Re: [syzbot] [ntfs3?] possible deadlock in ntfs_set_state (2)

From: syzbot
Date: Tue Feb 13 2024 - 06:10:10 EST


Hello,

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

loop0: detected capacity change from 0 to 4096
ntfs3: loop0: Different NTFS sector size (4096) and media sector size (512).
ntfs3: loop0: ino=5, "/" ntfs_iget5
============================================
WARNING: possible recursive locking detected
6.8.0-rc4-syzkaller-00005-gc664e16bb1ba-dirty #0 Not tainted
--------------------------------------------
syz-executor.0/5514 is trying to acquire lock:
ffff888068bf8100 (&ni->ni_lock#3){+.+.}-{3:3}, at: ntfs_set_state+0x1ff/0x6c0 fs/ntfs3/fsntfs.c:947

but task is already holding lock:
ffff888068bf9e80 (&ni->ni_lock#3){+.+.}-{3:3}, at: ni_trylock fs/ntfs3/ntfs_fs.h:1141 [inline]
ffff888068bf9e80 (&ni->ni_lock#3){+.+.}-{3:3}, at: ni_write_inode+0x1bc/0x1010 fs/ntfs3/frecord.c:3264

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

CPU0
----
lock(&ni->ni_lock#3);
lock(&ni->ni_lock#3);

*** DEADLOCK ***

May be due to missing lock nesting notation

3 locks held by syz-executor.0/5514:
#0: ffff88802ec00420 (sb_writers#13){.+.+}-{0:0}, at: do_sys_ftruncate+0x25c/0x390 fs/open.c:191
#1: ffff888068bfa120 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline]
#1: ffff888068bfa120 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:64
#2: ffff888068bf9e80 (&ni->ni_lock#3){+.+.}-{3:3}, at: ni_trylock fs/ntfs3/ntfs_fs.h:1141 [inline]
#2: ffff888068bf9e80 (&ni->ni_lock#3){+.+.}-{3:3}, at: ni_write_inode+0x1bc/0x1010 fs/ntfs3/frecord.c:3264

stack backtrace:
CPU: 0 PID: 5514 Comm: syz-executor.0 Not tainted 6.8.0-rc4-syzkaller-00005-gc664e16bb1ba-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
check_deadlock kernel/locking/lockdep.c:3062 [inline]
validate_chain+0x15c0/0x58e0 kernel/locking/lockdep.c:3856
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
ntfs_set_state+0x1ff/0x6c0 fs/ntfs3/fsntfs.c:947
ntfs_iget5+0x3f0/0x3b70 fs/ntfs3/inode.c:535
ni_update_parent+0x934/0xdc0 fs/ntfs3/frecord.c:3217
ni_write_inode+0xde9/0x1010 fs/ntfs3/frecord.c:3323
ntfs_truncate fs/ntfs3/file.c:410 [inline]
ntfs3_setattr+0x950/0xb40 fs/ntfs3/file.c:703
notify_change+0xb9f/0xe70 fs/attr.c:499
do_truncate+0x220/0x310 fs/open.c:66
do_sys_ftruncate+0x2f7/0x390 fs/open.c:194
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f8b46a7dda9
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:00007f8b478530c8 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f8b46babf80 RCX: 00007f8b46a7dda9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f8b46aca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f8b46babf80 R15: 00007ffcddaf9d18
</TASK>
ntfs3: loop0: Mark volume as dirty due to NTFS errors


Tested on:

commit: c664e16b Merge tag 'docs-6.8-fixes2' of git://git.lwn...
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=152c5114180000
kernel config: https://syzkaller.appspot.com/x/.config?x=1d7c92dd8d5c7a1e
dashboard link: https://syzkaller.appspot.com/bug?extid=c2ada45c23d98d646118
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=15ff6de0180000