[syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    1fb918967b56 Merge tag 'for-6.11-rc3-tag' of git://git.ker..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14b8bbd9980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7229118d88b4a71b
dashboard link: https://syzkaller.appspot.com/bug?extid=1fed2de07d8e11a3ec1b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1142e5ed980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14aa396b980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-1fb91896.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cd6e8883313a/vmlinux-1fb91896.xz
kernel image: https://storage.googleapis.com/syzbot-assets/87b718d2d1df/bzImage-1fb91896.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6b8f724adfab/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1fed2de07d8e11a3ec1b@syzkaller.appspotmail.com

Code: c4 28 c3 e8 01 1a 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 83 c8 ff c3 66 2e 0f 1f
======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc3-syzkaller-00066-g1fb918967b56 #0 Not tainted
------------------------------------------------------
syz-executor622/5097 is trying to acquire lock:
ffff88803ec0bf60 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_try_remove_refcount_tree+0xb6/0x330 fs/ocfs2/refcounttree.c:931

but task is already holding lock:
ffff88803ec0bff8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_try_remove_refcount_tree+0xa5/0x330 fs/ocfs2/refcounttree.c:930

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&oi->ip_xattr_sem){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526
       ocfs2_init_acl+0x397/0x930 fs/ocfs2/acl.c:366
       ocfs2_mknod+0x1c05/0x2b40 fs/ocfs2/namei.c:408
       ocfs2_create+0x1ab/0x480 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       file_open_name fs/open.c:1361 [inline]
       filp_open+0x261/0x2d0 fs/open.c:1381
       do_coredump+0x2259/0x2a30 fs/coredump.c:708
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #3 (jbd2_handle){.+.+}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       start_this_handle+0x1eb4/0x2110 fs/jbd2/transaction.c:448
       jbd2__journal_start+0x2da/0x5d0 fs/jbd2/transaction.c:505
       jbd2_journal_start+0x29/0x40 fs/jbd2/transaction.c:544
       ocfs2_start_trans+0x3c9/0x700 fs/ocfs2/journal.c:352
       ocfs2_mknod+0x150c/0x2b40 fs/ocfs2/namei.c:359
       ocfs2_create+0x1ab/0x480 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       file_open_name fs/open.c:1361 [inline]
       filp_open+0x261/0x2d0 fs/open.c:1381
       do_coredump+0x2259/0x2a30 fs/coredump.c:708
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #2 (&journal->j_trans_barrier){.+.+}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526
       ocfs2_start_trans+0x3be/0x700 fs/ocfs2/journal.c:350
       ocfs2_mknod+0x150c/0x2b40 fs/ocfs2/namei.c:359
       ocfs2_create+0x1ab/0x480 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       file_open_name fs/open.c:1361 [inline]
       filp_open+0x261/0x2d0 fs/open.c:1381
       do_coredump+0x2259/0x2a30 fs/coredump.c:708
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #1 (sb_internal#2){.+.+}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1675 [inline]
       sb_start_intwrite include/linux/fs.h:1858 [inline]
       ocfs2_start_trans+0x2b9/0x700 fs/ocfs2/journal.c:348
       ocfs2_orphan_for_truncate fs/ocfs2/file.c:396 [inline]
       ocfs2_truncate_file+0x68c/0x1560 fs/ocfs2/file.c:500
       ocfs2_setattr+0x1217/0x1f50 fs/ocfs2/file.c:1208
       notify_change+0xb9d/0xe70 fs/attr.c:495
       do_truncate+0x220/0x310 fs/open.c:65
       do_coredump+0x2702/0x2a30 fs/coredump.c:744
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #0 (&oi->ip_alloc_sem){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
       __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_write+0x99/0x220 kernel/locking/rwsem.c:1579
       ocfs2_try_remove_refcount_tree+0xb6/0x330 fs/ocfs2/refcounttree.c:931
       ocfs2_truncate_file+0xe08/0x1560 fs/ocfs2/file.c:521
       ocfs2_setattr+0x1217/0x1f50 fs/ocfs2/file.c:1208
       notify_change+0xb9d/0xe70 fs/attr.c:495
       do_truncate+0x220/0x310 fs/open.c:65
       do_coredump+0x2702/0x2a30 fs/coredump.c:744
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

other info that might help us debug this:

Chain exists of:
  &oi->ip_alloc_sem --> jbd2_handle --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(jbd2_handle);
                               lock(&oi->ip_xattr_sem);
  lock(&oi->ip_alloc_sem);

 *** DEADLOCK ***

2 locks held by syz-executor622/5097:
 #0: ffff88803ec0c2c0 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #0: ffff88803ec0c2c0 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:63
 #1: ffff88803ec0bff8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_try_remove_refcount_tree+0xa5/0x330 fs/ocfs2/refcounttree.c:930

stack backtrace:
CPU: 0 UID: 0 PID: 5097 Comm: syz-executor622 Not tainted 6.11.0-rc3-syzkaller-00066-g1fb918967b56 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 down_write+0x99/0x220 kernel/locking/rwsem.c:1579
 ocfs2_try_remove_refcount_tree+0xb6/0x330 fs/ocfs2/refcounttree.c:931
 ocfs2_truncate_file+0xe08/0x1560 fs/ocfs2/file.c:521
 ocfs2_setattr+0x1217/0x1f50 fs/ocfs2/file.c:1208
 notify_change+0xb9d/0xe70 fs/attr.c:495
 do_truncate+0x220/0x310 fs/open.c:65
 do_coredump+0x2702/0x2a30 fs/coredump.c:744
 get_signal+0x13fa/0x1740 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f27cd76b711
Code: c4 28 c3 e8 01 1a 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:ffffffffffffffe0 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f27cd76b709
RDX: 0000000000000000 RSI: ffffffffffffffe0 RDI: 0000000004008011
RBP: 65756e69746e6f63 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 633d73726f727265
R13: 00007ffd27cfc3fc R14: 00007ffd27cfc440 R15: 00007ffd27cfc430
 </TASK>
OCFS2: ERROR (device loop0): int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *, handle_t *, u32, u32, struct ocfs2_suballoc_result *): Chain allocator dinode 23 has 4294967295 used bits but only 16777215 total
On-disk corruption discovered. Please run fsck.ocfs2 once the filesystem is unmounted.
OCFS2: Returning error to the calling process.
(syz-executor622,5097,0):ocfs2_claim_suballoc_bits:2038 ERROR: status = -5
(syz-executor622,5097,0):__ocfs2_claim_clusters:2412 ERROR: status = -5
(syz-executor622,5097,0):__ocfs2_claim_clusters:2420 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_local_alloc_new_window:1197 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_local_alloc_new_window:1222 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_local_alloc_slide_window:1296 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_local_alloc_slide_window:1315 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_reserve_local_alloc_bits:672 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_reserve_local_alloc_bits:710 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_reserve_clusters_with_limit:1170 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_reserve_clusters_with_limit:1219 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_convert_inline_data_to_extents:7080 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_try_to_write_inline_data:1564 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_write_begin_nolock:1676 ERROR: status = -5
(syz-executor622,5097,0):ocfs2_write_begin:1906 ERROR: status = -5
syz-executor622 (5097) used greatest stack depth: 17712 bytes left
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	28 c3                	sub    %al,%bl
   2:	e8 01 1a 00 00       	call   0x1a08
   7:	90                   	nop
   8:	48 89 f8             	mov    %rdi,%rax
   b:	48 89 f7             	mov    %rsi,%rdi
   e:	48 89 d6             	mov    %rdx,%rsi
  11:	48 89 ca             	mov    %rcx,%rdx
  14:	4d 89 c2             	mov    %r8,%r10
  17:	4d 89 c8             	mov    %r9,%r8
  1a:	4c 8b 4c 24 08       	mov    0x8(%rsp),%r9
  1f:	0f 05                	syscall
  21:	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax
  27:	73 01                	jae    0x2a
* 29:	c3                   	ret <-- trapping instruction
  2a:	48 c7 c1 b8 ff ff ff 	mov    $0xffffffffffffffb8,%rcx
  31:	f7 d8                	neg    %eax
  33:	64 89 01             	mov    %eax,%fs:(%rcx)
  36:	48 83 c8 ff          	or     $0xffffffffffffffff,%rax
  3a:	c3                   	ret
  3b:	66                   	data16
  3c:	2e                   	cs
  3d:	0f                   	.byte 0xf
  3e:	1f                   	(bad)


---
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Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[Edward Adam Davis]

use trylock to replace

#syz test: upstream 1fb918967b56

diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
index 62464d194da3..f60e3178fe74 100644
--- a/fs/ocfs2/acl.c
+++ b/fs/ocfs2/acl.c
@@ -363,7 +363,8 @@ int ocfs2_init_acl(handle_t *handle,
 
 	if (!S_ISLNK(inode->i_mode)) {
 		if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) {
-			down_read(&OCFS2_I(dir)->ip_xattr_sem);
+			if (!down_read_trylock(&OCFS2_I(dir)->ip_xattr_sem))
+				return -EBUSY;
 			acl = ocfs2_get_acl_nolock(dir, ACL_TYPE_DEFAULT,
 						   dir_bh);
 			up_read(&OCFS2_I(dir)->ip_xattr_sem);

Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in ocfs2_get_system_file_inode

======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc3-syzkaller-00066-g1fb918967b56-dirty #0 Not tainted
------------------------------------------------------
syz.0.18/5710 is trying to acquire lock:
ffff88804e4b95a8 (&osb->system_file_mutex){+.+.}-{3:3}, at: ocfs2_get_system_file_inode+0x18f/0x7b0 fs/ocfs2/sysfile.c:101

but task is already holding lock:
ffff888011b74da0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_write_begin+0x1d1/0x3a0 fs/ocfs2/aops.c:1901

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526
       ocfs2_read_virt_blocks+0x2ca/0xa50 fs/ocfs2/extent_map.c:976
       ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
       ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
       ocfs2_find_entry+0x43b/0x2780 fs/ocfs2/dir.c:1080
       ocfs2_find_files_on_disk+0xff/0x360 fs/ocfs2/dir.c:1980
       ocfs2_lookup_ino_from_name+0xb1/0x1e0 fs/ocfs2/dir.c:2002
       _ocfs2_get_system_file_inode fs/ocfs2/sysfile.c:136 [inline]
       ocfs2_get_system_file_inode+0x305/0x7b0 fs/ocfs2/sysfile.c:112
       ocfs2_init_global_system_inodes+0x32c/0x730 fs/ocfs2/super.c:457
       ocfs2_initialize_super fs/ocfs2/super.c:2250 [inline]
       ocfs2_fill_super+0x3068/0x5880 fs/ocfs2/super.c:994
       mount_bdev+0x20a/0x2d0 fs/super.c:1679
       legacy_get_tree+0xee/0x190 fs/fs_context.c:662
       vfs_get_tree+0x90/0x2a0 fs/super.c:1800
       do_new_mount+0x2be/0xb40 fs/namespace.c:3472
       do_mount fs/namespace.c:3812 [inline]
       __do_sys_mount fs/namespace.c:4020 [inline]
       __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&osb->system_file_mutex){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
       __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       ocfs2_get_system_file_inode+0x18f/0x7b0 fs/ocfs2/sysfile.c:101
       ocfs2_reserve_local_alloc_bits+0x107/0x2870 fs/ocfs2/localalloc.c:627
       ocfs2_reserve_clusters_with_limit+0x1b8/0xb60 fs/ocfs2/suballoc.c:1166
       ocfs2_convert_inline_data_to_extents+0x29d/0x17f0 fs/ocfs2/alloc.c:7078
       ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1562 [inline]
       ocfs2_write_begin_nolock+0x1c79/0x4d30 fs/ocfs2/aops.c:1669
       ocfs2_write_begin+0x205/0x3a0 fs/ocfs2/aops.c:1903
       generic_perform_write+0x399/0x840 mm/filemap.c:4019
       ocfs2_file_write_iter+0x17b4/0x1f60 fs/ocfs2/file.c:2455
       __kernel_write_iter+0x40d/0x900 fs/read_write.c:523
       __kernel_write+0x120/0x180 fs/read_write.c:543
       __dump_emit+0x237/0x360 fs/coredump.c:816
       elf_core_dump+0x35e0/0x4720 fs/binfmt_elf.c:2095
       do_coredump+0x1b04/0x2a30 fs/coredump.c:767
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_file_ip_alloc_sem_key);
                               lock(&osb->system_file_mutex);
                               lock(&ocfs2_file_ip_alloc_sem_key);
  lock(&osb->system_file_mutex);

 *** DEADLOCK ***

3 locks held by syz.0.18/5710:
 #0: ffff88804e4fc420 (sb_writers#12){.+.+}-{0:0}, at: do_coredump+0x1adc/0x2a30 fs/coredump.c:766
 #1: ffff888011b75100 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #1: ffff888011b75100 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ocfs2_file_write_iter+0x46a/0x1f60 fs/ocfs2/file.c:2387
 #2: ffff888011b74da0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_write_begin+0x1d1/0x3a0 fs/ocfs2/aops.c:1901

stack backtrace:
CPU: 0 UID: 0 PID: 5710 Comm: syz.0.18 Not tainted 6.11.0-rc3-syzkaller-00066-g1fb918967b56-dirty #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 ocfs2_get_system_file_inode+0x18f/0x7b0 fs/ocfs2/sysfile.c:101
 ocfs2_reserve_local_alloc_bits+0x107/0x2870 fs/ocfs2/localalloc.c:627
 ocfs2_reserve_clusters_with_limit+0x1b8/0xb60 fs/ocfs2/suballoc.c:1166
 ocfs2_convert_inline_data_to_extents+0x29d/0x17f0 fs/ocfs2/alloc.c:7078
 ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1562 [inline]
 ocfs2_write_begin_nolock+0x1c79/0x4d30 fs/ocfs2/aops.c:1669
 ocfs2_write_begin+0x205/0x3a0 fs/ocfs2/aops.c:1903
 generic_perform_write+0x399/0x840 mm/filemap.c:4019
 ocfs2_file_write_iter+0x17b4/0x1f60 fs/ocfs2/file.c:2455
 __kernel_write_iter+0x40d/0x900 fs/read_write.c:523
 __kernel_write+0x120/0x180 fs/read_write.c:543
 __dump_emit+0x237/0x360 fs/coredump.c:816
 elf_core_dump+0x35e0/0x4720 fs/binfmt_elf.c:2095
 do_coredump+0x1b04/0x2a30 fs/coredump.c:767
 get_signal+0x13fa/0x1740 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f9a89b799c1
Code: 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:ffffffffffffffe0 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f9a89d15f80 RCX: 00007f9a89b799b9
RDX: 0000000000000000 RSI: ffffffffffffffe0 RDI: 0000000004008011
RBP: 00007f9a89be78d8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9a89d15f80 R15: 00007fff4ea50e98
 </TASK>
OCFS2: ERROR (device loop0): int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *, handle_t *, u32, u32, struct ocfs2_suballoc_result *): Chain allocator dinode 23 has 4294967295 used bits but only 16777215 total
On-disk corruption discovered. Please run fsck.ocfs2 once the filesystem is unmounted.
OCFS2: Returning error to the calling process.
(syz.0.18,5710,0):ocfs2_claim_suballoc_bits:2038 ERROR: status = -5
(syz.0.18,5710,0):__ocfs2_claim_clusters:2412 ERROR: status = -5
(syz.0.18,5710,0):__ocfs2_claim_clusters:2420 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_local_alloc_new_window:1197 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_local_alloc_new_window:1222 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_local_alloc_slide_window:1296 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_local_alloc_slide_window:1315 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_reserve_local_alloc_bits:672 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_reserve_local_alloc_bits:710 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_reserve_clusters_with_limit:1170 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_reserve_clusters_with_limit:1219 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_convert_inline_data_to_extents:7080 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_try_to_write_inline_data:1564 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_write_begin_nolock:1676 ERROR: status = -5
(syz.0.18,5710,0):ocfs2_write_begin:1906 ERROR: status = -5
ocfs2: Unmounting device (7,0) on (node local)


Tested on:

commit:         1fb91896 Merge tag 'for-6.11-rc3-tag' of git://git.ker..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=129badf3980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7229118d88b4a71b
dashboard link: https://syzkaller.appspot.com/bug?extid=1fed2de07d8e11a3ec1b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=11e96ea3980000

Re: [syzbot] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org.

***

Subject: possible deadlock in ocfs2_try_remove_refcount_tree
Author: djahchankoike@gmail.com

#syz test

Acquiring the locks in refcounttree should follow
the ip_alloc --> ip_xattr ordering, as done by multiple
code paths in ocfs2; otherwise, we risk an ABBA deadlock
(i.e in the start transaction path).

Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com>
---
 fs/ocfs2/refcounttree.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 1f303b1adf1a..32c0249ff253 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -927,8 +927,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
-	down_write(&oi->ip_xattr_sem);
 	down_write(&oi->ip_alloc_sem);
+	down_write(&oi->ip_xattr_sem);
 
 	if (oi->ip_clusters)
 		goto out;
@@ -944,8 +944,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
 	if (ret)
 		mlog_errno(ret);
 out:
-	up_write(&oi->ip_alloc_sem);
 	up_write(&oi->ip_xattr_sem);
+	up_write(&oi->ip_alloc_sem);
 	return 0;
 }
 
-- 
2.39.2

Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in ocfs2_get_system_file_inode

======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc4-syzkaller-00019-gb311c1b497e5-dirty #0 Not tainted
------------------------------------------------------
syz.0.20/5691 is trying to acquire lock:
ffff8880424195a8 (&osb->system_file_mutex){+.+.}-{3:3}, at: ocfs2_get_system_file_inode+0x18f/0x7b0 fs/ocfs2/sysfile.c:101

but task is already holding lock:
ffff88804e85a2e0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_write_begin+0x1d1/0x3a0 fs/ocfs2/aops.c:1901

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526
       ocfs2_read_virt_blocks+0x2ca/0xa50 fs/ocfs2/extent_map.c:976
       ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
       ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
       ocfs2_find_entry+0x43b/0x2780 fs/ocfs2/dir.c:1080
       ocfs2_find_files_on_disk+0xff/0x360 fs/ocfs2/dir.c:1980
       ocfs2_lookup_ino_from_name+0xb1/0x1e0 fs/ocfs2/dir.c:2002
       _ocfs2_get_system_file_inode fs/ocfs2/sysfile.c:136 [inline]
       ocfs2_get_system_file_inode+0x305/0x7b0 fs/ocfs2/sysfile.c:112
       ocfs2_init_global_system_inodes+0x32c/0x730 fs/ocfs2/super.c:457
       ocfs2_initialize_super fs/ocfs2/super.c:2250 [inline]
       ocfs2_fill_super+0x3068/0x5880 fs/ocfs2/super.c:994
       mount_bdev+0x20a/0x2d0 fs/super.c:1679
       legacy_get_tree+0xee/0x190 fs/fs_context.c:662
       vfs_get_tree+0x90/0x2a0 fs/super.c:1800
       do_new_mount+0x2be/0xb40 fs/namespace.c:3472
       do_mount fs/namespace.c:3812 [inline]
       __do_sys_mount fs/namespace.c:4020 [inline]
       __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&osb->system_file_mutex){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
       __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       ocfs2_get_system_file_inode+0x18f/0x7b0 fs/ocfs2/sysfile.c:101
       ocfs2_reserve_local_alloc_bits+0x107/0x2870 fs/ocfs2/localalloc.c:627
       ocfs2_reserve_clusters_with_limit+0x1b8/0xb60 fs/ocfs2/suballoc.c:1166
       ocfs2_convert_inline_data_to_extents+0x29d/0x17f0 fs/ocfs2/alloc.c:7078
       ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1562 [inline]
       ocfs2_write_begin_nolock+0x1c79/0x4d30 fs/ocfs2/aops.c:1669
       ocfs2_write_begin+0x205/0x3a0 fs/ocfs2/aops.c:1903
       generic_perform_write+0x399/0x840 mm/filemap.c:4019
       ocfs2_file_write_iter+0x17b4/0x1f60 fs/ocfs2/file.c:2455
       __kernel_write_iter+0x40d/0x900 fs/read_write.c:523
       __kernel_write+0x120/0x180 fs/read_write.c:543
       __dump_emit+0x237/0x360 fs/coredump.c:816
       elf_core_dump+0x35e0/0x4720 fs/binfmt_elf.c:2095
       do_coredump+0x1b04/0x2a30 fs/coredump.c:767
       get_signal+0x13fa/0x1740 kernel/signal.c:2902
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
       exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_file_ip_alloc_sem_key);
                               lock(&osb->system_file_mutex);
                               lock(&ocfs2_file_ip_alloc_sem_key);
  lock(&osb->system_file_mutex);

 *** DEADLOCK ***

3 locks held by syz.0.20/5691:
 #0: ffff88804f948420 (sb_writers#12){.+.+}-{0:0}, at: do_coredump+0x1adc/0x2a30 fs/coredump.c:766
 #1: ffff88804e85a640 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #1: ffff88804e85a640 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ocfs2_file_write_iter+0x46a/0x1f60 fs/ocfs2/file.c:2387
 #2: ffff88804e85a2e0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_write_begin+0x1d1/0x3a0 fs/ocfs2/aops.c:1901

stack backtrace:
CPU: 0 UID: 0 PID: 5691 Comm: syz.0.20 Not tainted 6.11.0-rc4-syzkaller-00019-gb311c1b497e5-dirty #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 ocfs2_get_system_file_inode+0x18f/0x7b0 fs/ocfs2/sysfile.c:101
 ocfs2_reserve_local_alloc_bits+0x107/0x2870 fs/ocfs2/localalloc.c:627
 ocfs2_reserve_clusters_with_limit+0x1b8/0xb60 fs/ocfs2/suballoc.c:1166
 ocfs2_convert_inline_data_to_extents+0x29d/0x17f0 fs/ocfs2/alloc.c:7078
 ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1562 [inline]
 ocfs2_write_begin_nolock+0x1c79/0x4d30 fs/ocfs2/aops.c:1669
 ocfs2_write_begin+0x205/0x3a0 fs/ocfs2/aops.c:1903
 generic_perform_write+0x399/0x840 mm/filemap.c:4019
 ocfs2_file_write_iter+0x17b4/0x1f60 fs/ocfs2/file.c:2455
 __kernel_write_iter+0x40d/0x900 fs/read_write.c:523
 __kernel_write+0x120/0x180 fs/read_write.c:543
 __dump_emit+0x237/0x360 fs/coredump.c:816
 elf_core_dump+0x35e0/0x4720 fs/binfmt_elf.c:2095
 do_coredump+0x1b04/0x2a30 fs/coredump.c:767
 get_signal+0x13fa/0x1740 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f58d97799c1
Code: 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:ffffffffffffffe0 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f58d9915f80 RCX: 00007f58d97799b9
RDX: 0000000000000000 RSI: ffffffffffffffe0 RDI: 0000000004008011
RBP: 00007f58d97e78d8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f58d9915f80 R15: 00007ffc8b417b38
 </TASK>
OCFS2: ERROR (device loop0): int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *, handle_t *, u32, u32, struct ocfs2_suballoc_result *): Chain allocator dinode 23 has 4294967295 used bits but only 16777215 total
On-disk corruption discovered. Please run fsck.ocfs2 once the filesystem is unmounted.
OCFS2: Returning error to the calling process.
(syz.0.20,5691,0):ocfs2_claim_suballoc_bits:2038 ERROR: status = -5
(syz.0.20,5691,0):__ocfs2_claim_clusters:2412 ERROR: status = -5
(syz.0.20,5691,0):__ocfs2_claim_clusters:2420 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_local_alloc_new_window:1197 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_local_alloc_new_window:1222 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_local_alloc_slide_window:1296 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_local_alloc_slide_window:1315 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_reserve_local_alloc_bits:672 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_reserve_local_alloc_bits:710 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_reserve_clusters_with_limit:1170 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_reserve_clusters_with_limit:1219 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_convert_inline_data_to_extents:7080 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_try_to_write_inline_data:1564 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_write_begin_nolock:1676 ERROR: status = -5
(syz.0.20,5691,0):ocfs2_write_begin:1906 ERROR: status = -5
ocfs2: Unmounting device (7,0) on (node local)


Tested on:

commit:         b311c1b4 Merge tag '6.11-rc4-server-fixes' of git://gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16dfa42b980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=df2f0ed7e30a639d
dashboard link: https://syzkaller.appspot.com/bug?extid=1fed2de07d8e11a3ec1b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=178f93d5980000

Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

syzbot has bisected this issue to:

commit a3c06ae158dd6fa8336157c31d9234689d068d02
Author: Parav Pandit <parav@nvidia.com>
Date:   Tue Jan 5 10:32:03 2021 +0000

    vdpa_sim_net: Add support for user supported devices

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=11f6ca27980000
start commit:   de5cb0dcb74c Merge branch 'address-masking'
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=13f6ca27980000
console output: https://syzkaller.appspot.com/x/log.txt?x=15f6ca27980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=74ffdb3b3fad1a43
dashboard link: https://syzkaller.appspot.com/bug?extid=1fed2de07d8e11a3ec1b
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12f23880580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15851c27980000

Reported-by: syzbot+1fed2de07d8e11a3ec1b@syzkaller.appspotmail.com
Fixes: a3c06ae158dd ("vdpa_sim_net: Add support for user supported devices")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[Tetsuo Handa]

#syz test

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 6aaa94c554c1..8bdeea60742a 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -494,8 +494,6 @@ struct ocfs2_super
 	struct rb_root	osb_rf_lock_tree;
 	struct ocfs2_refcount_tree *osb_ref_tree_lru;
 
-	struct mutex system_file_mutex;
-
 	/*
 	 * OCFS2 needs to schedule several different types of work which
 	 * require cluster locking, disk I/O, recovery waits, etc. Since these
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 8f732742b26e..c8467b92b64e 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -928,8 +928,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
-	down_write(&oi->ip_xattr_sem);
 	down_write(&oi->ip_alloc_sem);
+	down_write(&oi->ip_xattr_sem);
 
 	if (oi->ip_clusters)
 		goto out;
@@ -945,8 +945,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
 	if (ret)
 		mlog_errno(ret);
 out:
-	up_write(&oi->ip_alloc_sem);
 	up_write(&oi->ip_xattr_sem);
+	up_write(&oi->ip_alloc_sem);
 	return 0;
 }
 
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 3d2533950bae..4461daf909cf 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1997,8 +1997,6 @@ static int ocfs2_initialize_super(struct super_block *sb,
 	spin_lock_init(&osb->osb_xattr_lock);
 	ocfs2_init_steal_slots(osb);
 
-	mutex_init(&osb->system_file_mutex);
-
 	atomic_set(&osb->alloc_stats.moves, 0);
 	atomic_set(&osb->alloc_stats.local_data, 0);
 	atomic_set(&osb->alloc_stats.bitmap_data, 0);
diff --git a/fs/ocfs2/sysfile.c b/fs/ocfs2/sysfile.c
index 53a945da873b..03e7a0cd55aa 100644
--- a/fs/ocfs2/sysfile.c
+++ b/fs/ocfs2/sysfile.c
@@ -98,11 +98,9 @@ struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
 	} else
 		arr = get_local_system_inode(osb, type, slot);
 
-	mutex_lock(&osb->system_file_mutex);
 	if (arr && ((inode = *arr) != NULL)) {
 		/* get a ref in addition to the array ref */
 		inode = igrab(inode);
-		mutex_unlock(&osb->system_file_mutex);
 		BUG_ON(!inode);
 
 		return inode;
@@ -112,11 +110,8 @@ struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
 	inode = _ocfs2_get_system_file_inode(osb, type, slot);
 
 	/* add one more if putting into array for first time */
-	if (arr && inode) {
-		*arr = igrab(inode);
-		BUG_ON(!*arr);
-	}
-	mutex_unlock(&osb->system_file_mutex);
+	if (inode && arr && !*arr && !cmpxchg(&(*arr), NULL, inode))
+		igrab(*arr);
 	return inode;
 }
 

Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+1fed2de07d8e11a3ec1b@syzkaller.appspotmail.com
Tested-by: syzbot+1fed2de07d8e11a3ec1b@syzkaller.appspotmail.com

Tested on:

commit:         3f75bfff Merge tag 'mtd/fixes-for-6.16-rc3' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1730f30c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6a237c32900fc479
dashboard link: https://syzkaller.appspot.com/bug?extid=1fed2de07d8e11a3ec1b
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
patch:          https://syzkaller.appspot.com/x/patch.diff?x=158ac182580000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] possible deadlock in ocfs2_try_remove_refcount_tree

[Tetsuo Handa]

Please re-submit this change as a formal patch.
You can add

  Reported-by: syzbot+1fed2de07d8e11a3ec1b@syzkaller.appspotmail.com
  Tested-by: syzbot+1fed2de07d8e11a3ec1b@syzkaller.appspotmail.com

lines to this change.

On 2024/08/22 6:04, syzbot wrote:
> For archival purposes, forwarding an incoming command email to
> linux-kernel@vger.kernel.org.
> 
> ***
> 
> Subject: possible deadlock in ocfs2_try_remove_refcount_tree
> Author: djahchankoike@gmail.com
> 
> #syz test
> 
> Acquiring the locks in refcounttree should follow
> the ip_alloc --> ip_xattr ordering, as done by multiple
> code paths in ocfs2; otherwise, we risk an ABBA deadlock
> (i.e in the start transaction path).
> 
> Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com>
> ---
>  fs/ocfs2/refcounttree.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
> index 1f303b1adf1a..32c0249ff253 100644
> --- a/fs/ocfs2/refcounttree.c
> +++ b/fs/ocfs2/refcounttree.c
> @@ -927,8 +927,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
>  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
>  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
>  
> -	down_write(&oi->ip_xattr_sem);
>  	down_write(&oi->ip_alloc_sem);
> +	down_write(&oi->ip_xattr_sem);
>  
>  	if (oi->ip_clusters)
>  		goto out;
> @@ -944,8 +944,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
>  	if (ret)
>  		mlog_errno(ret);
>  out:
> -	up_write(&oi->ip_alloc_sem);
>  	up_write(&oi->ip_xattr_sem);
> +	up_write(&oi->ip_alloc_sem);
>  	return 0;
>  }
>  

Re: [syzbot] possible deadlock in ocfs2_try_remove_refcount_tree

[Tetsuo Handa]

Please submit as a formal patch. You can add

Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

tag.

On 2024/08/22 6:04, syzbot wrote:
> For archival purposes, forwarding an incoming command email to
> linux-kernel@vger.kernel.org.
> 
> ***
> 
> Subject: possible deadlock in ocfs2_try_remove_refcount_tree
> Author: djahchankoike@gmail.com
> 
> #syz test
> 
> Acquiring the locks in refcounttree should follow
> the ip_alloc --> ip_xattr ordering, as done by multiple
> code paths in ocfs2; otherwise, we risk an ABBA deadlock
> (i.e in the start transaction path).
> 
> Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com>
> ---
>  fs/ocfs2/refcounttree.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
> index 1f303b1adf1a..32c0249ff253 100644
> --- a/fs/ocfs2/refcounttree.c
> +++ b/fs/ocfs2/refcounttree.c
> @@ -927,8 +927,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
>  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
>  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
>  
> -	down_write(&oi->ip_xattr_sem);
>  	down_write(&oi->ip_alloc_sem);
> +	down_write(&oi->ip_xattr_sem);
>  
>  	if (oi->ip_clusters)
>  		goto out;
> @@ -944,8 +944,8 @@ int ocfs2_try_remove_refcount_tree(struct inode *inode,
>  	if (ret)
>  		mlog_errno(ret);
>  out:
> -	up_write(&oi->ip_alloc_sem);
>  	up_write(&oi->ip_xattr_sem);
> +	up_write(&oi->ip_alloc_sem);
>  	return 0;
>  }
>  

Forwarded: Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree
Author: penguin-kernel@i-love.sakura.ne.jp

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_remove_refcount_tree

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in ocfs2_truncate_file

         option from the mount to silence this warning.
=======================================================
ocfs2: Mounting device (7,0) on (node local, slot 0) with writeback data mode.
======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc6-syzkaller-00253-g4871b7cb27f4-dirty #0 Not tainted
------------------------------------------------------
syz.0.16/6592 is trying to acquire lock:
ffff88807a9fc618 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_orphan_for_truncate fs/ocfs2/file.c:396 [inline]
ffff88807a9fc618 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_truncate_file+0x648/0x1410 fs/ocfs2/file.c:500

but task is already holding lock:
ffff88807da38660 (&oi->ip_alloc_sem){++++}-{4:4}, at: ocfs2_down_write fs/ocfs2/inode.h:74 [inline]
ffff88807da38660 (&oi->ip_alloc_sem){++++}-{4:4}, at: ocfs2_truncate_file+0x36a/0x1410 fs/ocfs2/file.c:471

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&oi->ip_alloc_sem){++++}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577
       ocfs2_down_write fs/ocfs2/inode.h:74 [inline]
       ocfs2_xattr_set_handle+0x3af/0x7a0 fs/ocfs2/xattr.c:3503
       ocfs2_init_security_set+0xbd/0xe0 fs/ocfs2/xattr.c:7309
       ocfs2_mknod+0x137f/0x2050 fs/ocfs2/namei.c:419
       ocfs2_create+0x1a5/0x440 fs/ocfs2/namei.c:673
       lookup_open fs/namei.c:3717 [inline]
       open_last_lookups fs/namei.c:3816 [inline]
       path_openat+0x14f1/0x3830 fs/namei.c:4052
       do_filp_open+0x1fa/0x410 fs/namei.c:4082
       do_sys_openat2+0x121/0x1c0 fs/open.c:1437
       do_sys_open fs/open.c:1452 [inline]
       __do_sys_open fs/open.c:1460 [inline]
       __se_sys_open fs/open.c:1456 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1456
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #3 (&oi->ip_xattr_sem){++++}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577
       ocfs2_down_write fs/ocfs2/inode.h:73 [inline]
       ocfs2_xattr_set_handle+0x3a0/0x7a0 fs/ocfs2/xattr.c:3503
       ocfs2_init_security_set+0xbd/0xe0 fs/ocfs2/xattr.c:7309
       ocfs2_mknod+0x137f/0x2050 fs/ocfs2/namei.c:419
       ocfs2_create+0x1a5/0x440 fs/ocfs2/namei.c:673
       lookup_open fs/namei.c:3717 [inline]
       open_last_lookups fs/namei.c:3816 [inline]
       path_openat+0x14f1/0x3830 fs/namei.c:4052
       do_filp_open+0x1fa/0x410 fs/namei.c:4082
       do_sys_openat2+0x121/0x1c0 fs/open.c:1437
       do_sys_open fs/open.c:1452 [inline]
       __do_sys_open fs/open.c:1460 [inline]
       __se_sys_open fs/open.c:1456 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1456
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (jbd2_handle){++++}-{0:0}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       start_this_handle+0x1fa7/0x21c0 fs/jbd2/transaction.c:444
       jbd2__journal_start+0x2c1/0x5b0 fs/jbd2/transaction.c:501
       jbd2_journal_start+0x2a/0x40 fs/jbd2/transaction.c:540
       ocfs2_start_trans+0x376/0x6d0 fs/ocfs2/journal.c:374
       ocfs2_block_group_alloc fs/ocfs2/suballoc.c:685 [inline]
       ocfs2_reserve_suballoc_bits+0x711/0x4640 fs/ocfs2/suballoc.c:834
       ocfs2_reserve_new_metadata_blocks+0x403/0x940 fs/ocfs2/suballoc.c:984
       ocfs2_mknod+0xe08/0x2050 fs/ocfs2/namei.c:347
       ocfs2_create+0x1a5/0x440 fs/ocfs2/namei.c:673
       lookup_open fs/namei.c:3717 [inline]
       open_last_lookups fs/namei.c:3816 [inline]
       path_openat+0x14f1/0x3830 fs/namei.c:4052
       do_filp_open+0x1fa/0x410 fs/namei.c:4082
       do_sys_openat2+0x121/0x1c0 fs/open.c:1437
       do_sys_open fs/open.c:1452 [inline]
       __do_sys_open fs/open.c:1460 [inline]
       __se_sys_open fs/open.c:1456 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1456
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&journal->j_trans_barrier){.+.+}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       down_read+0x46/0x2e0 kernel/locking/rwsem.c:1524
       ocfs2_start_trans+0x36a/0x6d0 fs/ocfs2/journal.c:372
       ocfs2_block_group_alloc fs/ocfs2/suballoc.c:685 [inline]
       ocfs2_reserve_suballoc_bits+0x711/0x4640 fs/ocfs2/suballoc.c:834
       ocfs2_reserve_new_metadata_blocks+0x403/0x940 fs/ocfs2/suballoc.c:984
       ocfs2_mknod+0xe08/0x2050 fs/ocfs2/namei.c:347
       ocfs2_create+0x1a5/0x440 fs/ocfs2/namei.c:673
       lookup_open fs/namei.c:3717 [inline]
       open_last_lookups fs/namei.c:3816 [inline]
       path_openat+0x14f1/0x3830 fs/namei.c:4052
       do_filp_open+0x1fa/0x410 fs/namei.c:4082
       do_sys_openat2+0x121/0x1c0 fs/open.c:1437
       do_sys_open fs/open.c:1452 [inline]
       __do_sys_open fs/open.c:1460 [inline]
       __se_sys_open fs/open.c:1456 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1456
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sb_internal#2){.+.+}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3168 [inline]
       check_prevs_add kernel/locking/lockdep.c:3287 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
       __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs.h:1795 [inline]
       sb_start_intwrite include/linux/fs.h:1978 [inline]
       ocfs2_start_trans+0x26b/0x6d0 fs/ocfs2/journal.c:370
       ocfs2_orphan_for_truncate fs/ocfs2/file.c:396 [inline]
       ocfs2_truncate_file+0x648/0x1410 fs/ocfs2/file.c:500
       ocfs2_setattr+0x1571/0x1b60 fs/ocfs2/file.c:1212
       notify_change+0xb36/0xe40 fs/attr.c:552
       do_truncate+0x1a4/0x220 fs/open.c:68
       handle_truncate fs/namei.c:3517 [inline]
       do_open fs/namei.c:3900 [inline]
       path_openat+0x306c/0x3830 fs/namei.c:4055
       do_filp_open+0x1fa/0x410 fs/namei.c:4082
       do_sys_openat2+0x121/0x1c0 fs/open.c:1437
       do_sys_open fs/open.c:1452 [inline]
       __do_sys_open fs/open.c:1460 [inline]
       __se_sys_open fs/open.c:1456 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1456
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  sb_internal#2 --> &oi->ip_xattr_sem --> &oi->ip_alloc_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_alloc_sem);
                               lock(&oi->ip_xattr_sem);
                               lock(&oi->ip_alloc_sem);
  rlock(sb_internal#2);

 *** DEADLOCK ***

4 locks held by syz.0.16/6592:
 #0: ffff88807a9fc428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
 #1: ffff88807da389c0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:874 [inline]
 #1: ffff88807da389c0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: do_truncate+0x171/0x220 fs/open.c:63
 #2: ffff88807da386f8 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_down_write fs/ocfs2/inode.h:73 [inline]
 #2: ffff88807da386f8 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_truncate_file+0x359/0x1410 fs/ocfs2/file.c:471
 #3: ffff88807da38660 (&oi->ip_alloc_sem){++++}-{4:4}, at: ocfs2_down_write fs/ocfs2/inode.h:74 [inline]
 #3: ffff88807da38660 (&oi->ip_alloc_sem){++++}-{4:4}, at: ocfs2_truncate_file+0x36a/0x1410 fs/ocfs2/file.c:471

stack backtrace:
CPU: 1 UID: 0 PID: 6592 Comm: syz.0.16 Not tainted 6.16.0-rc6-syzkaller-00253-g4871b7cb27f4-dirty #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3168 [inline]
 check_prevs_add kernel/locking/lockdep.c:3287 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
 percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
 __sb_start_write include/linux/fs.h:1795 [inline]
 sb_start_intwrite include/linux/fs.h:1978 [inline]
 ocfs2_start_trans+0x26b/0x6d0 fs/ocfs2/journal.c:370
 ocfs2_orphan_for_truncate fs/ocfs2/file.c:396 [inline]
 ocfs2_truncate_file+0x648/0x1410 fs/ocfs2/file.c:500
 ocfs2_setattr+0x1571/0x1b60 fs/ocfs2/file.c:1212
 notify_change+0xb36/0xe40 fs/attr.c:552
 do_truncate+0x1a4/0x220 fs/open.c:68
 handle_truncate fs/namei.c:3517 [inline]
 do_open fs/namei.c:3900 [inline]
 path_openat+0x306c/0x3830 fs/namei.c:4055
 do_filp_open+0x1fa/0x410 fs/namei.c:4082
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_open fs/open.c:1460 [inline]
 __se_sys_open fs/open.c:1456 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1456
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa61778e929
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:00007fa61868b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fa6179b5fa0 RCX: 00007fa61778e929
RDX: 0000000000000020 RSI: 000000000014927e RDI: 00002000000001c0
RBP: 00007fa617810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa6179b5fa0 R15: 00007fffb0c2bbe8
 </TASK>


Tested on:

commit:         4871b7cb Merge tag 'v6.16-rc6-smb3-client-fixes' of gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1474c38c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f09d04131ef56b22
dashboard link: https://syzkaller.appspot.com/bug?extid=1fed2de07d8e11a3ec1b
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1510c38c580000