syzbot


WARNING in do_loopback

Status: auto-obsoleted due to no activity on 2023/11/01 08:13
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+e866270d4721acf901c4@syzkaller.appspotmail.com
First crash: 292d, last: 292d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in do_loopback 2 7d13h 82d 0/3 upstream: reported on 2024/02/29 12:54
linux-5.15 WARNING in do_loopback 1 25d 25d 0/3 upstream: reported on 2024/04/26 13:38
upstream WARNING in do_loopback (2) fs 5 4d14h 42d 0/26 moderation: reported on 2024/04/09 04:36

Sample crash report:
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff8880868611f0, owner = 0x0, curr 0xffff88807dab8000, list empty
WARNING: CPU: 1 PID: 14589 at kernel/locking/rwsem.c:1370 __up_write kernel/locking/rwsem.c:1369 [inline]
WARNING: CPU: 1 PID: 14589 at kernel/locking/rwsem.c:1370 up_write+0x4f4/0x580 kernel/locking/rwsem.c:1626
Modules linked in:
CPU: 1 PID: 14589 Comm: syz-executor.5 Not tainted 6.5.0-rc4-syzkaller-00041-gec351c8f2e62 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
RIP: 0010:__up_write kernel/locking/rwsem.c:1369 [inline]
RIP: 0010:up_write+0x4f4/0x580 kernel/locking/rwsem.c:1626
Code: 48 c7 c7 00 83 0a 8b 48 c7 c6 40 85 0a 8b 48 8b 54 24 28 48 8b 4c 24 18 4d 89 e0 4c 8b 4c 24 30 53 e8 30 59 e8 ff 48 83 c4 08 <0f> 0b e9 75 fd ff ff 48 c7 c1 48 96 98 8e 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc90003a3fca0 EFLAGS: 00010296
RAX: fb8ef5ceca9d6a00 RBX: ffffffff8b0a83e0 RCX: ffff88807dab8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003a3fd70 R08: ffffffff8152c3a2 R09: 1ffff92000747f0c
R10: dffffc0000000000 R11: fffff52000747f0d R12: 0000000000000000
R13: ffff8880868611f0 R14: 1ffff92000747f9c R15: dffffc0000000000
FS:  00007fb7aeca46c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a84c1d000 CR3: 000000007b9f5000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:776 [inline]
 unlock_mount fs/namespace.c:2508 [inline]
 do_loopback+0x4ab/0x510 fs/namespace.c:2642
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb7ade7cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb7aeca40c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb7adf9c050 RCX: 00007fb7ade7cae9
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000020000040
RBP: 00007fb7adec847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fb7adf9c050 R15: 00007fff5cde7108
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/03 08:13 upstream ec351c8f2e62 39a91c18 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in do_loopback
* Struck through repros no longer work on HEAD.