syzbot


possible deadlock in jfs_create

Status: upstream: reported on 2024/06/25 02:53
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+bdacb5fa2bf85deafea9@syzkaller.appspotmail.com
First crash: 28d, last: 28d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [jfs?] possible deadlock in jfs_create 0 (1) 2024/06/25 02:53

Sample crash report:
loop2: detected capacity change from 0 to 32768
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0 Not tainted
------------------------------------------------------
syz-executor.2/9183 is trying to acquire lock:
ffff88804c874288 (&jfs_ip->commit_mutex/1){+.+.}-{3:3}, at: jfs_create+0x2c3/0xb40 fs/jfs/namei.c:101

but task is already holding lock:
ffff88804c873948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_create+0x2a7/0xb40 fs/jfs/namei.c:100

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&jfs_ip->commit_mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       diNewIAG fs/jfs/jfs_imap.c:2519 [inline]
       diAllocExt fs/jfs/jfs_imap.c:1902 [inline]
       diAllocAG+0xc59/0x2300 fs/jfs/jfs_imap.c:1666
       diAlloc+0x8f7/0x1a70 fs/jfs/jfs_imap.c:1587
       ialloc+0x84/0x9e0 fs/jfs/jfs_inode.c:56
       jfs_mkdir+0x244/0xb30 fs/jfs/namei.c:225
       vfs_mkdir+0x57d/0x860 fs/namei.c:4131
       do_mkdirat+0x301/0x3a0 fs/namei.c:4154
       __do_sys_mkdir fs/namei.c:4174 [inline]
       __se_sys_mkdir fs/namei.c:4172 [inline]
       __ia32_sys_mkdir+0xf0/0x140 fs/namei.c:4172
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
       entry_SYSENTER_compat_after_hwframe+0x84/0x8e

-> #4 (&jfs_ip->rdwrlock/1){++++}-{3:3}:
       __lock_release kernel/locking/lockdep.c:5468 [inline]
       lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
       __mutex_unlock_slowpath+0xa3/0x650 kernel/locking/mutex.c:912
       diNewIAG fs/jfs/jfs_imap.c:2634 [inline]
       diAllocExt fs/jfs/jfs_imap.c:1902 [inline]
       diAllocAG+0x912/0x2300 fs/jfs/jfs_imap.c:1666
       diAlloc+0x8f7/0x1a70 fs/jfs/jfs_imap.c:1587
       ialloc+0x84/0x9e0 fs/jfs/jfs_inode.c:56
       jfs_mkdir+0x244/0xb30 fs/jfs/namei.c:225
       vfs_mkdir+0x57d/0x860 fs/namei.c:4131
       do_mkdirat+0x301/0x3a0 fs/namei.c:4154
       __do_sys_mkdir fs/namei.c:4174 [inline]
       __se_sys_mkdir fs/namei.c:4172 [inline]
       __ia32_sys_mkdir+0xf0/0x140 fs/namei.c:4172
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
       entry_SYSENTER_compat_after_hwframe+0x84/0x8e

-> #3 (&(imap->im_aglock[index])){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       diFree+0x2ff/0x2770 fs/jfs/jfs_imap.c:886
       jfs_evict_inode+0x3d4/0x4b0 fs/jfs/inode.c:156
       evict+0x2ed/0x6c0 fs/inode.c:667
       iput_final fs/inode.c:1741 [inline]
       iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
       iput+0x5c/0x80 fs/inode.c:1757
       dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
       __dentry_kill+0x1d0/0x600 fs/dcache.c:603
       shrink_kill fs/dcache.c:1048 [inline]
       shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075
       prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156
       super_cache_scan+0x32a/0x550 fs/super.c:221
       do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
       shrink_slab_memcg mm/shrinker.c:548 [inline]
       shrink_slab+0xa87/0x1310 mm/shrinker.c:626
       shrink_one+0x493/0x7c0 mm/vmscan.c:4790
       shrink_many mm/vmscan.c:4851 [inline]
       lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
       shrink_node mm/vmscan.c:5910 [inline]
       kswapd_shrink_node mm/vmscan.c:6720 [inline]
       balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
       kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
       kthread+0x2c1/0x3a0 kernel/kthread.c:389
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #2 (fs_reclaim){+.+.}-{0:0}:
       __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
       fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
       might_alloc include/linux/sched/mm.h:334 [inline]
       slab_pre_alloc_hook mm/slub.c:3891 [inline]
       slab_alloc_node mm/slub.c:3981 [inline]
       __do_kmalloc_node mm/slub.c:4121 [inline]
       __kmalloc_noprof+0xb5/0x420 mm/slub.c:4135
       kmalloc_noprof include/linux/slab.h:664 [inline]
       ea_get+0x21f/0x12c0 fs/jfs/xattr.c:487
       __jfs_setxattr+0x1ed/0xfb0 fs/jfs/xattr.c:720
       __jfs_xattr_set+0xc6/0x150 fs/jfs/xattr.c:919
       __vfs_setxattr+0x173/0x1e0 fs/xattr.c:200
       __vfs_setxattr_noperm+0x127/0x660 fs/xattr.c:234
       __vfs_setxattr_locked+0x182/0x260 fs/xattr.c:295
       vfs_setxattr+0x146/0x350 fs/xattr.c:321
       do_setxattr+0x146/0x170 fs/xattr.c:629
       setxattr+0x15d/0x180 fs/xattr.c:652
       path_setxattr+0x179/0x1e0 fs/xattr.c:671
       __do_sys_lsetxattr fs/xattr.c:694 [inline]
       __se_sys_lsetxattr fs/xattr.c:690 [inline]
       __ia32_sys_lsetxattr+0xbd/0x160 fs/xattr.c:690
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
       entry_SYSENTER_compat_after_hwframe+0x84/0x8e

-> #1 (&jfs_ip->xattr_sem){++++}-{3:3}:
       down_read+0x9a/0x330 kernel/locking/rwsem.c:1526
       __jfs_getxattr+0xee/0x360 fs/jfs/xattr.c:807
       jfs_get_acl+0x7c/0x170 fs/jfs/acl.c:38
       __get_acl+0x378/0x4e0 fs/posix_acl.c:159
       get_inode_acl fs/posix_acl.c:184 [inline]
       posix_acl_create+0x14c/0x5f0 fs/posix_acl.c:647
       jfs_init_acl+0x9a/0x3a0 fs/jfs/acl.c:135
       jfs_mkdir+0x2df/0xb30 fs/jfs/namei.c:236
       vfs_mkdir+0x57d/0x860 fs/namei.c:4131
       do_mkdirat+0x301/0x3a0 fs/namei.c:4154
       __do_sys_mkdir fs/namei.c:4174 [inline]
       __se_sys_mkdir fs/namei.c:4172 [inline]
       __ia32_sys_mkdir+0xf0/0x140 fs/namei.c:4172
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
       entry_SYSENTER_compat_after_hwframe+0x84/0x8e

-> #0 (&jfs_ip->commit_mutex/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
       lock_acquire kernel/locking/lockdep.c:5754 [inline]
       lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       jfs_create+0x2c3/0xb40 fs/jfs/namei.c:101
       lookup_open.isra.0+0x10a1/0x13c0 fs/namei.c:3505
       open_last_lookups fs/namei.c:3574 [inline]
       path_openat+0x92f/0x29f0 fs/namei.c:3804
       do_filp_open+0x1dc/0x430 fs/namei.c:3834
       do_sys_openat2+0x17a/0x1e0 fs/open.c:1405
       do_sys_open fs/open.c:1420 [inline]
       __do_compat_sys_openat fs/open.c:1480 [inline]
       __se_compat_sys_openat fs/open.c:1478 [inline]
       __ia32_compat_sys_openat+0x16e/0x210 fs/open.c:1478
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
       entry_SYSENTER_compat_after_hwframe+0x84/0x8e

other info that might help us debug this:

Chain exists of:
  &jfs_ip->commit_mutex/1 --> &jfs_ip->rdwrlock/1 --> &jfs_ip->commit_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&jfs_ip->commit_mutex);
                               lock(&jfs_ip->rdwrlock/1);
                               lock(&jfs_ip->commit_mutex);
  lock(&jfs_ip->commit_mutex/1);

 *** DEADLOCK ***

3 locks held by syz-executor.2/9183:
 #0: ffff888057d1c420 (sb_writers#29){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:3563 [inline]
 #0: ffff888057d1c420 (sb_writers#29){.+.+}-{0:0}, at: path_openat+0x19e6/0x29f0 fs/namei.c:3804
 #1: ffff88804c873d00 (&type->i_mutex_dir_key#13){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
 #1: ffff88804c873d00 (&type->i_mutex_dir_key#13){++++}-{3:3}, at: open_last_lookups fs/namei.c:3571 [inline]
 #1: ffff88804c873d00 (&type->i_mutex_dir_key#13){++++}-{3:3}, at: path_openat+0x8c7/0x29f0 fs/namei.c:3804
 #2: ffff88804c873948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_create+0x2a7/0xb40 fs/jfs/namei.c:100

stack backtrace:
CPU: 3 PID: 9183 Comm: syz-executor.2 Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
 jfs_create+0x2c3/0xb40 fs/jfs/namei.c:101
 lookup_open.isra.0+0x10a1/0x13c0 fs/namei.c:3505
 open_last_lookups fs/namei.c:3574 [inline]
 path_openat+0x92f/0x29f0 fs/namei.c:3804
 do_filp_open+0x1dc/0x430 fs/namei.c:3834
 do_sys_openat2+0x17a/0x1e0 fs/open.c:1405
 do_sys_open fs/open.c:1420 [inline]
 __do_compat_sys_openat fs/open.c:1480 [inline]
 __se_compat_sys_openat fs/open.c:1478 [inline]
 __ia32_compat_sys_openat+0x16e/0x210 fs/open.c:1478
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf72ca579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f5ebc5ac EFLAGS: 00000292 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000020000040
RDX: 000000000000275a RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/21 02:47 upstream 50736169ecc8 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 possible deadlock in jfs_create
* Struck through repros no longer work on HEAD.