syzbot


possible deadlock in diFree

Status: upstream: reported on 2025/03/25 19:22
Reported-by: syzbot+f686d12bdef997d7bc5a@syzkaller.appspotmail.com
First crash: 31d, last: 31d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in diFree (2) jfs C 40 30d 155d 25/28 upstream: reported C repro on 2024/11/21 12:18
upstream possible deadlock in diFree jfs 91 262d 368d 0/28 auto-obsoleted due to no activity on 2024/10/15 15:16

Sample crash report:
ERROR: (device loop8): xtSearch: XT_GETPAGE: xtree page corrupt
ERROR: (device loop8): remounting filesystem as read-only
ERROR: (device loop8): duplicateIXtree: 
============================================
WARNING: possible recursive locking detected
6.1.131-syzkaller #0 Not tainted
--------------------------------------------
syz.8.1670/11821 is trying to acquire lock:
ffff888058570920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diFree+0x378/0x2fb0 fs/jfs/jfs_imap.c:889

but task is already holding lock:
ffff888058570920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diAlloc+0x1b2/0x1630

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(imap->im_aglock[index]));
  lock(&(imap->im_aglock[index]));

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz.8.1670/11821:
 #0: ffff888056fae460 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff88804cca33c0 (&type->i_mutex_dir_key#11/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88804cca33c0 (&type->i_mutex_dir_key#11/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876
 #2: ffff888058570920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diAlloc+0x1b2/0x1630
 #3: ffff888058570890 (&imap->im_freelock){+.+.}-{3:3}, at: diNewIAG fs/jfs/jfs_imap.c:2460 [inline]
 #3: ffff888058570890 (&imap->im_freelock){+.+.}-{3:3}, at: diAllocExt fs/jfs/jfs_imap.c:1905 [inline]
 #3: ffff888058570890 (&imap->im_freelock){+.+.}-{3:3}, at: diAllocAG+0x4af/0x1e50 fs/jfs/jfs_imap.c:1669
 #4: ffff88804cca2638 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diNewIAG fs/jfs/jfs_imap.c:2477 [inline]
 #4: ffff88804cca2638 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diAllocExt fs/jfs/jfs_imap.c:1905 [inline]
 #4: ffff88804cca2638 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diAllocAG+0x861/0x1e50 fs/jfs/jfs_imap.c:1669

stack backtrace:
CPU: 0 PID: 11821 Comm: syz.8.1670 Not tainted 6.1.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2983 [inline]
 check_deadlock kernel/locking/lockdep.c:3026 [inline]
 validate_chain+0x4711/0x5950 kernel/locking/lockdep.c:3812
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
 diFree+0x378/0x2fb0 fs/jfs/jfs_imap.c:889
 jfs_evict_inode+0x329/0x440 fs/jfs/inode.c:156
 evict+0x529/0x930 fs/inode.c:705
 diFreeSpecial fs/jfs/jfs_imap.c:552 [inline]
 duplicateIXtree+0x3c2/0x540 fs/jfs/jfs_imap.c:3022
 diNewIAG fs/jfs/jfs_imap.c:2597 [inline]
 diAllocExt fs/jfs/jfs_imap.c:1905 [inline]
 diAllocAG+0x17d4/0x1e50 fs/jfs/jfs_imap.c:1669
 diAlloc+0x1ce/0x1630 fs/jfs/jfs_imap.c:1590
 ialloc+0x8a/0x980 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x1c1/0xbb0 fs/jfs/namei.c:225
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4106
 do_mkdirat+0x225/0x360 fs/namei.c:4131
 __do_sys_mkdirat fs/namei.c:4146 [inline]
 __se_sys_mkdirat fs/namei.c:4144 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4144
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0a6bb8d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0a6c9bf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f0a6bda6080 RCX: 00007f0a6bb8d169
RDX: 0000000000000000 RSI: 00002000000005c0 RDI: ffffffffffffff9c
RBP: 00007f0a6bc0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0a6bda6080 R15: 00007ffdb63430e8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/25 19:21 linux-6.1.y 344a09659766 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in diFree
* Struck through repros no longer work on HEAD.