* [syzbot] [exfat?] possible deadlock in exfat_iterate (2)
@ 2024-06-27 12:58 syzbot
2024-06-27 23:13 ` Namjae Jeon
0 siblings, 1 reply; 3+ messages in thread
From: syzbot @ 2024-06-27 12:58 UTC (permalink / raw)
To: linkinjeon, linux-fsdevel, linux-kernel, sj1557.seo,
syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: 55027e689933 Merge tag 'input-for-v6.10-rc5' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16390ac1980000
kernel config: https://syzkaller.appspot.com/x/.config?x=53ab35b556129242
dashboard link: https://syzkaller.appspot.com/bug?extid=df3558df41609451e4ac
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-55027e68.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a36929b5a065/vmlinux-55027e68.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d72de6f61ddc/bzImage-55027e68.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+df3558df41609451e4ac@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc5-syzkaller-00018-g55027e689933 #0 Not tainted
------------------------------------------------------
syz-executor.2/6265 is trying to acquire lock:
ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: __do_kmalloc_node mm/slub.c:4121 [inline]
ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_noprof+0xb5/0x420 mm/slub.c:4135
but task is already holding lock:
ffff88804af1a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x33f/0xad0 fs/exfat/dir.c:256
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&sbi->s_lock#2){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
exfat_evict_inode+0x25b/0x340 fs/exfat/inode.c:725
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
-> #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: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]
kmalloc_array_noprof include/linux/slab.h:699 [inline]
__exfat_get_dentry_set+0x81e/0xa90 fs/exfat/dir.c:816
exfat_get_dentry_set+0x36/0x210 fs/exfat/dir.c:859
exfat_get_uniname_from_ext_entry fs/exfat/dir.c:39 [inline]
exfat_readdir+0x950/0x1520 fs/exfat/dir.c:155
exfat_iterate+0x3c7/0xad0 fs/exfat/dir.c:261
wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
iterate_dir+0x53e/0xb60 fs/readdir.c:110
__do_sys_getdents64 fs/readdir.c:409 [inline]
__se_sys_getdents64 fs/readdir.c:394 [inline]
__ia32_sys_getdents64+0x14f/0x2e0 fs/readdir.c:394
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:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sbi->s_lock#2);
lock(fs_reclaim);
lock(&sbi->s_lock#2);
lock(fs_reclaim);
*** DEADLOCK ***
3 locks held by syz-executor.2/6265:
#0: ffff88801db114c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191
#1: ffff8880483da9e8 (&sb->s_type->i_mutex_key#24){++++}-{3:3}, at: wrap_directory_iterator+0x5a/0xe0 fs/readdir.c:56
#2: ffff88804af1a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x33f/0xad0 fs/exfat/dir.c:256
stack backtrace:
CPU: 0 PID: 6265 Comm: syz-executor.2 Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #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: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]
kmalloc_array_noprof include/linux/slab.h:699 [inline]
__exfat_get_dentry_set+0x81e/0xa90 fs/exfat/dir.c:816
exfat_get_dentry_set+0x36/0x210 fs/exfat/dir.c:859
exfat_get_uniname_from_ext_entry fs/exfat/dir.c:39 [inline]
exfat_readdir+0x950/0x1520 fs/exfat/dir.c:155
exfat_iterate+0x3c7/0xad0 fs/exfat/dir.c:261
wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
iterate_dir+0x53e/0xb60 fs/readdir.c:110
__do_sys_getdents64 fs/readdir.c:409 [inline]
__se_sys_getdents64 fs/readdir.c:394 [inline]
__ia32_sys_getdents64+0x14f/0x2e0 fs/readdir.c:394
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: 0023:0xf72f8579
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:00000000f5ec95ac EFLAGS: 00000292 ORIG_RAX: 00000000000000dc
RAX: ffffffffffffffda RBX: 000000000000000a RCX: 0000000020002ec0
RDX: 0000000000001000 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
---
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syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
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If you want to undo deduplication, reply with:
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [exfat?] possible deadlock in exfat_iterate (2)
2024-06-27 12:58 [syzbot] [exfat?] possible deadlock in exfat_iterate (2) syzbot
@ 2024-06-27 23:13 ` Namjae Jeon
2024-06-27 23:13 ` syzbot
0 siblings, 1 reply; 3+ messages in thread
From: Namjae Jeon @ 2024-06-27 23:13 UTC (permalink / raw)
To: syzbot; +Cc: linux-fsdevel, linux-kernel, sj1557.seo, syzkaller-bugs
#syz test git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat.git dev
2024년 6월 27일 (목) 오후 9:58, syzbot
<syzbot+df3558df41609451e4ac@syzkaller.appspotmail.com>님이 작성:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 55027e689933 Merge tag 'input-for-v6.10-rc5' of git://git...
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16390ac1980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=53ab35b556129242
> dashboard link: https://syzkaller.appspot.com/bug?extid=df3558df41609451e4ac
> 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-55027e68.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/a36929b5a065/vmlinux-55027e68.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/d72de6f61ddc/bzImage-55027e68.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+df3558df41609451e4ac@syzkaller.appspotmail.com
>
> ======================================================
> WARNING: possible circular locking dependency detected
> 6.10.0-rc5-syzkaller-00018-g55027e689933 #0 Not tainted
> ------------------------------------------------------
> syz-executor.2/6265 is trying to acquire lock:
> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: __do_kmalloc_node mm/slub.c:4121 [inline]
> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_noprof+0xb5/0x420 mm/slub.c:4135
>
> but task is already holding lock:
> ffff88804af1a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x33f/0xad0 fs/exfat/dir.c:256
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #1 (&sbi->s_lock#2){+.+.}-{3:3}:
> __mutex_lock_common kernel/locking/mutex.c:608 [inline]
> __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
> exfat_evict_inode+0x25b/0x340 fs/exfat/inode.c:725
> 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
>
> -> #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: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]
> kmalloc_array_noprof include/linux/slab.h:699 [inline]
> __exfat_get_dentry_set+0x81e/0xa90 fs/exfat/dir.c:816
> exfat_get_dentry_set+0x36/0x210 fs/exfat/dir.c:859
> exfat_get_uniname_from_ext_entry fs/exfat/dir.c:39 [inline]
> exfat_readdir+0x950/0x1520 fs/exfat/dir.c:155
> exfat_iterate+0x3c7/0xad0 fs/exfat/dir.c:261
> wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
> iterate_dir+0x53e/0xb60 fs/readdir.c:110
> __do_sys_getdents64 fs/readdir.c:409 [inline]
> __se_sys_getdents64 fs/readdir.c:394 [inline]
> __ia32_sys_getdents64+0x14f/0x2e0 fs/readdir.c:394
> 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:
>
> Possible unsafe locking scenario:
>
> CPU0 CPU1
> ---- ----
> lock(&sbi->s_lock#2);
> lock(fs_reclaim);
> lock(&sbi->s_lock#2);
> lock(fs_reclaim);
>
> *** DEADLOCK ***
>
> 3 locks held by syz-executor.2/6265:
> #0: ffff88801db114c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191
> #1: ffff8880483da9e8 (&sb->s_type->i_mutex_key#24){++++}-{3:3}, at: wrap_directory_iterator+0x5a/0xe0 fs/readdir.c:56
> #2: ffff88804af1a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x33f/0xad0 fs/exfat/dir.c:256
>
> stack backtrace:
> CPU: 0 PID: 6265 Comm: syz-executor.2 Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #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: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]
> kmalloc_array_noprof include/linux/slab.h:699 [inline]
> __exfat_get_dentry_set+0x81e/0xa90 fs/exfat/dir.c:816
> exfat_get_dentry_set+0x36/0x210 fs/exfat/dir.c:859
> exfat_get_uniname_from_ext_entry fs/exfat/dir.c:39 [inline]
> exfat_readdir+0x950/0x1520 fs/exfat/dir.c:155
> exfat_iterate+0x3c7/0xad0 fs/exfat/dir.c:261
> wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
> iterate_dir+0x53e/0xb60 fs/readdir.c:110
> __do_sys_getdents64 fs/readdir.c:409 [inline]
> __se_sys_getdents64 fs/readdir.c:394 [inline]
> __ia32_sys_getdents64+0x14f/0x2e0 fs/readdir.c:394
> 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: 0023:0xf72f8579
> 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:00000000f5ec95ac EFLAGS: 00000292 ORIG_RAX: 00000000000000dc
> RAX: ffffffffffffffda RBX: 000000000000000a RCX: 0000000020002ec0
> RDX: 0000000000001000 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
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want to overwrite report's subsystems, reply with:
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> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [exfat?] possible deadlock in exfat_iterate (2)
2024-06-27 23:13 ` Namjae Jeon
@ 2024-06-27 23:13 ` syzbot
0 siblings, 0 replies; 3+ messages in thread
From: syzbot @ 2024-06-27 23:13 UTC (permalink / raw)
To: linkinjeon
Cc: linkinjeon, linux-fsdevel, linux-kernel, sj1557.seo,
syzkaller-bugs
> #syz test git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat.git dev
This crash does not have a reproducer. I cannot test it.
>
> 2024년 6월 27일 (목) 오후 9:58, syzbot
> <syzbot+df3558df41609451e4ac@syzkaller.appspotmail.com>님이 작성:
>>
>> Hello,
>>
>> syzbot found the following issue on:
>>
>> HEAD commit: 55027e689933 Merge tag 'input-for-v6.10-rc5' of git://git...
>> git tree: upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=16390ac1980000
>> kernel config: https://syzkaller.appspot.com/x/.config?x=53ab35b556129242
>> dashboard link: https://syzkaller.appspot.com/bug?extid=df3558df41609451e4ac
>> 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-55027e68.raw.xz
>> vmlinux: https://storage.googleapis.com/syzbot-assets/a36929b5a065/vmlinux-55027e68.xz
>> kernel image: https://storage.googleapis.com/syzbot-assets/d72de6f61ddc/bzImage-55027e68.xz
>>
>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>> Reported-by: syzbot+df3558df41609451e4ac@syzkaller.appspotmail.com
>>
>> ======================================================
>> WARNING: possible circular locking dependency detected
>> 6.10.0-rc5-syzkaller-00018-g55027e689933 #0 Not tainted
>> ------------------------------------------------------
>> syz-executor.2/6265 is trying to acquire lock:
>> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
>> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
>> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
>> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: __do_kmalloc_node mm/slub.c:4121 [inline]
>> ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_noprof+0xb5/0x420 mm/slub.c:4135
>>
>> but task is already holding lock:
>> ffff88804af1a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x33f/0xad0 fs/exfat/dir.c:256
>>
>> which lock already depends on the new lock.
>>
>>
>> the existing dependency chain (in reverse order) is:
>>
>> -> #1 (&sbi->s_lock#2){+.+.}-{3:3}:
>> __mutex_lock_common kernel/locking/mutex.c:608 [inline]
>> __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
>> exfat_evict_inode+0x25b/0x340 fs/exfat/inode.c:725
>> 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
>>
>> -> #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: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]
>> kmalloc_array_noprof include/linux/slab.h:699 [inline]
>> __exfat_get_dentry_set+0x81e/0xa90 fs/exfat/dir.c:816
>> exfat_get_dentry_set+0x36/0x210 fs/exfat/dir.c:859
>> exfat_get_uniname_from_ext_entry fs/exfat/dir.c:39 [inline]
>> exfat_readdir+0x950/0x1520 fs/exfat/dir.c:155
>> exfat_iterate+0x3c7/0xad0 fs/exfat/dir.c:261
>> wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
>> iterate_dir+0x53e/0xb60 fs/readdir.c:110
>> __do_sys_getdents64 fs/readdir.c:409 [inline]
>> __se_sys_getdents64 fs/readdir.c:394 [inline]
>> __ia32_sys_getdents64+0x14f/0x2e0 fs/readdir.c:394
>> 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:
>>
>> Possible unsafe locking scenario:
>>
>> CPU0 CPU1
>> ---- ----
>> lock(&sbi->s_lock#2);
>> lock(fs_reclaim);
>> lock(&sbi->s_lock#2);
>> lock(fs_reclaim);
>>
>> *** DEADLOCK ***
>>
>> 3 locks held by syz-executor.2/6265:
>> #0: ffff88801db114c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191
>> #1: ffff8880483da9e8 (&sb->s_type->i_mutex_key#24){++++}-{3:3}, at: wrap_directory_iterator+0x5a/0xe0 fs/readdir.c:56
>> #2: ffff88804af1a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x33f/0xad0 fs/exfat/dir.c:256
>>
>> stack backtrace:
>> CPU: 0 PID: 6265 Comm: syz-executor.2 Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #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: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]
>> kmalloc_array_noprof include/linux/slab.h:699 [inline]
>> __exfat_get_dentry_set+0x81e/0xa90 fs/exfat/dir.c:816
>> exfat_get_dentry_set+0x36/0x210 fs/exfat/dir.c:859
>> exfat_get_uniname_from_ext_entry fs/exfat/dir.c:39 [inline]
>> exfat_readdir+0x950/0x1520 fs/exfat/dir.c:155
>> exfat_iterate+0x3c7/0xad0 fs/exfat/dir.c:261
>> wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
>> iterate_dir+0x53e/0xb60 fs/readdir.c:110
>> __do_sys_getdents64 fs/readdir.c:409 [inline]
>> __se_sys_getdents64 fs/readdir.c:394 [inline]
>> __ia32_sys_getdents64+0x14f/0x2e0 fs/readdir.c:394
>> 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: 0023:0xf72f8579
>> 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:00000000f5ec95ac EFLAGS: 00000292 ORIG_RAX: 00000000000000dc
>> RAX: ffffffffffffffda RBX: 000000000000000a RCX: 0000000020002ec0
>> RDX: 0000000000001000 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
>>
>>
>> ---
>> This report is generated by a bot. It may contain errors.
>> See https://goo.gl/tpsmEJ for more information about syzbot.
>> syzbot engineers can be reached at syzkaller@googlegroups.com.
>>
>> syzbot will keep track of this issue. See:
>> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>>
>> If the report is already addressed, let syzbot know by replying with:
>> #syz fix: exact-commit-title
>>
>> If you want to overwrite report's subsystems, reply with:
>> #syz set subsystems: new-subsystem
>> (See the list of subsystem names on the web dashboard)
>>
>> If the report is a duplicate of another one, reply with:
>> #syz dup: exact-subject-of-another-report
>>
>> If you want to undo deduplication, reply with:
>> #syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-06-27 23:13 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2024-06-27 12:58 [syzbot] [exfat?] possible deadlock in exfat_iterate (2) syzbot
2024-06-27 23:13 ` Namjae Jeon
2024-06-27 23:13 ` syzbot
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