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possible deadlock in delete_one_xattr

Status: upstream: reported C repro on 2024/04/30 00:40
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+bd323360d0326f7b2b54@syzkaller.appspotmail.com
First crash: 207d, last: 27d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/05/01 upstream (ToT) 18daea77cca6 C [report] possible deadlock in delete_one_xattr
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 possible deadlock in delete_one_xattr reiserfs 2 653d 714d 0/1 upstream: reported on 2022/12/10 02:38
upstream possible deadlock in delete_one_xattr (2) reiserfs C done error 4 352d 631d 0/28 auto-obsoleted due to no activity on 2024/03/16 04:41
linux-6.1 possible deadlock in delete_one_xattr 15 64d 100d 0/3 upstream: reported on 2024/08/14 16:50
upstream possible deadlock in delete_one_xattr reiserfs C error 4 653d 654d 0/28 closed as invalid on 2023/02/08 16:28
linux-4.14 possible deadlock in delete_one_xattr reiserfs 1 653d 653d 0/1 upstream: reported on 2023/02/08 17:45
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/10/07 06:44 15m retest repro linux-5.15.y report log

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.15.157-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor214/4052 is trying to acquire lock:
ffff0000df2b4bc0 (&type->i_mutex_dir_key#6/2){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
ffff0000df2b4bc0 (&type->i_mutex_dir_key#6/2){+.+.}-{3:3}, at: xattr_rmdir fs/reiserfs/xattr.c:106 [inline]
ffff0000df2b4bc0 (&type->i_mutex_dir_key#6/2){+.+.}-{3:3}, at: delete_one_xattr+0xe8/0x2c8 fs/reiserfs/xattr.c:338

but task is already holding lock:
ffff0000df2b37e0 (&type->i_mutex_dir_key#6/3){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
ffff0000df2b37e0 (&type->i_mutex_dir_key#6/3){+.+.}-{3:3}, at: reiserfs_for_each_xattr+0x788/0x8d8 fs/reiserfs/xattr.c:309

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&type->i_mutex_dir_key#6/3){+.+.}-{3:3}:
       down_write_nested+0xc0/0x130 kernel/locking/rwsem.c:1667
       inode_lock_nested include/linux/fs.h:824 [inline]
       open_xa_root fs/reiserfs/xattr.c:127 [inline]
       open_xa_dir+0x11c/0x578 fs/reiserfs/xattr.c:152
       xattr_lookup+0x3c/0x268 fs/reiserfs/xattr.c:395
       reiserfs_xattr_set_handle+0xe4/0xc10 fs/reiserfs/xattr.c:540
       reiserfs_xattr_set+0x398/0x4b0 fs/reiserfs/xattr.c:640
       trusted_set+0x98/0xec fs/reiserfs/xattr_trusted.c:31
       __vfs_setxattr+0x388/0x3a4 fs/xattr.c:182
       __vfs_setxattr_noperm+0x110/0x528 fs/xattr.c:216
       __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:277
       vfs_setxattr+0x1a8/0x344 fs/xattr.c:303
       do_setxattr fs/xattr.c:588 [inline]
       setxattr+0x250/0x2b4 fs/xattr.c:611
       path_setxattr+0x17c/0x258 fs/xattr.c:630
       __do_sys_lsetxattr fs/xattr.c:653 [inline]
       __se_sys_lsetxattr fs/xattr.c:649 [inline]
       __arm64_sys_lsetxattr+0xbc/0xd8 fs/xattr.c:649
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #1 (&type->i_mutex_dir_key#6){+.+.}-{3:3}:
       down_write+0xbc/0x12c kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:789 [inline]
       vfs_rename+0x68c/0xe04 fs/namei.c:4797
       do_renameat2+0xa00/0x10c0 fs/namei.c:4985
       __do_sys_renameat2 fs/namei.c:5018 [inline]
       __se_sys_renameat2 fs/namei.c:5015 [inline]
       __arm64_sys_renameat2+0xe0/0xfc fs/namei.c:5015
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #0 (&type->i_mutex_dir_key#6/2){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
       lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
       down_write_nested+0xc0/0x130 kernel/locking/rwsem.c:1667
       inode_lock_nested include/linux/fs.h:824 [inline]
       xattr_rmdir fs/reiserfs/xattr.c:106 [inline]
       delete_one_xattr+0xe8/0x2c8 fs/reiserfs/xattr.c:338
       reiserfs_for_each_xattr+0x794/0x8d8 fs/reiserfs/xattr.c:311
       reiserfs_delete_xattrs+0x2c/0xa4 fs/reiserfs/xattr.c:364
       reiserfs_evict_inode+0x1dc/0x3f0 fs/reiserfs/inode.c:53
       evict+0x260/0x68c fs/inode.c:587
       iput_final fs/inode.c:1705 [inline]
       iput+0x744/0x824 fs/inode.c:1731
       d_delete_notify include/linux/fsnotify.h:261 [inline]
       vfs_rmdir+0x2f8/0x3f0 fs/namei.c:4162
       do_rmdir+0x2e8/0x84c fs/namei.c:4210
       __do_sys_unlinkat fs/namei.c:4390 [inline]
       __se_sys_unlinkat fs/namei.c:4384 [inline]
       __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4384
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

other info that might help us debug this:

Chain exists of:
  &type->i_mutex_dir_key#6/2 --> &type->i_mutex_dir_key#6 --> &type->i_mutex_dir_key#6/3

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&type->i_mutex_dir_key#6/3);
                               lock(&type->i_mutex_dir_key#6);
                               lock(&type->i_mutex_dir_key#6/3);
  lock(&type->i_mutex_dir_key#6/2);

 *** DEADLOCK ***

3 locks held by syz-executor214/4052:
 #0: ffff0000c8196460 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:377
 #1: ffff0000df301020 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
 #1: ffff0000df301020 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_rmdir+0x1e0/0x84c fs/namei.c:4197
 #2: ffff0000df2b37e0 (&type->i_mutex_dir_key#6/3){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
 #2: ffff0000df2b37e0 (&type->i_mutex_dir_key#6/3){+.+.}-{3:3}, at: reiserfs_for_each_xattr+0x788/0x8d8 fs/reiserfs/xattr.c:309

stack backtrace:
CPU: 1 PID: 4052 Comm: syz-executor214 Not tainted 5.15.157-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
 check_noncircular+0x2cc/0x378 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 kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
 down_write_nested+0xc0/0x130 kernel/locking/rwsem.c:1667
 inode_lock_nested include/linux/fs.h:824 [inline]
 xattr_rmdir fs/reiserfs/xattr.c:106 [inline]
 delete_one_xattr+0xe8/0x2c8 fs/reiserfs/xattr.c:338
 reiserfs_for_each_xattr+0x794/0x8d8 fs/reiserfs/xattr.c:311
 reiserfs_delete_xattrs+0x2c/0xa4 fs/reiserfs/xattr.c:364
 reiserfs_evict_inode+0x1dc/0x3f0 fs/reiserfs/inode.c:53
 evict+0x260/0x68c fs/inode.c:587
 iput_final fs/inode.c:1705 [inline]
 iput+0x744/0x824 fs/inode.c:1731
 d_delete_notify include/linux/fsnotify.h:261 [inline]
 vfs_rmdir+0x2f8/0x3f0 fs/namei.c:4162
 do_rmdir+0x2e8/0x84c fs/namei.c:4210
 __do_sys_unlinkat fs/namei.c:4390 [inline]
 __se_sys_unlinkat fs/namei.c:4384 [inline]
 __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4384
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/30 04:22 linux-5.15.y b925f60c6ee7 f10afd69 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan-arm64 possible deadlock in delete_one_xattr
2024/08/12 15:23 linux-5.15.y 7e89efd3ae1c 842184b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in delete_one_xattr
2024/08/12 15:23 linux-5.15.y 7e89efd3ae1c 842184b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in delete_one_xattr
2024/08/12 15:23 linux-5.15.y 7e89efd3ae1c 842184b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in delete_one_xattr
2024/07/14 17:18 linux-5.15.y f45bea23c39c eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in delete_one_xattr
2024/07/14 17:05 linux-5.15.y f45bea23c39c eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in delete_one_xattr
2024/07/14 16:38 linux-5.15.y f45bea23c39c eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in delete_one_xattr
2024/10/26 05:46 linux-5.15.y 74cdd62cb470 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in delete_one_xattr
2024/04/30 00:39 linux-5.15.y b925f60c6ee7 f10afd69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in delete_one_xattr
* Struck through repros no longer work on HEAD.