syzbot


WARNING in do_loopback (2)

Status: moderation: reported on 2024/04/09 04:36
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+54b23838c478d1b401a1@syzkaller.appspotmail.com
First crash: 25d, last: 2d02h
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in do_loopback 1 61d 61d 0/3 upstream: reported on 2024/02/29 12:54
linux-5.15 WARNING in do_loopback 1 4d05h 4d05h 0/3 upstream: reported on 2024/04/26 13:38
upstream WARNING in do_loopback fs 1 271d 267d 0/26 auto-obsoleted due to no activity on 2023/11/01 08:13

Sample crash report:
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff88805b9f8a90, owner = 0x0, curr 0xffff8880635ada00, list empty
WARNING: CPU: 1 PID: 8897 at kernel/locking/rwsem.c:1370 __up_write kernel/locking/rwsem.c:1369 [inline]
WARNING: CPU: 1 PID: 8897 at kernel/locking/rwsem.c:1370 up_write+0x502/0x590 kernel/locking/rwsem.c:1632
Modules linked in:
CPU: 1 PID: 8897 Comm: syz-executor.2 Not tainted 6.9.0-rc4-syzkaller-00329-g48cf398f15fc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:__up_write kernel/locking/rwsem.c:1369 [inline]
RIP: 0010:up_write+0x502/0x590 kernel/locking/rwsem.c:1632
Code: c7 c7 20 ac ca 8b 48 c7 c6 a0 ae ca 8b 48 8b 54 24 28 48 8b 4c 24 18 4d 89 e0 4c 8b 4c 24 30 53 e8 b3 b6 e6 ff 48 83 c4 08 90 <0f> 0b 90 90 e9 6a fd ff ff 48 c7 c1 00 16 a9 8f 80 e1 07 80 c1 03
RSP: 0018:ffffc9000956fc80 EFLAGS: 00010292
RAX: 7fb5c375d05b6100 RBX: ffffffff8bcaad00 RCX: 0000000000040000
RDX: ffffc9000bfe4000 RSI: 00000000000103c4 RDI: 00000000000103c5
RBP: ffffc9000956fd50 R08: ffffffff81588072 R09: fffffbfff1c39b48
R10: dffffc0000000000 R11: fffffbfff1c39b48 R12: 0000000000000000
R13: ffff88805b9f8a90 R14: 1ffff920012adf98 R15: dffffc0000000000
FS:  00007f974241d6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c000fbc000 CR3: 000000002bc0e000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:800 [inline]
 unlock_mount fs/namespace.c:2514 [inline]
 do_loopback+0x4ad/0x520 fs/namespace.c:2648
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f974167dea9
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:00007f974241d0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f97417ac050 RCX: 00007f974167dea9
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 00000000200002c0
RBP: 00007f97416ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000101091 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f97417ac050 R15: 00007fffc6ee7c78
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/22 08:36 upstream 48cf398f15fc af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in do_loopback
2024/04/05 04:25 upstream fe46a7dd189e 0ee3535e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in do_loopback
2024/04/28 16:30 linux-next bb7a2467e6be 07b455f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in do_loopback
* Struck through repros no longer work on HEAD.