[syzbot] [hfs?] INFO: task hung in hfs_find_init

From: syzbot
Date: Thu Aug 31 2023 - 15:46:14 EST


Hello,

syzbot found the following issue on:

HEAD commit: 626932085009 Add linux-next specific files for 20230825
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=129f740ba80000
kernel config: https://syzkaller.appspot.com/x/.config?x=8a8c992a790e5073
dashboard link: https://syzkaller.appspot.com/bug?extid=dd327730db1381d8d2a2
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15cbe42fa80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17eab870680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/46ec18b3c2fb/disk-62693208.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b4ea0cb78498/vmlinux-62693208.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5fb3938c7272/bzImage-62693208.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/f4d93eaec6e2/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dd327730db1381d8d2a2@xxxxxxxxxxxxxxxxxxxxxxxxx

INFO: task kworker/u4:13:2908 blocked for more than 143 seconds.
Not tainted 6.5.0-rc7-next-20230825-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:13 state:D stack:25664 pid:2908 ppid:2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0xee1/0x59f0 kernel/sched/core.c:6695
schedule+0xe7/0x1b0 kernel/sched/core.c:6771
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6830
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
hfs_find_init+0x17f/0x220 fs/hfs/bfind.c:33
hfs_ext_write_extent+0x18e/0x1f0 fs/hfs/extent.c:141
hfs_write_inode+0xc4/0x9f0 fs/hfs/inode.c:431
write_inode fs/fs-writeback.c:1456 [inline]
__writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
__writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
wb_check_background_flush fs/fs-writeback.c:2142 [inline]
wb_do_writeback fs/fs-writeback.c:2230 [inline]
wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
process_one_work+0x887/0x15d0 kernel/workqueue.c:2630
process_scheduled_works kernel/workqueue.c:2703 [inline]
worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784
kthread+0x33a/0x430 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
</TASK>
INFO: task syz-executor624:5050 blocked for more than 143 seconds.
Not tainted 6.5.0-rc7-next-20230825-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor624 state:D stack:26944 pid:5050 ppid:5049 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0xee1/0x59f0 kernel/sched/core.c:6695
schedule+0xe7/0x1b0 kernel/sched/core.c:6771
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6830
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
hfs_find_init+0x17f/0x220 fs/hfs/bfind.c:33
hfs_ext_read_extent+0x19c/0x9d0 fs/hfs/extent.c:200
hfs_extend_file+0x4e0/0xb10 fs/hfs/extent.c:401
hfs_bmap_reserve+0x29c/0x370 fs/hfs/btree.c:234
__hfs_ext_write_extent+0x3cb/0x520 fs/hfs/extent.c:121
__hfs_ext_cache_extent fs/hfs/extent.c:174 [inline]
hfs_ext_read_extent+0x805/0x9d0 fs/hfs/extent.c:202
hfs_extend_file+0x4e0/0xb10 fs/hfs/extent.c:401
hfs_get_block+0x17f/0x820 fs/hfs/extent.c:353
__block_write_begin_int+0x3c0/0x1470 fs/buffer.c:2107
__block_write_begin fs/buffer.c:2157 [inline]
block_write_begin+0xb1/0x490 fs/buffer.c:2216
cont_write_begin+0x52f/0x730 fs/buffer.c:2573
hfs_write_begin+0x87/0x140 fs/hfs/inode.c:58
generic_perform_write+0x278/0x600 mm/filemap.c:3945
__generic_file_write_iter+0x1f9/0x240 mm/filemap.c:4040
generic_file_write_iter+0xe3/0x350 mm/filemap.c:4066
call_write_iter include/linux/fs.h:1985 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x650/0xe40 fs/read_write.c:584
ksys_write+0x12f/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f7094b1ea59
RSP: 002b:00007ffe889a4368 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7094b1ea59
RDX: 000000000208e24b RSI: 0000000020000180 RDI: 0000000000000004
RBP: 00007f7094b925f0 R08: 00005555570c84c0 R09: 00005555570c84c0
R10: 00000000000002ba R11: 0000000000000246 R12: 00007ffe889a4390
R13: 00007ffe889a45b8 R14: 431bde82d7b634db R15: 00007f7094b6703b
</TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.5.0-rc7-next-20230825-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xfac/0x1230 kernel/hung_task.c:379
kthread+0x33a/0x430 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4486 Comm: klogd Not tainted 6.5.0-rc7-next-20230825-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x20 kernel/kcov.c:290
Code: 00 00 f3 0f 1e fa 48 8b 0c 24 48 89 f2 48 89 fe bf 06 00 00 00 e9 f8 fe ff ff 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 8b 0c 24 <40> 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 d6 fe ff ff 66 0f 1f 44
RSP: 0018:ffffc9000316f4a0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc9000316f528 RCX: ffffffff813a6214
RDX: ffff88807d690000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc9000316fca8
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000001
FS: 00007faa97852380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056143bacf680 CR3: 000000007d4dd000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
unwind_next_frame+0x1aa4/0x2390 arch/x86/kernel/unwind_orc.c:648
arch_stack_walk+0xfa/0x170 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
__kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:762 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
kmem_cache_alloc_node+0x185/0x3f0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:634
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6299
sock_alloc_send_pskb+0x7c8/0x950 net/core/sock.c:2794
unix_dgram_sendmsg+0x455/0x1c30 net/unix/af_unix.c:1953
sock_sendmsg_nosec net/socket.c:730 [inline]
sock_sendmsg+0xd9/0x180 net/socket.c:753
__sys_sendto+0x255/0x340 net/socket.c:2176
__do_sys_sendto net/socket.c:2188 [inline]
__se_sys_sendto net/socket.c:2184 [inline]
__x64_sys_sendto+0xe0/0x1b0 net/socket.c:2184
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7faa979b49b5
Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fffe91a6858 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007faa979b49b5
RDX: 000000000000008b RSI: 000055f315610e90 RDI: 0000000000000003
RBP: 000055f31560c910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013
R13: 00007faa97b42212 R14: 00007fffe91a6958 R15: 0000000000000000
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.859 msecs


---
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