syzbot

INFO: task syz-executor378:5844 blocked for more than 143 seconds.
      Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor378 state:D stack:27984 pid:5844  tgid:5838  ppid:5837   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764
 __schedule_loop kernel/sched/core.c:6841 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6856
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913
 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
 __down_write_common kernel/locking/rwsem.c:1304 [inline]
 __down_write kernel/locking/rwsem.c:1313 [inline]
 down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
 inode_lock_nested include/linux/fs.h:900 [inline]
 lock_rename fs/namei.c:3217 [inline]
 do_renameat2+0x62c/0x13f0 fs/namei.c:5161
 __do_sys_rename fs/namei.c:5273 [inline]
 __se_sys_rename fs/namei.c:5271 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:5271
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f89cd60e549
RSP: 002b:00007f89cd5a4218 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f89cd695658 RCX: 00007f89cd60e549
RDX: 00007f89cd5e7cc6 RSI: 00000000200004c0 RDI: 0000000020000240
RBP: 00007f89cd695650 R08: 00007fffe46e3cc7 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f89cd662634
R13: 0030656c69662f2e R14: 00736e6f69746361 R15: 0031656c69662f2e
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
2 locks held by getty/5578:
 #0: ffff88814ddb00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002fd62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
7 locks held by syz-executor378/5840:
2 locks held by syz-executor378/5844:
 #0: ffff88805a354420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547
 #1: ffff88805ac8b580 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:900 [inline]
 #1: ffff88805ac8b580 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3217 [inline]
 #1: ffff88805ac8b580 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: do_renameat2+0x62c/0x13f0 fs/namei.c:5161

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0x1058/0x10a0 kernel/hung_task.c:399
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5840 Comm: syz-executor378 Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:unwind_next_frame+0x315/0x22d0 arch/x86/kernel/unwind_orc.c:505
Code: 64 48 01 d2 48 01 f2 0f 84 42 01 00 00 48 8d 5a 04 4c 8d 72 05 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 0f b6 04 28 <84> c0 0f 85 58 18 00 00 4c 89 f0 48 c1 e8 03 0f b6 04 28 84 c0 0f
RSP: 0018:ffffc900041567b0 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffffff90b1ed4c RCX: ffffffff90366724
RDX: ffffffff90b1ed48 RSI: ffffffff90b1ed48 RDI: ffffffff816bb3f0
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffc90004156970
R10: ffffc900041568d0 R11: ffffffff81ab1d60 R12: 0000000000000000
R13: ffffc90004156880 R14: ffffffff90b1ed4d R15: ffffffff8238215b
FS:  00007f89cd5c56c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559892ce6600 CR3: 000000007b002000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4294 [inline]
 __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4306
 kmalloc_noprof include/linux/slab.h:905 [inline]
 qtree_write_dquot+0xf9/0x5b0 fs/quota/quota_tree.c:444
 v2_write_dquot+0x17a/0x270 fs/quota/quota_v2.c:372
 dquot_commit+0x399/0x490 fs/quota/dquot.c:512
 ext4_write_dquot+0x212/0x370 fs/ext4/super.c:6903
 mark_dquot_dirty fs/quota/dquot.c:370 [inline]
 mark_all_dquot_dirty+0x101/0x450 fs/quota/dquot.c:410
 __dquot_free_space+0x977/0xec0 fs/quota/dquot.c:1928
 dquot_free_space_nodirty include/linux/quotaops.h:374 [inline]
 dquot_free_space include/linux/quotaops.h:379 [inline]
 dquot_free_block include/linux/quotaops.h:390 [inline]
 ext4_xattr_block_set+0x145a/0x3160 fs/ext4/xattr.c:2081
 ext4_xattr_set_handle+0xce0/0x1580 fs/ext4/xattr.c:2458
 ext4_initxattrs+0xa3/0x120 fs/ext4/xattr_security.c:44
 security_inode_init_security+0x29c/0x480 security/security.c:1852
 __ext4_new_inode+0x388f/0x4630 fs/ext4/ialloc.c:1324
 ext4_create+0x279/0x550 fs/ext4/namei.c:2841
 lookup_open fs/namei.c:3651 [inline]
 open_last_lookups fs/namei.c:3750 [inline]
 path_openat+0x193c/0x3590 fs/namei.c:3986
 do_filp_open+0x27f/0x4e0 fs/namei.c:4016
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1427
 do_sys_open fs/open.c:1442 [inline]
 __do_sys_openat fs/open.c:1458 [inline]
 __se_sys_openat fs/open.c:1453 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1453
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f89cd60e549
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 18 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f89cd5c5218 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f89cd695648 RCX: 00007f89cd60e549
RDX: 0000000000103042 RSI: 0000000020000100 RDI: 00000000ffffff9c
RBP: 00007f89cd695640 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f89cd662634
R13: 0030656c69662f2e R14: 00736e6f69746361 R15: 0031656c69662f2e
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.329 msecs