Hello,
syzbot found the following crash on:
HEAD commit: b11964ad ANDROID: cuttlefish: enable CONFIG_INET_UDP_DIAG=y
git tree: android-4.14
console output:
https://syzkaller.appspot.com/x/log.txt?x=14d39723200000
kernel config:
https://syzkaller.appspot.com/x/.config?x=322dd7397c84f390
dashboard link:
https://syzkaller.appspot.com/bug?extid=94194c9c1942daee32f4
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:
https://syzkaller.appspot.com/x/repro.syz?x=120c6dad200000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+94194c...@syzkaller.appspotmail.com
random: cc1: uninitialized urandom read (8 bytes read)
audit: type=1400 audit(1552161453.819:9): avc: denied { map } for
pid=1946 comm="syz-execprog" path="/root/syzkaller-shm673589165" dev="sda1"
ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1
INFO: task syz-executor.2:1962 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2 D25144 1962 1 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405
__blkdev_driver_ioctl block/ioctl.c:297 [inline]
blkdev_ioctl+0x4d9/0x1810 block/ioctl.c:594
block_ioctl+0xd9/0x120 fs/block_dev.c:1881
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task syz-executor.4:1970 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4 D25640 1970 1 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
lo_open+0x19/0xb0 drivers/block/loop.c:1624
__blkdev_get+0x267/0xf90 fs/block_dev.c:1472
blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
do_dentry_open+0x41b/0xd60 fs/open.c:764
vfs_open+0x105/0x230 fs/open.c:878
do_last fs/namei.c:3455 [inline]
path_openat+0xb6b/0x2b70 fs/namei.c:3597
do_filp_open+0x1a1/0x280 fs/namei.c:3631
do_sys_open+0x2ca/0x590 fs/open.c:1071
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task syz-executor.5:1972 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5 D25640 1972 1 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
lo_open+0x19/0xb0 drivers/block/loop.c:1624
__blkdev_get+0x267/0xf90 fs/block_dev.c:1472
blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
do_dentry_open+0x41b/0xd60 fs/open.c:764
vfs_open+0x105/0x230 fs/open.c:878
do_last fs/namei.c:3455 [inline]
path_openat+0xb6b/0x2b70 fs/namei.c:3597
do_filp_open+0x1a1/0x280 fs/namei.c:3631
do_sys_open+0x2ca/0x590 fs/open.c:1071
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task syz-executor.0:1975 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0 D25640 1975 1 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
lo_open+0x19/0xb0 drivers/block/loop.c:1624
__blkdev_get+0x963/0xf90 fs/block_dev.c:1537
blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
do_dentry_open+0x41b/0xd60 fs/open.c:764
vfs_open+0x105/0x230 fs/open.c:878
do_last fs/namei.c:3455 [inline]
path_openat+0xb6b/0x2b70 fs/namei.c:3597
do_filp_open+0x1a1/0x280 fs/namei.c:3631
do_sys_open+0x2ca/0x590 fs/open.c:1071
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task syz-executor.1:1978 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1 D25560 1978 1 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
lo_open+0x19/0xb0 drivers/block/loop.c:1624
__blkdev_get+0x267/0xf90 fs/block_dev.c:1472
blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
do_dentry_open+0x41b/0xd60 fs/open.c:764
vfs_open+0x105/0x230 fs/open.c:878
do_last fs/namei.c:3455 [inline]
path_openat+0xb6b/0x2b70 fs/namei.c:3597
do_filp_open+0x1a1/0x280 fs/namei.c:3631
do_sys_open+0x2ca/0x590 fs/open.c:1071
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task syz-executor.3:3042 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3 D28688 3042 1968 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
blkdev_reread_part+0x1b/0x40 block/ioctl.c:192
loop_reread_partitions+0x72/0x80 drivers/block/loop.c:615
loop_set_status+0xbff/0x11f0 drivers/block/loop.c:1184
INFO: task blkid:3043 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid D28664 3043 2920 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
__lo_release drivers/block/loop.c:1644 [inline]
lo_release+0x78/0x190 drivers/block/loop.c:1668
__blkdev_put+0x518/0x6d0 fs/block_dev.c:1791
blkdev_close+0x86/0xb0 fs/block_dev.c:1863
__fput+0x25e/0x700 fs/file_table.c:210
task_work_run+0x118/0x190 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x13b/0x160 arch/x86/entry/common.c:163
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:267 [inline]
do_syscall_64+0x372/0x4b0 arch/x86/entry/common.c:294
INFO: task blkid:3045 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid D29344 3045 308 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405
__blkdev_driver_ioctl block/ioctl.c:297 [inline]
blkdev_ioctl+0x4d9/0x1810 block/ioctl.c:594
block_ioctl+0xd9/0x120 fs/block_dev.c:1881
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task blkid:3048 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid D27232 3048 2926 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
do_dentry_open+0x41b/0xd60 fs/open.c:764
vfs_open+0x105/0x230 fs/open.c:878
do_last fs/namei.c:3455 [inline]
path_openat+0xb6b/0x2b70 fs/namei.c:3597
do_filp_open+0x1a1/0x280 fs/namei.c:3631
do_sys_open+0x2ca/0x590 fs/open.c:1071
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task blkid:3052 blocked for more than 140 seconds.
Not tainted 4.14.105+ #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid D29264 3052 2919 0x00000004
Call Trace:
schedule+0x92/0x1c0 kernel/sched/core.c:3492
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3550
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
do_dentry_open+0x41b/0xd60 fs/open.c:764
vfs_open+0x105/0x230 fs/open.c:878
do_last fs/namei.c:3455 [inline]
path_openat+0xb6b/0x2b70 fs/namei.c:3597
do_filp_open+0x1a1/0x280 fs/namei.c:3631
do_sys_open+0x2ca/0x590 fs/open.c:1071
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
Showing all locks held in the system:
1 lock held by khungtaskd/23:
#0: (tasklist_lock){.+.+}, at: [<ffffffffa3a00e0c>]
debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541
2 locks held by getty/1757:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffffa4538782>]
tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:275
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffffa4533ba7>]
n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.2/1962:
#0: (loop_ctl_mutex/1){+.+.}, at: [<ffffffffa45e87a3>]
lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405
2 locks held by syz-executor.4/1970:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
#1: (loop_index_mutex){+.+.}, at: [<ffffffffa45e3b99>] lo_open+0x19/0xb0
drivers/block/loop.c:1624
2 locks held by syz-executor.5/1972:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
#1: (loop_index_mutex){+.+.}, at: [<ffffffffa45e3b99>] lo_open+0x19/0xb0
drivers/block/loop.c:1624
2 locks held by syz-executor.0/1975:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
#1: (loop_index_mutex){+.+.}, at: [<ffffffffa45e3b99>] lo_open+0x19/0xb0
drivers/block/loop.c:1624
2 locks held by syz-executor.1/1978:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
#1: (loop_index_mutex){+.+.}, at: [<ffffffffa45e3b99>] lo_open+0x19/0xb0
drivers/block/loop.c:1624
2 locks held by syz-executor.3/3042:
#0: (loop_ctl_mutex/1){+.+.}, at: [<ffffffffa45e87a3>]
lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405
#1: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa431b5ab>]
blkdev_reread_part+0x1b/0x40 block/ioctl.c:192
3 locks held by blkid/3043:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e167d1>]
__blkdev_put+0xb1/0x6d0 fs/block_dev.c:1778
#1: (loop_index_mutex){+.+.}, at: [<ffffffffa45ea1d9>]
lo_release+0x19/0x190 drivers/block/loop.c:1667
#2: (loop_ctl_mutex#2){+.+.}, at: [<ffffffffa45ea238>] __lo_release
drivers/block/loop.c:1644 [inline]
#2: (loop_ctl_mutex#2){+.+.}, at: [<ffffffffa45ea238>]
lo_release+0x78/0x190 drivers/block/loop.c:1668
1 lock held by blkid/3045:
#0: (loop_ctl_mutex/1){+.+.}, at: [<ffffffffa45e87a3>]
lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405
1 lock held by blkid/3048:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
1 lock held by blkid/3052:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
1 lock held by blkid/3054:
#0: (&bdev->bd_mutex){+.+.}, at: [<ffffffffa3e16ee3>]
__blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.105+ #29
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xb9/0x10e lib/dump_stack.c:53
nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.105+ #29
task: ffffffffa5c31200 task.stack: ffffffffa5c00000
RIP: 0010:cpumask_next_and+0x12/0xa0 lib/cpumask.c:35
RSP: 0018:ffff8881dba078d0 EFLAGS: 00000246
RAX: ffffed103b740fa2 RBX: ffff8881dba07ad8 RCX: 1ffffffff4c06939
RDX: ffff8881dba1e4b8 RSI: ffff8881da96af28 RDI: 0000000000000000
RBP: 000000000002a200 R08: 0000000000000001 R09: ffff8881dba2a200
R10: ffffed103b740f64 R11: ffff8881dba07b27 R12: ffff8881dba2a200
R13: ffff8881da96af28 R14: ffff8881dba1e4b8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000781f04 CR3: 00000001bc626005 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
update_sg_lb_stats kernel/sched/fair.c:9497 [inline]
update_sd_lb_stats kernel/sched/fair.c:9746 [inline]
find_busiest_group+0x3b8/0x3950 kernel/sched/fair.c:10083
load_balance+0x3f9/0x2a00 kernel/sched/fair.c:10395
rebalance_domains+0x785/0xd50 kernel/sched/fair.c:11091
run_rebalance_domains+0x60f/0x8e0 kernel/sched/fair.c:11355
__do_softirq+0x234/0x9ca kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x114/0x150 kernel/softirq.c:409
reschedule_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:811
</IRQ>
RIP: 0010:native_safe_halt+0x2/0x10 arch/x86/include/asm/irqflags.h:58
RSP: 0018:ffffffffa5c07d48 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02
RAX: 0000000000000007 RBX: ffffffffa602a508 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa5c31a2c
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffffa5c31200 R15: dffffc0000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
default_idle+0x50/0x390 arch/x86/kernel/process.c:564
cpuidle_idle_call kernel/sched/idle.c:159 [inline]
do_idle+0x2e6/0x390 kernel/sched/idle.c:268
cpu_startup_entry+0xc6/0xd0 kernel/sched/idle.c:374
start_kernel+0x712/0x74a init/main.c:710
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240
Code: 48 63 d2 e8 81 75 37 ff 5b 5d c3 0f 1f 40 00 66 2e 0f 1f 84 00 00 00
00 00 41 57 41 89 ff 41 56 49 89 d6 41 55 49 89 f5 41 54 55 <48> c7 c5 c4
4a 03 a6 49 89 ec 53 83 e5 07 e8 eb 15 b1 fe 49 c1
---
This bug is generated by a bot. It may contain errors.
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