general protection fault in css_free_rwork_fn

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e3d35712 Add linux-next specific files for 20210423
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=172014b9d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=e370221d7500b26a
dashboard link: https://syzkaller.appspot.com/bug?extid=dad8fc4de35dddc860f8
CC: [and...@kernel.org a...@kernel.org b...@vger.kernel.org cgr...@vger.kernel.org chri...@brauner.io dan...@iogearbox.net han...@cmpxchg.org john.fa...@gmail.com ka...@fb.com kps...@kernel.org linux-...@vger.kernel.org lize...@bytedance.com net...@vger.kernel.org songliu...@fb.com t...@kernel.org y...@fb.com]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dad8fc...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc00000000cd: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000668-0x000000000000066f]
CPU: 0 PID: 4827 Comm: kworker/0:3 Not tainted 5.12.0-rc8-next-20210423-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: cgroup_destroy css_free_rwork_fn
RIP: 0010:css_free_rwork_fn+0xe2/0x10f0 kernel/cgroup/cgroup.c:4928
Code: ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 64 04 00 00 48 8d 7d 20 8b 5b a0 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9d 0d 00 00 4c 89 f7 ff 55 20 48 c7 c7 e0 bd fb
RSP: 0018:ffffc9000b8e7cc8 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00000000000000cd RSI: ffffffff816e6972 RDI: 000000000000066e
RBP: 000000000000064e R08: 0000000000000001 R09: ffffffff90207957
R10: 0000000000000001 R11: 0000000000084087 R12: 00000870ffffea00
R13: ffff8880290a0000 R14: ffff888014528000 R15: ffff8880b9c34a80
FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe2b482f6b8 CR3: 0000000024405000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
kthread+0x3b1/0x4a0 kernel/kthread.c:313
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Modules linked in:
---[ end trace ca06c9e83614f55b ]---
RIP: 0010:css_free_rwork_fn+0xe2/0x10f0 kernel/cgroup/cgroup.c:4928
Code: ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 64 04 00 00 48 8d 7d 20 8b 5b a0 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9d 0d 00 00 4c 89 f7 ff 55 20 48 c7 c7 e0 bd fb
RSP: 0018:ffffc9000b8e7cc8 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00000000000000cd RSI: ffffffff816e6972 RDI: 000000000000066e
RBP: 000000000000064e R08: 0000000000000001 R09: ffffffff90207957
R10: 0000000000000001 R11: 0000000000084087 R12: 00000870ffffea00
R13: ffff8880290a0000 R14: ffff888014528000 R15: ffff8880b9c34a80
FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff17803f028 CR3: 0000000013177000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.