syzbot


possible deadlock in iterate_dir

Status: auto-obsoleted due to no activity on 2023/12/01 22:38
Subsystems: reiserfs
[Documentation on labels]
Reported-by: syzbot+435320768a3c52aa94b6@syzkaller.appspotmail.com
First crash: 454d, last: 208d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [reiserfs?] possible deadlock in iterate_dir 0 (1) 2022/12/24 12:14
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in iterate_dir 2 243d 248d 0/3 auto-obsoleted due to no activity on 2023/10/27 20:39
linux-4.14 possible deadlock in iterate_dir ubifs C 11375 377d 1372d 0/1 upstream: reported C repro on 2020/06/15 06:16
linux-5.15 possible deadlock in iterate_dir (2) 2 110d 203d 0/3 auto-obsoleted due to no activity on 2024/03/08 13:21
linux-4.19 possible deadlock in iterate_dir 1 1544d 1544d 0/1 auto-closed as invalid on 2020/04/24 15:06
linux-5.15 possible deadlock in iterate_dir 1 357d 357d 0/3 auto-obsoleted due to no activity on 2023/07/25 13:55

Sample crash report:
REISERFS (device loop5): using 3.5.x disk format
REISERFS warning (device loop5): vs-13060 reiserfs_update_sd_size: stat data of object [1 2 0x0 SD] (nlink == 1) not found (pos 2)
REISERFS (device loop5): Created .reiserfs_priv - reserved for xattr storage.
======================================================
WARNING: possible circular locking dependency detected
6.5.0-rc6-syzkaller-00038-g16931859a650 #0 Not tainted
------------------------------------------------------
syz-executor.5/16782 is trying to acquire lock:
ffff88802c481090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27

but task is already holding lock:
ffff888084d94410 (sb_writers#20){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2208 [inline]
ffff888084d94410 (sb_writers#20){.+.+}-{0:0}, at: iterate_dir+0x463/0x5f0 fs/readdir.c:109

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (sb_writers#20){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1494 [inline]
       sb_start_write include/linux/fs.h:1569 [inline]
       mnt_want_write_file+0x98/0x600 fs/namespace.c:447
       reiserfs_ioctl+0x19e/0x320 fs/reiserfs/ioctl.c:103
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl fs/ioctl.c:856 [inline]
       __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:856
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&sbi->lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3142 [inline]
       check_prevs_add kernel/locking/lockdep.c:3261 [inline]
       validate_chain kernel/locking/lockdep.c:3876 [inline]
       __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5144
       lock_acquire kernel/locking/lockdep.c:5761 [inline]
       lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747
       reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27
       reiserfs_dirty_inode+0xe6/0x270 fs/reiserfs/super.c:704
       __mark_inode_dirty+0x1e0/0xd50 fs/fs-writeback.c:2430
       generic_update_time fs/inode.c:1900 [inline]
       inode_update_time fs/inode.c:1913 [inline]
       touch_atime+0x70f/0x7e0 fs/inode.c:1985
       file_accessed include/linux/fs.h:2208 [inline]
       iterate_dir+0x463/0x5f0 fs/readdir.c:109
       __do_sys_getdents64 fs/readdir.c:405 [inline]
       __se_sys_getdents64 fs/readdir.c:390 [inline]
       __x64_sys_getdents64+0x14f/0x2e0 fs/readdir.c:390
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(sb_writers#20);
                               lock(&sbi->lock);
                               lock(sb_writers#20);
  lock(&sbi->lock);

 *** DEADLOCK ***

3 locks held by syz-executor.5/16782:
 #0: ffff88801f911d88 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe7/0x170 fs/file.c:1062
 #1: ffff88803f8bba00 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: iterate_dir+0xe4/0x5f0 fs/readdir.c:99
 #2: ffff888084d94410 (sb_writers#20){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2208 [inline]
 #2: ffff888084d94410 (sb_writers#20){.+.+}-{0:0}, at: iterate_dir+0x463/0x5f0 fs/readdir.c:109

stack backtrace:
CPU: 0 PID: 16782 Comm: syz-executor.5 Not tainted 6.5.0-rc6-syzkaller-00038-g16931859a650 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2195
 check_prev_add kernel/locking/lockdep.c:3142 [inline]
 check_prevs_add kernel/locking/lockdep.c:3261 [inline]
 validate_chain kernel/locking/lockdep.c:3876 [inline]
 __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5144
 lock_acquire kernel/locking/lockdep.c:5761 [inline]
 lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747
 reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27
 reiserfs_dirty_inode+0xe6/0x270 fs/reiserfs/super.c:704
 __mark_inode_dirty+0x1e0/0xd50 fs/fs-writeback.c:2430
 generic_update_time fs/inode.c:1900 [inline]
 inode_update_time fs/inode.c:1913 [inline]
 touch_atime+0x70f/0x7e0 fs/inode.c:1985
 file_accessed include/linux/fs.h:2208 [inline]
 iterate_dir+0x463/0x5f0 fs/readdir.c:109
 __do_sys_getdents64 fs/readdir.c:405 [inline]
 __se_sys_getdents64 fs/readdir.c:390 [inline]
 __x64_sys_getdents64+0x14f/0x2e0 fs/readdir.c:390
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5f77a7cae9
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:00007f5f788bd0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f5f77b9bf80 RCX: 00007f5f77a7cae9
RDX: 00000000000000fc RSI: 0000000020000a00 RDI: 0000000000000004
RBP: 00007f5f77ac847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f5f77b9bf80 R15: 00007fff1bbfd018
 </TASK>
REISERFS warning (device loop5): vs-13060 reiserfs_update_sd_size: stat data of object [1 2 0x0 SD] (nlink == 1) not found (pos 2)

Crashes (23):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/17 22:41 upstream 16931859a650 74b106b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root possible deadlock in iterate_dir
2023/06/23 02:20 upstream 8a28a0b6f1a1 79782afc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/20 07:53 upstream 789b4a41c247 a219f34e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/07 22:47 upstream aa318c48808c 71147e29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/07 06:14 upstream f2afccfefe7b 00ce4c67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/07 01:15 upstream f2afccfefe7b 00ce4c67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/06 21:10 upstream f2afccfefe7b 00ce4c67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/06 20:38 upstream f2afccfefe7b 08707520 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/04/06 09:43 upstream 99ddf2254feb 08707520 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/03/28 17:35 upstream 3a93e40326c8 fc067f05 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/03/28 15:13 upstream 3a93e40326c8 47f3aaf1 .config console log report info ci2-upstream-fs possible deadlock in iterate_dir
2023/03/28 00:39 upstream 3a93e40326c8 47f3aaf1 .config console log report info ci2-upstream-fs possible deadlock in iterate_dir
2023/03/23 18:13 upstream fff5a5e7f528 f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/03/16 20:23 upstream 0ddc84d2dd43 18b58603 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/03/16 20:07 upstream 0ddc84d2dd43 18b58603 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/03/15 23:16 upstream 9c1bec9c0b08 18b58603 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/03/02 20:19 upstream 04a357b1f6f0 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/02/21 21:05 upstream 9e58df973d22 42a4d508 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/02/20 22:15 upstream 91bc559d8d3a 2414209c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2023/02/17 16:49 upstream ec35307e18ba cf8c2d39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in iterate_dir
2022/12/20 12:08 upstream 6feb57c2fd7c d3e76707 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in iterate_dir
2023/08/23 22:37 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 35e2132122ba 4d7ae7ab .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in iterate_dir
2023/03/23 20:36 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in iterate_dir
* Struck through repros no longer work on HEAD.