7360
The buggy address is located 2600 bytes inside of
7360-byte region [ffff888077a18000, ffff888077a19cc0)
The buggy address belongs to the page:
page:ffffea0001de8600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x77a18
head:ffffea0001de8600 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88801e14d581
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000200000001 ffff888140006280
raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88801e14d581
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 548, ts 398647068275, free_ts 396339849129
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
__alloc_pages+0x272/0x700 mm/page_alloc.c:5421
alloc_slab_page mm/slub.c:1775 [inline]
allocate_slab mm/slub.c:1912 [inline]
new_slab+0xbb/0x4b0 mm/slub.c:1975
___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
__slab_alloc mm/slub.c:3095 [inline]
slab_alloc_node mm/slub.c:3186 [inline]
kmem_cache_alloc_node+0x1ba/0x2c0 mm/slub.c:3256
alloc_task_struct_node kernel/fork.c:171 [inline]
dup_task_struct+0x57/0xb60 kernel/fork.c:886
copy_process+0x5eb/0x3ef0 kernel/fork.c:2030
kernel_clone+0x210/0x960 kernel/fork.c:2601
kernel_thread+0x168/0x1e0 kernel/fork.c:2653
call_usermodehelper_exec_sync kernel/umh.c:135 [inline]
call_usermodehelper_exec_work+0x93/0x220 kernel/umh.c:166
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2307
worker_thread+0xaca/0x1280 kernel/workqueue.c:2454
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1340 [inline]
free_pcp_prepare mm/page_alloc.c:1391 [inline]
free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
free_slab mm/slub.c:2015 [inline]
discard_slab mm/slub.c:2021 [inline]
__unfreeze_partials+0x1b7/0x210 mm/slub.c:2507
put_cpu_partial+0x132/0x1a0 mm/slub.c:2587
do_slab_free mm/slub.c:3487 [inline]
___cache_free+0xe3/0x100 mm/slub.c:3506
qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
__kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
slab_alloc_node mm/slub.c:3220 [inline]
kmem_cache_alloc_node+0x121/0x2c0 mm/slub.c:3256
__alloc_skb+0xdd/0x590 net/core/skbuff.c:415
alloc_skb_fclone include/linux/skbuff.h:1217 [inline]
sk_stream_alloc_skb+0x1fc/0xad0 net/ipv4/tcp.c:887
tcp_sendmsg_locked+0xe0c/0x3ab0 net/ipv4/tcp.c:1310
tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1462
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
sock_write_iter+0x39b/0x530 net/socket.c:1060
call_write_iter include/linux/fs.h:2103 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0xacf/0xe50 fs/read_write.c:594
Memory state around the buggy address:
ffff888077a18900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888077a18980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888077a18a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888077a18a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888077a18b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
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