bisecting fixing commit since 4707d8e5727387e36ea99c74d5ff0ad227700fd0 building syzkaller on e6b89e4e5adde15c0dc0a241e03dc215f2e249b3 testing commit 4707d8e5727387e36ea99c74d5ff0ad227700fd0 with gcc (GCC) 8.1.0 kernel signature: 7e7b6792e4e3dff268aac921fe00d77166766e86df25477a5583b457e3eb1028 run #0: crashed: INFO: task hung in pipe_read run #1: crashed: INFO: task hung in vfs_unlink run #2: crashed: INFO: task hung in pipe_write run #3: crashed: INFO: task hung in pipe_write run #4: crashed: INFO: task hung in pipe_read run #5: crashed: INFO: task hung in pipe_write run #6: crashed: INFO: task hung in pipe_write run #7: crashed: INFO: task hung in pipe_read run #8: crashed: INFO: task hung in pipe_write run #9: crashed: INFO: task hung in pipe_write testing current HEAD b09c34517e1ac4018e3bb75ed5c8610a8a1f486b testing commit b09c34517e1ac4018e3bb75ed5c8610a8a1f486b with gcc (GCC) 8.1.0 kernel signature: 9aeb395a7543730f1a4ef0aa33abbe06087bfe1b930bcbf79b594095f412ca2e run #0: crashed: INFO: task hung in pipe_write run #1: crashed: INFO: task hung in pipe_read run #2: crashed: INFO: task hung in pipe_write run #3: crashed: INFO: task hung in pipe_write run #4: crashed: INFO: task hung in pipe_read run #5: crashed: INFO: task hung in pipe_write run #6: crashed: INFO: task hung in pipe_write run #7: crashed: INFO: task hung in pipe_write run #8: crashed: INFO: task hung in pipe_write run #9: crashed: INFO: task hung in pipe_write revisions tested: 2, total time: 31m53.582543199s (build: 18m14.703785126s, test: 12m47.348327567s) the crash still happens on HEAD commit msg: Linux 4.19.149 crash: INFO: task hung in pipe_write batman_adv: batadv0: Interface activated: batadv_slave_1 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready INFO: task syz-executor.2:15871 blocked for more than 140 seconds. Not tainted 4.19.149-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29448 15871 6587 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __pipe_lock fs/pipe.c:83 [inline] pipe_write+0xa6/0xd00 fs/pipe.c:380 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cae9 Code: Bad RIP value. RSP: 002b:00007f18df400c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050ca00 RCX: 000000000045cae9 RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf454 R15: 00007f18df4016d4 INFO: task syz-executor.2:16030 blocked for more than 140 seconds. Not tainted 4.19.149-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29448 16030 6587 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __pipe_lock fs/pipe.c:83 [inline] pipe_write+0xa6/0xd00 fs/pipe.c:380 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cae9 Code: Bad RIP value. RSP: 002b:00007f18df400c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050ca00 RCX: 000000000045cae9 RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf454 R15: 00007f18df4016d4 INFO: task syz-executor.4:17189 blocked for more than 140 seconds. Not tainted 4.19.149-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29784 17189 6588 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __pipe_lock fs/pipe.c:83 [inline] pipe_write+0xa6/0xd00 fs/pipe.c:380 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cae9 Code: Bad RIP value. RSP: 002b:00007f7648bdbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050ca00 RCX: 000000000045cae9 RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf454 R15: 00007f7648bdc6d4 INFO: task syz-executor.2:17392 blocked for more than 140 seconds. Not tainted 4.19.149-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29448 17392 6587 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __pipe_lock fs/pipe.c:83 [inline] pipe_write+0xa6/0xd00 fs/pipe.c:380 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cae9 Code: Bad RIP value. RSP: 002b:00007f18df400c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050ca00 RCX: 000000000045cae9 RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf454 R15: 00007f18df4016d4 INFO: task syz-executor.4:17780 blocked for more than 140 seconds. Not tainted 4.19.149-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29784 17780 6588 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __pipe_lock fs/pipe.c:83 [inline] pipe_write+0xa6/0xd00 fs/pipe.c:380 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cae9 Code: Bad RIP value. RSP: 002b:00007f7648bdbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050ca00 RCX: 000000000045cae9 RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cec R14: 00000000004cf454 R15: 00007f7648bdc6d4 Showing all locks held in the system: 1 lock held by khungtaskd/1068: #0: 000000001c8378ed (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4442 1 lock held by syz-execprog/6579: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_read+0xaa/0x7b0 fs/pipe.c:274 1 lock held by syz-execprog/6580: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_wait+0x185/0x1b0 fs/pipe.c:118 2 locks held by kworker/u4:5/7779: 1 lock held by syz-executor.2/15586: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_wait+0x185/0x1b0 fs/pipe.c:118 1 lock held by syz-executor.2/15871: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/16030: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/16945: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_wait+0x185/0x1b0 fs/pipe.c:118 1 lock held by syz-executor.4/17189: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/17392: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/17780: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/17888: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/17917: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/18517: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/18727: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/18882: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/18904: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/19090: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/19210: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/19254: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_wait+0x185/0x1b0 fs/pipe.c:118 1 lock held by syz-executor.1/19272: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_wait+0x185/0x1b0 fs/pipe.c:118 1 lock held by syz-executor.4/19284: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/19321: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/19389: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/19425: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/19795: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/20148: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/20270: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/20611: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/20650: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/20830: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/20907: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/20933: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/20961: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/21152: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/21364: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/21530: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/21570: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/21652: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/21777: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/21909: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/21919: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/21990: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/22015: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22043: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/22085: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_wait+0x185/0x1b0 fs/pipe.c:118 1 lock held by syz-executor.4/22102: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22108: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22154: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/22192: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22364: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/22430: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22533: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22681: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/22849: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/22853: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23099: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23100: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23101: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23118: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23133: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23136: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23156: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23181: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23277: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23283: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23290: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23297: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23303: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23312: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23343: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23351: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23356: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.1/23379: #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 000000001065c9e9 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23387: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23407: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23444: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23448: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23452: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23470: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23471: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23492: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23494: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23504: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.0/23540: #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000df549075 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23542: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.4/23592: #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000a616eff7 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23608: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23641: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 1 lock held by syz-executor.2/23657: #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83 [inline] #0: 00000000c681e384 (&pipe->mutex/1){+.+.}, at: pipe_write+0xa6/0xd00 fs/pipe.c:380 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1068 Comm: khungtaskd Not tainted 4.19.149-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x17c/0x22a lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf5/0x119 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3674 Comm: systemd-journal Not tainted 4.19.149-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:find_held_lock+0x221/0x300 kernel/locking/lockdep.c:3541 Code: 42 80 3c 30 00 0f 85 b7 00 00 00 4c 3b 7b 10 74 0b 49 89 dc e9 31 ff ff ff 48 89 c3 48 b8 00 00 00 00 00 fc ff df 48 8b 75 d0 <48> 89 f2 48 c1 ea 03 0f b6 14 02 48 89 f0 83 e0 07 83 c0 03 38 d0 RSP: 0018:ffff888094ea7cf8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff888094e9ec48 RCX: ffff888094ea7d78 RDX: 1ffff110129d3d8b RSI: ffff888094ea7d78 RDI: ffff888094e9ec58 RBP: ffff888094ea7d30 R08: 0000000000000000 R09: ffffed1015d4473a R10: ffffed1015d4473a R11: ffff8880aea239d3 R12: ffffffff8858c620 R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8858c620 FS: 00007fce4f9c18c0(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fce4cdd8000 CR3: 0000000094ee8000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_release kernel/locking/lockdep.c:3676 [inline] lock_release+0x257/0x840 kernel/locking/lockdep.c:3926 rcu_lock_release include/linux/rcupdate.h:247 [inline] rcu_read_unlock include/linux/rcupdate.h:681 [inline] dput+0x126/0x460 fs/dcache.c:834 path_put+0x2c/0x60 fs/namei.c:484 do_faccessat+0x38e/0x630 fs/open.c:431 __do_sys_access fs/open.c:449 [inline] __se_sys_access fs/open.c:447 [inline] __x64_sys_access+0x54/0x80 fs/open.c:447 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fce4ec7d9c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffd531f1718 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffd531f4630 RCX: 00007fce4ec7d9c7 RDX: 00007fce4f6eea00 RSI: 0000000000000000 RDI: 000055c13615b9a3 RBP: 00007ffd531f1750 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffd531f4630 R15: 00007ffd531f1c40