syzbot


possible deadlock in open_xa_dir

Status: auto-obsoleted due to no activity on 2023/08/23 09:03
Reported-by: syzbot+fc8e28299535f14bf75b@syzkaller.appspotmail.com
First crash: 436d, last: 422d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in open_xa_dir (2) origin:upstream C 85 11d 81d 0/3 upstream: reported C repro on 2024/03/31 06:40
upstream possible deadlock in open_xa_dir reiserfs C done done 7667 142d 537d 0/27 auto-obsoleted due to no activity on 2024/04/09 20:57
linux-6.1 possible deadlock in open_xa_dir 3 430d 439d 0/3 auto-obsoleted due to no activity on 2023/08/15 19:04
linux-4.19 possible deadlock in open_xa_dir reiserfs C error 3 533d 539d 0/1 upstream: reported C repro on 2022/12/29 15:01
linux-5.15 possible deadlock in open_xa_dir (2) origin:upstream C 61 8d14h 79d 0/3 upstream: reported C repro on 2024/04/02 08:22

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.15.106-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.3/14767 is trying to acquire lock:
ffff8880836c9d60 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
ffff8880836c9d60 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: open_xa_root fs/reiserfs/xattr.c:127 [inline]
ffff8880836c9d60 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: open_xa_dir+0x132/0x610 fs/reiserfs/xattr.c:152

but task is already holding lock:
ffff88807a90b090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x5b/0xd0 fs/reiserfs/lock.c:78

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sbi->lock){+.+.}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       reiserfs_write_lock+0x76/0xd0 fs/reiserfs/lock.c:27
       reiserfs_mkdir+0x31d/0x8f0 fs/reiserfs/namei.c:831
       xattr_mkdir fs/reiserfs/xattr.c:76 [inline]
       open_xa_root fs/reiserfs/xattr.c:136 [inline]
       open_xa_dir+0x2c9/0x610 fs/reiserfs/xattr.c:152
       xattr_lookup+0x24/0x280 fs/reiserfs/xattr.c:395
       reiserfs_xattr_set_handle+0x100/0x10b0 fs/reiserfs/xattr.c:540
       reiserfs_xattr_set+0x44e/0x570 fs/reiserfs/xattr.c:640
       __vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
       __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
       vfs_setxattr+0x21d/0x420 fs/xattr.c:303
       do_setxattr fs/xattr.c:588 [inline]
       setxattr+0x27e/0x2e0 fs/xattr.c:611
       __do_sys_fsetxattr fs/xattr.c:667 [inline]
       __se_sys_fsetxattr+0x194/0x210 fs/xattr.c:656
       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+0x61/0xcb

-> #0 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       down_write_nested+0xa0/0x180 kernel/locking/rwsem.c:1657
       inode_lock_nested include/linux/fs.h:822 [inline]
       open_xa_root fs/reiserfs/xattr.c:127 [inline]
       open_xa_dir+0x132/0x610 fs/reiserfs/xattr.c:152
       reiserfs_for_each_xattr+0x1a4/0xb40 fs/reiserfs/xattr.c:252
       reiserfs_delete_xattrs+0x1b/0x80 fs/reiserfs/xattr.c:364
       reiserfs_evict_inode+0x20c/0x460 fs/reiserfs/inode.c:53
       evict+0x2a4/0x620 fs/inode.c:587
       reiserfs_create+0x5a7/0x6e0 fs/reiserfs/namei.c:688
       lookup_open fs/namei.c:3392 [inline]
       open_last_lookups fs/namei.c:3462 [inline]
       path_openat+0x12f6/0x2f20 fs/namei.c:3669
       do_filp_open+0x21c/0x460 fs/namei.c:3699
       do_sys_openat2+0x13b/0x500 fs/open.c:1211
       do_sys_open fs/open.c:1227 [inline]
       __do_sys_open fs/open.c:1235 [inline]
       __se_sys_open fs/open.c:1231 [inline]
       __x64_sys_open+0x221/0x270 fs/open.c:1231
       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+0x61/0xcb

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->lock);
                               lock(&type->i_mutex_dir_key#8/3);
                               lock(&sbi->lock);
  lock(&type->i_mutex_dir_key#8/3);

 *** DEADLOCK ***

3 locks held by syz-executor.3/14767:
 #0: ffff88807d3c2460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff8880836c9020 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff8880836c9020 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: open_last_lookups fs/namei.c:3459 [inline]
 #1: ffff8880836c9020 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: path_openat+0x824/0x2f20 fs/namei.c:3669
 #2: ffff88807a90b090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x5b/0xd0 fs/reiserfs/lock.c:78

stack backtrace:
CPU: 0 PID: 14767 Comm: syz-executor.3 Not tainted 5.15.106-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
 down_write_nested+0xa0/0x180 kernel/locking/rwsem.c:1657
 inode_lock_nested include/linux/fs.h:822 [inline]
 open_xa_root fs/reiserfs/xattr.c:127 [inline]
 open_xa_dir+0x132/0x610 fs/reiserfs/xattr.c:152
 reiserfs_for_each_xattr+0x1a4/0xb40 fs/reiserfs/xattr.c:252
 reiserfs_delete_xattrs+0x1b/0x80 fs/reiserfs/xattr.c:364
 reiserfs_evict_inode+0x20c/0x460 fs/reiserfs/inode.c:53
 evict+0x2a4/0x620 fs/inode.c:587
 reiserfs_create+0x5a7/0x6e0 fs/reiserfs/namei.c:688
 lookup_open fs/namei.c:3392 [inline]
 open_last_lookups fs/namei.c:3462 [inline]
 path_openat+0x12f6/0x2f20 fs/namei.c:3669
 do_filp_open+0x21c/0x460 fs/namei.c:3699
 do_sys_openat2+0x13b/0x500 fs/open.c:1211
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_open fs/open.c:1235 [inline]
 __se_sys_open fs/open.c:1231 [inline]
 __x64_sys_open+0x221/0x270 fs/open.c:1231
 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+0x61/0xcb
RIP: 0033:0x7f8174607169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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:00007f816ab58168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f8174727050 RCX: 00007f8174607169
RDX: 0000000000000080 RSI: cbbba55452887f4a RDI: 0000000020000000
RBP: 00007f8174662ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe822b1eff R14: 00007f816ab58300 R15: 0000000000022000
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/11 04:34 linux-5.15.y d86dfc4d95cd 71147e29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in open_xa_dir
2023/04/25 19:04 linux-5.15.y 3299fb36854f 65320f8e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in open_xa_dir
2023/04/20 15:13 linux-5.15.y 3299fb36854f a219f34e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in open_xa_dir
2023/04/19 11:21 linux-5.15.y 4fdad925aa1a 94b4184e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in open_xa_dir
* Struck through repros no longer work on HEAD.