Re: [syzbot] [vfs?] [ntfs3?] [tmpfs?] WARNING in walk_component

syzbot
2023-01-06T16:15:42Z

syzbot has found a reproducer for the following issue on:

HEAD commit: 1f5abbd77e2c Merge tag 'thermal-6.2-rc3' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=113cc806480000
kernel config: https://syzkaller.appspot.com/x/.config?x=46221e8203c7aca6
dashboard link: https://syzkaller.appspot.com/bug?extid=eba014ac93ef29f83dc8
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17f5d83a480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1727f4b4480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6c5b2e8c2c94/disk-1f5abbd7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8956b2eee8db/vmlinux-1f5abbd7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c3464b3b12f5/bzImage-1f5abbd7.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6acfd5ce1186/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+eba014ac93ef29f83dc8@syzkaller.appspotmail.com

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DEBUG_RWSEMS_WARN_ON(!is_rwsem_reader_owned(sem)): count = 0x0, magic = 0xffff8880708871d0, owner = 0x0, curr 0xffff8880279e1d40, list empty
WARNING: CPU: 1 PID: 5194 at kernel/locking/rwsem.c:1336 __up_read+0x5c0/0x720 kernel/locking/rwsem.c:1336
Modules linked in:
CPU: 1 PID: 5194 Comm: syz-executor234 Not tainted 6.2.0-rc2-syzkaller-00203-g1f5abbd77e2c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:__up_read+0x5c0/0x720 kernel/locking/rwsem.c:1336
Code: 03 80 3c 02 00 0f 85 35 01 00 00 49 8b 17 4d 89 f1 4c 89 e9 48 c7 c6 80 44 4c 8a ff 34 24 48 c7 c7 c0 41 4c 8a e8 70 b8 5c 08 <0f> 0b 5e e9 38 fb ff ff 48 89 df e8 e0 8a 6c 00 e9 b2 fa ff ff 48
RSP: 0018:ffffc90003f4fb58 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff8e730c28 RCX: 0000000000000000
RDX: ffff8880279e1d40 RSI: ffffffff8166721c RDI: fffff520007e9f5d
RBP: ffff8880708871d8 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000000 R12: 1ffff920007e9f6f
R13: ffff8880708871d0 R14: ffff8880279e1d40 R15: ffff8880708871d0
FS: 00007f022ae3c700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f02330f3120 CR3: 000000001d72a000 CR4: 0000000000350ee0
Call Trace:
<TASK>
inode_unlock_shared include/linux/fs.h:771 [inline]
lookup_slow fs/namei.c:1703 [inline]
walk_component+0x34a/0x5a0 fs/namei.c:1993
lookup_last fs/namei.c:2450 [inline]
path_lookupat+0x1ba/0x840 fs/namei.c:2474
filename_lookup+0x1d2/0x590 fs/namei.c:2503
user_path_at_empty+0x46/0x60 fs/namei.c:2876
user_path_at include/linux/namei.h:57 [inline]
__do_sys_chdir fs/open.c:514 [inline]
__se_sys_chdir fs/open.c:508 [inline]
__x64_sys_chdir+0xbb/0x240 fs/open.c:508
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f02330b1a19
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f022ae3c2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
RAX: ffffffffffffffda RBX: 0000000000000029 RCX: 00007f02330b1a19
RDX: 00007f02330b1a19 RSI: ffffffffffffffb8 RDI: 0000000020000380
RBP: 00007f0233155798 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0233155790
R13: 00007f023315579c R14: 6573726168636f69 R15: 0030656c69662f2e