syzbot


WARNING in chown_common (3)

Status: upstream: reported on 2026/01/05 12:35
Reported-by: syzbot+ac66e799fe4c2c027fc4@syzkaller.appspotmail.com
First crash: 12d, last: 5d00h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in chown_common -1 14 532d 647d 0/3 auto-obsoleted due to no activity on 2024/11/11 04:47
linux-6.1 WARNING in chown_common (2) -1 6 125d 227d 0/3 auto-obsoleted due to no activity on 2025/12/23 04:01
upstream WARNING in chown_common gfs2 -1 C 191 3d02h 97d 0/29 upstream: reported C repro on 2025/10/12 05:45

Sample crash report:
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff888072781508, owner = 0x0, curr 0xffff88802cffbb80, list empty
WARNING: CPU: 1 PID: 4719 at kernel/locking/rwsem.c:1372 __up_write kernel/locking/rwsem.c:1371 [inline]
WARNING: CPU: 1 PID: 4719 at kernel/locking/rwsem.c:1372 up_write+0x3a1/0x420 kernel/locking/rwsem.c:1626
Modules linked in:
CPU: 1 PID: 4719 Comm: syz.2.84 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__up_write kernel/locking/rwsem.c:1371 [inline]
RIP: 0010:up_write+0x3a1/0x420 kernel/locking/rwsem.c:1626
Code: 44 d0 48 c7 c7 80 f9 6b 8a 48 c7 c6 c0 fb 6b 8a 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 b3 6d ea ff 48 83 c4 08 <0f> 0b e9 6b fd ff ff 48 c7 c1 28 59 ff 8d 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc900063f7c70 EFLAGS: 00010292
RAX: 4c4daeeeafe1da00 RBX: ffff888072781508 RCX: 0000000000080000
RDX: ffffc9000e49a000 RSI: 000000000000d212 RDI: 000000000000d213
RBP: dffffc0000000000 R08: dffffc0000000000 R09: fffff52000c7ef1d
R10: fffff52000c7ef1d R11: 1ffff92000c7ef1c R12: 0000000000000000
R13: ffff888072781560 R14: ffff888072781508 R15: 1ffff1100e4f02a2
FS:  00007f8ac85d56c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 000000002ef9a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:763 [inline]
 chown_common+0x490/0x620 fs/open.c:738
 do_fchownat+0x164/0x270 fs/open.c:767
 __do_sys_lchown fs/open.c:792 [inline]
 __se_sys_lchown fs/open.c:790 [inline]
 __x64_sys_lchown+0x81/0x90 fs/open.c:790
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8aca38f749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8ac85d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000005e
RAX: ffffffffffffffda RBX: 00007f8aca5e6090 RCX: 00007f8aca38f749
RDX: 00000000ffffffff RSI: 00000000ffffffff RDI: 0000200000002700
RBP: 00007f8aca413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8aca5e6128 R14: 00007f8aca5e6090 R15: 00007ffc212104e8
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/12 12:22 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in chown_common
2026/01/05 12:34 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in chown_common
* Struck through repros no longer work on HEAD.