syzbot


WARNING in futex_requeue

Status: fixed on 2021/11/10 00:50
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+4d1bd0725ef09168e1a0@syzkaller.appspotmail.com
Fix commit: 4f07ec0d76f2 futex: Prevent inconsistent state and exit race
First crash: 966d, last: 962d
Discussions (2)
Title Replies (including bot) Last reply
[patch 1/3] futex: Prevent inconsistent state and exit race 3 (3) 2021/09/02 20:14
[syzbot] WARNING in futex_requeue 1 (2) 2021/09/01 19:52

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 25500 at kernel/futex.c:2259 futex_requeue+0x1467/0x2d50 kernel/futex.c:2259
Modules linked in:
CPU: 1 PID: 25500 Comm: syz-executor.0 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:futex_requeue+0x1467/0x2d50 kernel/futex.c:2259
Code: 02 00 00 4c 8d 84 24 90 02 00 00 e8 63 6a 00 00 41 89 c7 31 ff 89 c6 e8 e7 4e 0c 00 45 85 ff 0f 84 d8 13 00 00 e8 c9 4a 0c 00 <0f> 0b eb 05 e8 c0 4a 0c 00 4c 89 fb 89 df 48 c7 c6 b0 7b 93 8c e8
RSP: 0018:ffffc90009b47640 EFLAGS: 00010293
RAX: ffffffff81749f17 RBX: 0000000000001cf3 RCX: ffff888012dfd580
RDX: 0000000000000000 RSI: 00000000fffffffd RDI: 0000000000000000
RBP: ffffc90009b47948 R08: ffffffff81749f09 R09: fffffbfff1bb8166
R10: fffffbfff1bb8166 R11: 0000000000000000 R12: 0000000020048000
R13: dffffc0000000000 R14: 0000000000000000 R15: 00000000fffffffd
FS:  00007ff158e3f700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000056c030 CR3: 0000000018186000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_futex+0x1b97/0x32c0
 __do_sys_futex kernel/futex.c:4009 [inline]
 __se_sys_futex+0x11c/0x4d0 kernel/futex.c:3990
 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+0x44/0xae
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff158e3f188 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665f9
RDX: 0000000000000001 RSI: 000000000000000c RDI: 000000002000cffc
RBP: 00000000004bfcc4 R08: 0000000020048000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 00007ffcdb88960f R14: 00007ff158e3f300 R15: 0000000000022000

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/09/06 01:49 upstream 0319b848b155 d236a457 .config console log report syz ci-upstream-kasan-gce-smack-root WARNING in futex_requeue
2021/09/05 00:32 upstream f1583cb1be35 d236a457 .config console log report syz ci-upstream-kasan-gce-smack-root WARNING in futex_requeue
2021/09/02 21:14 upstream 4ac6d90867a4 15cea0a3 .config console log report syz ci-upstream-kasan-gce-smack-root WARNING in futex_requeue
2021/09/01 12:41 upstream b91db6a0b52e 7eb7e152 .config console log report syz ci-upstream-kasan-gce-smack-root WARNING in futex_requeue
* Struck through repros no longer work on HEAD.