[syzbot] [jfs?] possible deadlock in jfs_mount_rw

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dbe0a7be2838 Merge tag 'thermal-6.9-rc5' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11253abf180000
kernel config: https://syzkaller.appspot.com/x/.config?x=2dc5adfa93a8cfac
dashboard link: https://syzkaller.appspot.com/bug?extid=1bd2671092cc9e4d4fef
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-dbe0a7be.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7a1028fc6c27/vmlinux-dbe0a7be.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d129fb5bb25f/bzImage-dbe0a7be.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1bd267...@syzkaller.appspotmail.com

... Log Wrap ... Log Wrap ... Log Wrap ...
... Log Wrap ... Log Wrap ... Log Wrap ...
======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc4-syzkaller-00164-gdbe0a7be2838 #0 Not tainted
------------------------------------------------------
syz-executor.2/8572 is trying to acquire lock:
ffffffff8d9373c0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:312 [inline]
ffffffff8d9373c0 (fs_reclaim){+.+.}-{0:0}, at: prepare_alloc_pages.constprop.0+0x155/0x560 mm/page_alloc.c:4346

but task is already holding lock:
ffff8880282e2638 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: jfs_mount_rw+0x1eb/0x700 fs/jfs/jfs_mount.c:238

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&jfs_ip->rdwrlock/1){++++}-{3:3}:
down_read_nested+0x9e/0x330 kernel/locking/rwsem.c:1651
diAlloc+0x3ea/0x1a70 fs/jfs/jfs_imap.c:1385
ialloc+0x84/0x9e0 fs/jfs/jfs_inode.c:56
jfs_symlink+0x277/0x1140 fs/jfs/namei.c:917
vfs_symlink fs/namei.c:4481 [inline]
vfs_symlink+0x3e8/0x630 fs/namei.c:4465
do_symlinkat+0x263/0x310 fs/namei.c:4507
__do_sys_symlinkat fs/namei.c:4523 [inline]
__se_sys_symlinkat fs/namei.c:4520 [inline]
__ia32_sys_symlinkat+0x97/0xc0 fs/namei.c:4520
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:321
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346
entry_SYSENTER_compat_after_hwframe+0x84/0x8e

-> #1 (&(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+0x295/0x440 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:4774
shrink_many mm/vmscan.c:4835 [inline]
lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935
shrink_node mm/vmscan.c:5894 [inline]
kswapd_shrink_node mm/vmscan.c:6704 [inline]
balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895
kswapd+0x5ea/0xbf0 mm/vmscan.c:7164
kthread+0x2c1/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #0 (fs_reclaim){+.+.}-{0:0}:
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
__fs_reclaim_acquire mm/page_alloc.c:3698 [inline]
fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712
might_alloc include/linux/sched/mm.h:312 [inline]
prepare_alloc_pages.constprop.0+0x155/0x560 mm/page_alloc.c:4346
__alloc_pages+0x194/0x2460 mm/page_alloc.c:4564
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
__kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
kmalloc_large+0x1c/0x70 mm/slub.c:3928
kmalloc include/linux/slab.h:625 [inline]
diMount+0x29/0x8d0 fs/jfs/jfs_imap.c:105
jfs_mount_rw+0x238/0x700 fs/jfs/jfs_mount.c:240
jfs_remount+0x51f/0x650 fs/jfs/super.c:454
legacy_reconfigure+0x119/0x180 fs/fs_context.c:685
reconfigure_super+0x44f/0xb20 fs/super.c:1071
vfs_cmd_reconfigure fs/fsopen.c:267 [inline]
vfs_fsconfig_locked fs/fsopen.c:296 [inline]
__do_sys_fsconfig+0x991/0xb90 fs/fsopen.c:476
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:321
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346
entry_SYSENTER_compat_after_hwframe+0x84/0x8e

other info that might help us debug this:

Chain exists of:
fs_reclaim --> &(imap->im_aglock[index]) --> &jfs_ip->rdwrlock/1

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&jfs_ip->rdwrlock/1);
lock(&(imap->im_aglock[index]));
lock(&jfs_ip->rdwrlock/1);
lock(fs_reclaim);

*** DEADLOCK ***

3 locks held by syz-executor.2/8572:
#0: ffff8880264b1c70 (&fc->uapi_mutex){+.+.}-{3:3}, at: __do_sys_fsconfig+0x7d4/0xb90 fs/fsopen.c:474
#1: ffff888015ff40e0 (&type->s_umount_key#67){++++}-{3:3}, at: vfs_cmd_reconfigure fs/fsopen.c:266 [inline]
#1: ffff888015ff40e0 (&type->s_umount_key#67){++++}-{3:3}, at: vfs_fsconfig_locked fs/fsopen.c:296 [inline]
#1: ffff888015ff40e0 (&type->s_umount_key#67){++++}-{3:3}, at: __do_sys_fsconfig+0x987/0xb90 fs/fsopen.c:476
#2: ffff8880282e2638 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: jfs_mount_rw+0x1eb/0x700 fs/jfs/jfs_mount.c:238

stack backtrace:
CPU: 3 PID: 8572 Comm: syz-executor.2 Not tainted 6.9.0-rc4-syzkaller-00164-gdbe0a7be2838 #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
__fs_reclaim_acquire mm/page_alloc.c:3698 [inline]
fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712
might_alloc include/linux/sched/mm.h:312 [inline]
prepare_alloc_pages.constprop.0+0x155/0x560 mm/page_alloc.c:4346
__alloc_pages+0x194/0x2460 mm/page_alloc.c:4564
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
__kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
kmalloc_large+0x1c/0x70 mm/slub.c:3928
kmalloc include/linux/slab.h:625 [inline]
diMount+0x29/0x8d0 fs/jfs/jfs_imap.c:105
jfs_mount_rw+0x238/0x700 fs/jfs/jfs_mount.c:240
jfs_remount+0x51f/0x650 fs/jfs/super.c:454
legacy_reconfigure+0x119/0x180 fs/fs_context.c:685
reconfigure_super+0x44f/0xb20 fs/super.c:1071
vfs_cmd_reconfigure fs/fsopen.c:267 [inline]
vfs_fsconfig_locked fs/fsopen.c:296 [inline]
__do_sys_fsconfig+0x991/0xb90 fs/fsopen.c:476
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:321
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7324579
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:00000000f5f165ac EFLAGS: 00000292 ORIG_RAX: 00000000000001af
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>

... Log Wrap ... Log Wrap ... Log Wrap ...

----------------
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


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