Hello,
syzbot found the following issue on:
HEAD commit: 420102835862 Linux 6.1.134
git tree: linux-6.1.y
console output:
https://syzkaller.appspot.com/x/log.txt?x=1647efe4580000
kernel config:
https://syzkaller.appspot.com/x/.config?x=5b8d7e66d7963efe
dashboard link:
https://syzkaller.appspot.com/bug?extid=86129b61506f3a4600ee
compiler: Debian clang version 15.0.6, Debian LLD 15.0.6
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image:
https://storage.googleapis.com/syzbot-assets/91a5e36a108f/disk-42010283.raw.xz
vmlinux:
https://storage.googleapis.com/syzbot-assets/ec90f2faa77e/vmlinux-42010283.xz
kernel image:
https://storage.googleapis.com/syzbot-assets/dce3af94d7be/bzImage-42010283.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by:
[email protected]
INFO: task syz.1.580:6743 blocked for more than 143 seconds.
Not tainted 6.1.134-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.580 state:D stack:26192 pid:6743 ppid:4250 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6561
schedule+0xbf/0x180 kernel/sched/core.c:6637
__wait_on_freeing_inode fs/inode.c:2286 [inline]
find_inode_fast+0x315/0x450 fs/inode.c:995
iget_locked+0xc7/0x830 fs/inode.c:1360
__ext4_iget+0x25d/0x3ee0 fs/ext4/inode.c:4831
ext4_xattr_inode_cache_find fs/ext4/xattr.c:1499 [inline]
ext4_xattr_inode_lookup_create+0x510/0x1ff0 fs/ext4/xattr.c:1538
ext4_xattr_ibody_set+0x210/0x720 fs/ext4/xattr.c:2215
ext4_xattr_set_handle+0xc72/0x1560 fs/ext4/xattr.c:2392
ext4_xattr_set+0x26e/0x3d0 fs/ext4/xattr.c:2506
__vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
__vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
vfs_setxattr+0x21d/0x420 fs/xattr.c:309
do_setxattr fs/xattr.c:594 [inline]
setxattr+0x250/0x2b0 fs/xattr.c:617
path_setxattr+0x1bc/0x2a0 fs/xattr.c:636
__do_sys_setxattr fs/xattr.c:652 [inline]
__se_sys_setxattr fs/xattr.c:648 [inline]
__x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7e7018e169
RSP: 002b:00007f7e70f17038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f7e703b6080 RCX: 00007f7e7018e169
RDX: 0000200000001400 RSI: 00002000000001c0 RDI: 0000200000000200
RBP: 00007f7e70210a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000835 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f7e703b6080 R15: 00007ffd9e1c77b8
</TASK>
INFO: task syz.1.580:6745 blocked for more than 143 seconds.
Not tainted 6.1.134-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.580 state:D stack:25808 pid:6745 ppid:4250 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6561
schedule+0xbf/0x180 kernel/sched/core.c:6637
mb_cache_entry_wait_unused+0x162/0x240 fs/mbcache.c:148
ext4_evict_ea_inode+0x146/0x2e0 fs/ext4/xattr.c:444
ext4_evict_inode+0x19d/0x1150 fs/ext4/inode.c:181
evict+0x529/0x930 fs/inode.c:705
ext4_xattr_set_entry+0x183a/0x1fa0 fs/ext4/xattr.c:1798
ext4_xattr_block_set+0x1a92/0x3820 fs/ext4/xattr.c:1910
ext4_xattr_set_handle+0x1043/0x1560 fs/ext4/xattr.c:2395
ext4_xattr_set+0x26e/0x3d0 fs/ext4/xattr.c:2506
__vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
__vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
vfs_setxattr+0x21d/0x420 fs/xattr.c:309
do_setxattr fs/xattr.c:594 [inline]
setxattr+0x250/0x2b0 fs/xattr.c:617
path_setxattr+0x1bc/0x2a0 fs/xattr.c:636
__do_sys_setxattr fs/xattr.c:652 [inline]
__se_sys_setxattr fs/xattr.c:648 [inline]
__x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7e7018e169
RSP: 002b:00007f7e6ffff038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f7e703b6160 RCX: 00007f7e7018e169
RDX: 0000200000000080 RSI: 0000200000000180 RDI: 00002000000000c0
RBP: 00007f7e70210a68 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000032 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f7e703b6160 R15: 00007ffd9e1c77b8
</TASK>
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d32e910 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d32f110 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
2 locks held by getty/4011:
#0: ffff88807e388098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4249:
2 locks held by syz-executor/4262:
#0: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#0: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962
#1: ffff8880b8e3a998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
2 locks held by syz-executor/4376:
1 lock held by syz-executor/4399:
#0: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#0: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962
5 locks held by kworker/u4:8/5422:
#0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc900034e7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffffffff8e544210 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xd20 net/core/net_namespace.c:594
#3: ffff88801f3472f8 (&devlink->lock_key#10){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x132/0x2f0 net/devlink/leftover.c:12500
#4: ffffffff8d333c40 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:4019
3 locks held by syz.1.580/6743:
#0: ffff8880207d6460 (sb_writers#4){++++}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
#1: ffff888070be8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff888070be8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_setxattr+0x1dd/0x420 fs/xattr.c:308
#2: ffff888070be80c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline]
#2: ffff888070be80c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x270/0x1560 fs/ext4/xattr.c:2319
3 locks held by syz.1.580/6745:
#0: ffff8880207d6460 (sb_writers#4){++++}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
#1: ffff888070bec030 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff888070bec030 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_setxattr+0x1dd/0x420 fs/xattr.c:308
#2: ffff888070bebcf8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline]
#2: ffff888070bebcf8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x270/0x1560 fs/ext4/xattr.c:2319
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf88/0xfd0 kernel/hung_task.c:377
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3612 Comm: klogd Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_switch+0x7c/0xe0 kernel/kcov.c:349
Code: c2 49 39 d2 74 71 4c 8b 74 d6 10 65 8b 05 e4 1d 78 7e 25 00 01 ff 00 74 11 3d 00 01 00 00 75 de 41 83 bb 1c 16 00 00 00 74 d4 <41> 8b 83 f8 15 00 00 83 f8 03 75 c8 49 8b 8b 00 16 00 00 45 8b bb
RSP: 0018:ffffc90003247658 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000075 RCX: 000000000000008b
RDX: 0000000000000002 RSI: ffffffff8e89e400 RDI: 0000000000000075
RBP: ffffc90003247770 R08: 0000000000000005 R09: ffffffff8aab2b35
R10: 000000000000000a R11: ffff88807c4f1dc0 R12: ffff0a1000000600
R13: ffff001000000600 R14: 0000000000000063 R15: 1ffffffff1619a59
FS: 00007f48d767b380(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa2435b6ca0 CR3: 000000007e5ff000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
format_decode+0xab5/0x1f10 lib/vsprintf.c:2615
vsnprintf+0x14d/0x1c70 lib/vsprintf.c:2757
sprintf+0xd6/0x120 lib/vsprintf.c:3009
print_time kernel/printk/printk.c:1274 [inline]
info_print_prefix+0x167/0x300 kernel/printk/printk.c:1300
record_print_text+0x142/0x430 kernel/printk/printk.c:1349
syslog_print+0x3d8/0x620 kernel/printk/printk.c:1560
do_syslog+0x819/0x910 kernel/printk/printk.c:1679
__do_sys_syslog kernel/printk/printk.c:1771 [inline]
__se_sys_syslog kernel/printk/printk.c:1769 [inline]
__x64_sys_syslog+0x78/0x90 kernel/printk/printk.c:1769
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f48d77dcfa7
Code: 73 01 c3 48 8b 0d 81 ce 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 51 ce 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007fffa19a7d68 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: ffffffffffffffda RBX: 00007f48d797b4a0 RCX: 00007f48d77dcfa7
RDX: 00000000000003ff RSI: 00007f48d797b4a0 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000005 R09: 30c3065a11fc9209
R10: 0000000000004000 R11: 0000000000000206 R12: 00007f48d797b4a0
R13: 00007f48d796b212 R14: 00007f48d797b51e R15: 00007f48d797b51e
</TASK>
---
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