BUG: corrupted list in prepare_to_wait_event

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 017d67e9 ANDROID: CC_FLAGS_CFI add -fno-sanitize-blacklist
git tree: android-5.4
console output: https://syzkaller.appspot.com/x/log.txt?x=12b7f7ede00000
kernel config: https://syzkaller.appspot.com/x/.config?x=3f89e7b19e996a7b
dashboard link: https://syzkaller.appspot.com/bug?extid=203dab0973ed2614b955
compiler: Android (6032204 based on r370808) clang version 10.0.1 (https://android.googlesource.com/toolchain/llvm-project 6e765c10313d15c02ab29977a82938f66742c3a9)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+203dab...@syzkaller.appspotmail.com

list_del corruption. prev->next should be ffff8881a0c1fb98, but was 0000000000000000
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:53!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 16887 Comm: syz-executor.3 Tainted: G W 5.4.24-syzkaller-00161-g017d67e9a8b3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_del_entry_valid+0xe6/0x100 lib/list_debug.c:51
Code: a7 60 30 ff 0f 0b 48 c7 c7 a4 6b 4f 84 4c 89 f6 31 c0 e8 94 60 30 ff 0f 0b 48 c7 c7 dc 6b 4f 84 4c 89 f6 31 c0 e8 81 60 30 ff <0f> 0b 48 c7 c7 1a 6c 4f 84 4c 89 f6 31 c0 e8 6e 60 30 ff 0f 0b 90
RSP: 0018:ffff8881a0c1f9f0 EFLAGS: 00010046
RAX: 0000000000000054 RBX: ffff8881cc805168 RCX: a6c4804c30946c00
RDX: ffffc9000277f000 RSI: 0000000000001206 RDI: 0000000000001207
RBP: ffff8881a0c1fa10 R08: ffffffff812d0c80 R09: ffffed103b743e92
R10: ffffed103b743e92 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8881a0c1fb98 R14: ffff8881a0c1fb98 R15: ffff8881cc805168
FS: 00007f2cf3e7f700(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000b70004 CR3: 00000001d0058005 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
__list_del_entry include/linux/list.h:131 [inline]
list_del_init include/linux/list.h:190 [inline]
prepare_to_wait_event+0x2d7/0x530 kernel/sched/wait.c:277
uhid_char_read+0x24f/0x6e0 drivers/hid/uhid.c:669
do_loop_readv_writev fs/read_write.c:717 [inline]
do_iter_read+0x4a2/0x5b0 fs/read_write.c:938
vfs_readv fs/read_write.c:1000 [inline]
do_readv+0x216/0x400 fs/read_write.c:1037
__do_sys_readv fs/read_write.c:1128 [inline]
__se_sys_readv fs/read_write.c:1125 [inline]
__x64_sys_readv+0x7d/0x90 fs/read_write.c:1125
do_syscall_64+0xc0/0x100 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c479
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2cf3e7ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
RAX: ffffffffffffffda RBX: 00007f2cf3e7f6d4 RCX: 000000000045c479
RDX: 0000000000000002 RSI: 0000000020001680 RDI: 0000000000000003
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000887 R14: 00000000004cada6 R15: 000000000076bf2c
Modules linked in:
---[ end trace 84543ab2270f76c6 ]---
RIP: 0010:__list_del_entry_valid+0xe6/0x100 lib/list_debug.c:51
Code: a7 60 30 ff 0f 0b 48 c7 c7 a4 6b 4f 84 4c 89 f6 31 c0 e8 94 60 30 ff 0f 0b 48 c7 c7 dc 6b 4f 84 4c 89 f6 31 c0 e8 81 60 30 ff <0f> 0b 48 c7 c7 1a 6c 4f 84 4c 89 f6 31 c0 e8 6e 60 30 ff 0f 0b 90
RSP: 0018:ffff8881a0c1f9f0 EFLAGS: 00010046
RAX: 0000000000000054 RBX: ffff8881cc805168 RCX: a6c4804c30946c00
RDX: ffffc9000277f000 RSI: 0000000000001206 RDI: 0000000000001207
RBP: ffff8881a0c1fa10 R08: ffffffff812d0c80 R09: ffffed103b743e92
R10: ffffed103b743e92 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8881a0c1fb98 R14: ffff8881a0c1fb98 R15: ffff8881cc805168
FS: 00007f2cf3e7f700(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000b70004 CR3: 00000001d0058005 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600


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[syzbot]

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