Extracting prog: 4m52.270897298s Minimizing prog: 55m32.380995419s Simplifying prog options: 14m19.02147033s Extracting C: 5m10.888509448s Simplifying C: 0s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program crashed: INFO: task hung in blkdev_get_by_dev single: successfully extracted reproducer found reproducer with 6 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)) ioctl$NBD_DO_IT(r1, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) ioctl$NBD_SET_SOCK(r1, 0xab00, 0xffffffffffffffff) ioctl$NBD_DO_IT(r1, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(0xffffffffffffffff, 0xab00, r1) ioctl$NBD_DO_IT(0xffffffffffffffff, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) r0 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r0, 0xab00, r1) ioctl$NBD_DO_IT(r0, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: ioctl$NBD_SET_SIZE_BLOCKS(0xffffffffffffffff, 0xab07, 0xb) r0 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r0, 0xab00, r1) ioctl$NBD_DO_IT(r0, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(0x0, 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(0x0, 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, 0x0) ioctl$NBD_SET_SOCK(r1, 0xab00, 0xffffffffffffffff) ioctl$NBD_DO_IT(r1, 0xab03) program did not crash extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT program crashed: no output from test machine a never seen crash title: no output from test machine, ignore simplifying guilty program options testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program crashed: INFO: task hung in blkdev_get_by_dev extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT program crashed: no output from test machine a never seen crash title: no output from test machine, ignore testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program crashed: INFO: task hung in blkdev_get_by_dev validation run: crashed=true testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program crashed: INFO: task hung in blkdev_get_by_dev validation run: crashed=true testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$ndb-ioctl$NBD_SET_SIZE_BLOCKS-syz_open_dev$ndb-socketpair$nbd-ioctl$NBD_SET_SOCK-ioctl$NBD_DO_IT detailed listing: executing program 0: r0 = syz_open_dev$ndb(&(0x7f0000000000), 0x0, 0x0) ioctl$NBD_SET_SIZE_BLOCKS(r0, 0xab07, 0xb) r1 = syz_open_dev$ndb(&(0x7f00000001c0), 0x0, 0x103001) socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000080)={0xffffffffffffffff}) ioctl$NBD_SET_SOCK(r1, 0xab00, r2) ioctl$NBD_DO_IT(r1, 0xab03) program crashed: INFO: task hung in blkdev_get_by_dev validation run: crashed=true reproducing took 1h29m37.331521225s repro crashed as (corrupted=false): INFO: task udevd:3937 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:0 pid:3937 ppid:1 flags:0x00000004 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562 schedule+0xc4/0x170 kernel/sched/core.c:6638 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 blkdev_get_by_dev+0x118/0x8b8 block/bdev.c:832 blkdev_open+0x108/0x2a0 block/fops.c:500 do_dentry_open+0x738/0xf8c fs/open.c:882 vfs_open+0x7c/0x90 fs/open.c:1015 do_open fs/namei.c:3634 [inline] path_openat+0x1fc0/0x27a0 fs/namei.c:3791 do_filp_open+0x198/0x38c fs/namei.c:3818 do_sys_openat2+0x134/0x3fc fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x11c/0x150 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 INFO: task syz.0.17:4540 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:0 pid:4540 ppid:4453 flags:0x00000001 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562 schedule+0xc4/0x170 kernel/sched/core.c:6638 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 blkdev_put+0xe8/0x6b0 block/bdev.c:930 blkdev_close+0x54/0x94 block/fops.c:514 __fput+0x1b4/0x7b0 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x1f4/0x280 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x20f8/0x2c84 arch/arm64/kernel/signal.c:1151 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 INFO: task syz.0.17:4541 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:0 pid:4541 ppid:4453 flags:0x00000009 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562 schedule+0xc4/0x170 kernel/sched/core.c:6638 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 blkdev_put+0xe8/0x6b0 block/bdev.c:930 blkdev_close+0x54/0x94 block/fops.c:514 __fput+0x1b4/0x7b0 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x1f4/0x280 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x20f8/0x2c84 arch/arm64/kernel/signal.c:1151 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffff800015507db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffff8000155085d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffff800015507440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349 1 lock held by udevd/3937: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x118/0x8b8 block/bdev.c:832 2 locks held by getty/4079: #0: ffff0000d6a9d098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80001f9962f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2e8/0xfa8 drivers/tty/n_tty.c:2198 2 locks held by kworker/u5:1/4402: #0: ffff0000ce95a138 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1 #1: ffff800020bd7c40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267 1 lock held by udevd/4539: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x118/0x8b8 block/bdev.c:832 1 lock held by syz.0.17/4540: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe8/0x6b0 block/bdev.c:930 1 lock held by syz.0.17/4541: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe8/0x6b0 block/bdev.c:930 ============================================= final repro crashed as (corrupted=false): INFO: task udevd:3937 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:0 pid:3937 ppid:1 flags:0x00000004 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562 schedule+0xc4/0x170 kernel/sched/core.c:6638 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 blkdev_get_by_dev+0x118/0x8b8 block/bdev.c:832 blkdev_open+0x108/0x2a0 block/fops.c:500 do_dentry_open+0x738/0xf8c fs/open.c:882 vfs_open+0x7c/0x90 fs/open.c:1015 do_open fs/namei.c:3634 [inline] path_openat+0x1fc0/0x27a0 fs/namei.c:3791 do_filp_open+0x198/0x38c fs/namei.c:3818 do_sys_openat2+0x134/0x3fc fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x11c/0x150 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 INFO: task syz.0.17:4540 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:0 pid:4540 ppid:4453 flags:0x00000001 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562 schedule+0xc4/0x170 kernel/sched/core.c:6638 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 blkdev_put+0xe8/0x6b0 block/bdev.c:930 blkdev_close+0x54/0x94 block/fops.c:514 __fput+0x1b4/0x7b0 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x1f4/0x280 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x20f8/0x2c84 arch/arm64/kernel/signal.c:1151 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 INFO: task syz.0.17:4541 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:0 pid:4541 ppid:4453 flags:0x00000009 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562 schedule+0xc4/0x170 kernel/sched/core.c:6638 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 blkdev_put+0xe8/0x6b0 block/bdev.c:930 blkdev_close+0x54/0x94 block/fops.c:514 __fput+0x1b4/0x7b0 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x1f4/0x280 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x20f8/0x2c84 arch/arm64/kernel/signal.c:1151 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffff800015507db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffff8000155085d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffff800015507440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349 1 lock held by udevd/3937: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x118/0x8b8 block/bdev.c:832 2 locks held by getty/4079: #0: ffff0000d6a9d098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80001f9962f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2e8/0xfa8 drivers/tty/n_tty.c:2198 2 locks held by kworker/u5:1/4402: #0: ffff0000ce95a138 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1 #1: ffff800020bd7c40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267 1 lock held by udevd/4539: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x118/0x8b8 block/bdev.c:832 1 lock held by syz.0.17/4540: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe8/0x6b0 block/bdev.c:930 1 lock held by syz.0.17/4541: #0: ffff0000ce8fa4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe8/0x6b0 block/bdev.c:930 =============================================