[syzbot] possible deadlock in hfsplus_file_truncate

From: syzbot
Date: Sat Nov 26 2022 - 03:08:12 EST

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Hello,

syzbot found the following issue on:

HEAD commit: 08ad43d554ba Merge tag 'net-6.1-rc7' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11da779b880000
kernel config: https://syzkaller.appspot.com/x/.config?x=8d01b6e3197974dd
dashboard link: https://syzkaller.appspot.com/bug?extid=6030b3b1b9bf70e538c4
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e40e255b7cf8/disk-08ad43d5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dfabe238c5ee/vmlinux-08ad43d5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2bcb24a7bbed/bzImage-08ad43d5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6030b3b1b9bf70e538c4@xxxxxxxxxxxxxxxxxxxxxxxxx

loop4: detected capacity change from 0 to 1024
======================================================
WARNING: possible circular locking dependency detected
6.1.0-rc6-syzkaller-00176-g08ad43d554ba #0 Not tainted
------------------------------------------------------
syz-executor.4/25725 is trying to acquire lock:
ffff888146b700b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x871/0xbb0 fs/hfsplus/extents.c:595

but task is already holding lock:
ffff888029f69c08 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x280/0xbb0 fs/hfsplus/extents.c:576

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}:
lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668
__mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
hfsplus_file_extend+0x1af/0x19d0 fs/hfsplus/extents.c:457
hfsplus_bmap_reserve+0x123/0x500 fs/hfsplus/btree.c:358
hfsplus_create_cat+0x178/0xa20 fs/hfsplus/catalog.c:272
hfsplus_fill_super+0x1379/0x1b50 fs/hfsplus/super.c:560
mount_bdev+0x26c/0x3a0 fs/super.c:1401
legacy_get_tree+0xea/0x180 fs/fs_context.c:610
vfs_get_tree+0x88/0x270 fs/super.c:1531
do_new_mount+0x289/0xad0 fs/namespace.c:3040
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&tree->tree_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain+0x1898/0x6ae0 kernel/locking/lockdep.c:3831
__lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055
lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668
__mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
hfsplus_file_truncate+0x871/0xbb0 fs/hfsplus/extents.c:595
hfsplus_setattr+0x1b8/0x280 fs/hfsplus/inode.c:269
notify_change+0xe38/0x10f0 fs/attr.c:420
do_truncate+0x1fb/0x2e0 fs/open.c:65
handle_truncate fs/namei.c:3216 [inline]
do_open fs/namei.c:3561 [inline]
path_openat+0x2770/0x2df0 fs/namei.c:3713
do_filp_open+0x264/0x4f0 fs/namei.c:3740
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_creat fs/open.c:1402 [inline]
__se_sys_creat fs/open.c:1396 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1396
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&HFSPLUS_I(inode)->extents_lock);
lock(&tree->tree_lock);
lock(&HFSPLUS_I(inode)->extents_lock);
lock(&tree->tree_lock);

*** DEADLOCK ***

3 locks held by syz-executor.4/25725:
#0: ffff888146b76460 (sb_writers#29){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
#1: ffff888029f69e00 (&sb->s_type->i_mutex_key#36){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff888029f69e00 (&sb->s_type->i_mutex_key#36){+.+.}-{3:3}, at: do_truncate+0x1e7/0x2e0 fs/open.c:63
#2: ffff888029f69c08 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x280/0xbb0 fs/hfsplus/extents.c:576

stack backtrace:
CPU: 0 PID: 25725 Comm: syz-executor.4 Not tainted 6.1.0-rc6-syzkaller-00176-g08ad43d554ba #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2177
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain+0x1898/0x6ae0 kernel/locking/lockdep.c:3831
__lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055
lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668
__mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
hfsplus_file_truncate+0x871/0xbb0 fs/hfsplus/extents.c:595
hfsplus_setattr+0x1b8/0x280 fs/hfsplus/inode.c:269
notify_change+0xe38/0x10f0 fs/attr.c:420
do_truncate+0x1fb/0x2e0 fs/open.c:65
handle_truncate fs/namei.c:3216 [inline]
do_open fs/namei.c:3561 [inline]
path_openat+0x2770/0x2df0 fs/namei.c:3713
do_filp_open+0x264/0x4f0 fs/namei.c:3740
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_creat fs/open.c:1402 [inline]
__se_sys_creat fs/open.c:1396 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1396
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe76648c0d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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
RSP: 002b:00007fe767238168 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fe7665abf80 RCX: 00007fe76648c0d9
RDX: 0000000000000000 RSI: 00000000000000b8 RDI: 0000000020000100
RBP: 00007fe7664e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffef191c68f R14: 00007fe767238300 R15: 0000000000022000
</TASK>

---
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