------------[ cut here ]------------
WARNING: CPU: 1 PID: 18533 at mm/page_alloc.c:3556 __alloc_pages_slowpath mm/page_alloc.c:3556 [inline]
WARNING: CPU: 1 PID: 18533 at mm/page_alloc.c:3556 __alloc_pages_nodemask+0x13a0/0x1bd0 mm/page_alloc.c:3862
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 18533 Comm: syz-executor.0 Not tainted 4.9.141+ #23
 ffff8801b4fdef80 ffffffff81b42e79 ffffffff82a38ce0 00000000ffffffff
 ffffffff82a96600 0000000000000001 0000000000000009 ffff8801b4fdf040
 ffffffff813f7125[  451.703602] audit_printk_skb: 1466 callbacks suppressed
audit: type=1400 audit(1574005712.366:29180): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.376:29181): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.376:29182): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.386:29183): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.396:29184): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.406:29185): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.406:29186): avc:  denied  { net_admin } for  pid=2082 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1574005712.486:29187): avc:  denied  { dac_override } for  pid=18541 comm="syz-executor.5" capability=1  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1

======================================================
[ INFO: possible circular locking dependency detected ]
4.9.141+ #23 Not tainted
-------------------------------------------------------
syz-executor.5/18542 is trying to acquire lock:
 (&p->lock){+.+.+.}, at: [<ffffffff8158080d>] seq_read+0xdd/0x12d0 fs/seq_file.c:178
but task is already holding lock:
 (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81523c1e>] pipe_lock_nested fs/pipe.c:66 [inline]
 (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81523c1e>] pipe_lock+0x5e/0x70 fs/pipe.c:74
which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2
 (&pipe->mutex/1){+.+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:521 [inline]
       mutex_lock_nested+0xc0/0x900 kernel/locking/mutex.c:621
       __pipe_lock fs/pipe.c:87 [inline]
       fifo_open+0x15c/0x9e0 fs/pipe.c:921
       do_dentry_open+0x3ef/0xc90 fs/open.c:766
       vfs_open+0x11c/0x210 fs/open.c:879
       do_last fs/namei.c:3410 [inline]
       path_openat+0x542/0x2790 fs/namei.c:3534
       do_filp_open+0x197/0x270 fs/namei.c:3568
       do_open_execat+0x10f/0x640 fs/exec.c:844
       do_execveat_common.isra.14+0x687/0x1ed0 fs/exec.c:1723
       compat_do_execve fs/exec.c:1856 [inline]
       C_SYSC_execve fs/exec.c:1931 [inline]
       compat_SyS_execve+0x48/0x60 fs/exec.c:1927
       do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
       do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
       entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

-> #1
 (&sig->cred_guard_mutex){+.+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:521 [inline]
       mutex_lock_killable_nested+0xcc/0x9f0 kernel/locking/mutex.c:641
       lock_trace+0x44/0xc0 fs/proc/base.c:431
       proc_pid_syscall+0xa9/0x260 fs/proc/base.c:663
       proc_single_show+0xfd/0x170 fs/proc/base.c:785
       seq_read+0x4b6/0x12d0 fs/seq_file.c:240
       do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
       do_loop_readv_writev fs/read_write.c:707 [inline]
       do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
       vfs_readv+0x84/0xc0 fs/read_write.c:897
       kernel_readv fs/splice.c:363 [inline]
       default_file_splice_read+0x451/0x7f0 fs/splice.c:435
       do_splice_to+0x10c/0x170 fs/splice.c:899
       splice_direct_to_actor+0x23f/0x7e0 fs/splice.c:971
       do_splice_direct+0x1a3/0x270 fs/splice.c:1080
       do_sendfile+0x4f0/0xc30 fs/read_write.c:1393
       C_SYSC_sendfile fs/read_write.c:1475 [inline]
       compat_SyS_sendfile+0x143/0x160 fs/read_write.c:1458
       do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
       do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
       entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

-> #0
 (&p->lock){+.+.+.}:
       lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
       __mutex_lock_common kernel/locking/mutex.c:521 [inline]
       mutex_lock_nested+0xc0/0x900 kernel/locking/mutex.c:621
       seq_read+0xdd/0x12d0 fs/seq_file.c:178
       proc_reg_read+0xfd/0x180 fs/proc/inode.c:203
       do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
       do_loop_readv_writev fs/read_write.c:707 [inline]
       do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
       vfs_readv+0x84/0xc0 fs/read_write.c:897
       kernel_readv fs/splice.c:363 [inline]
       default_file_splice_read+0x451/0x7f0 fs/splice.c:435
       do_splice_to+0x10c/0x170 fs/splice.c:899
       do_splice fs/splice.c:1192 [inline]
       SYSC_splice fs/splice.c:1416 [inline]
       SyS_splice+0x10d2/0x14d0 fs/splice.c:1399
       do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
       do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
       entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

other info that might help us debug this:

Chain exists of:
  
&p->lock --> &sig->cred_guard_mutex --> &pipe->mutex/1


       CPU0                    CPU1
       ----                    ----
  lock(
&pipe->mutex/1);
&sig->cred_guard_mutex);
&pipe->mutex/1);
&p->lock);
 *** DEADLOCK ***

1 lock held by syz-executor.5/18542:
 #0: 
 (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81523c1e>] pipe_lock_nested fs/pipe.c:66 [inline]
 (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81523c1e>] pipe_lock+0x5e/0x70 fs/pipe.c:74
stack backtrace:
 0000000041b58ab3 ffffffff82e2b62b ffffffff813f6f66
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff813f7125>] panic+0x1bf/0x39f kernel/panic.c:179
 [<ffffffff813f7362>] __warn.cold.8+0x2f/0x2f kernel/panic.c:542
 [<ffffffff810dc02c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff81429420>] __alloc_pages_slowpath mm/page_alloc.c:3556 [inline]
 [<ffffffff81429420>] __alloc_pages_nodemask+0x13a0/0x1bd0 mm/page_alloc.c:3862
 [<ffffffff8147936a>] __alloc_pages include/linux/gfp.h:433 [inline]
 [<ffffffff8147936a>] __alloc_pages_node include/linux/gfp.h:446 [inline]
 [<ffffffff8147936a>] alloc_pages_node include/linux/gfp.h:460 [inline]
 [<ffffffff8147936a>] kmalloc_order+0x2a/0x70 mm/slab_common.c:1043
 [<ffffffff814793cf>] kmalloc_order_trace+0x1f/0x190 mm/slab_common.c:1054
 [<ffffffff814ee36e>] kmalloc_large include/linux/slab.h:422 [inline]
 [<ffffffff814ee36e>] __kmalloc+0x1ae/0x310 mm/slub.c:3730
 [<ffffffff81a20c19>] kmalloc include/linux/slab.h:495 [inline]
 [<ffffffff81a20c19>] str_read+0x39/0x150 security/selinux/ss/policydb.c:1100
 [<ffffffff81a21600>] type_read+0x230/0x410 security/selinux/ss/policydb.c:1501
 [<ffffffff81a2b1ea>] policydb_read+0xdba/0x2390 security/selinux/ss/policydb.c:2367
 [<ffffffff81a3ba84>] security_load_policy+0x264/0x9b0 security/selinux/ss/services.c:2067
 [<ffffffff81a1233b>] sel_write_load+0x19b/0xfa0 security/selinux/selinuxfs.c:522
 [<ffffffff81508085>] __vfs_write+0x115/0x580 fs/read_write.c:507
 [<ffffffff8150ab97>] vfs_write+0x187/0x520 fs/read_write.c:557
 [<ffffffff8150e9c9>] SYSC_write fs/read_write.c:604 [inline]
 [<ffffffff8150e9c9>] SyS_write+0xd9/0x1c0 fs/read_write.c:596
 [<ffffffff81006311>] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
 [<ffffffff81006311>] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
 [<ffffffff82818de0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137
CPU: 0 PID: 18542 Comm: syz-executor.5 Not tainted 4.9.141+ #23
 ffff880143aff268 ffffffff81b42e79 ffffffff83ca2fd0 ffffffff83caa290
 ffffffff83ca4920 ffff8801c9b167d0 ffff8801c9b15f00 ffff880143aff2b0
 ffffffff813fee40 0000000000000001 00000000c9b167b0 0000000000000001
Call Trace:
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff813fee40>] print_circular_bug.cold.36+0x2f7/0x432 kernel/locking/lockdep.c:1202
 [<ffffffff8120a539>] check_prev_add kernel/locking/lockdep.c:1828 [inline]
 [<ffffffff8120a539>] check_prevs_add kernel/locking/lockdep.c:1938 [inline]
 [<ffffffff8120a539>] validate_chain kernel/locking/lockdep.c:2265 [inline]
 [<ffffffff8120a539>] __lock_acquire+0x3189/0x4a10 kernel/locking/lockdep.c:3345
 [<ffffffff8120c8d0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
 [<ffffffff8280b250>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
 [<ffffffff8280b250>] mutex_lock_nested+0xc0/0x900 kernel/locking/mutex.c:621
 [<ffffffff8158080d>] seq_read+0xdd/0x12d0 fs/seq_file.c:178
 [<ffffffff8165c00d>] proc_reg_read+0xfd/0x180 fs/proc/inode.c:203
 [<ffffffff81509df5>] do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
 [<ffffffff8150b49e>] do_loop_readv_writev fs/read_write.c:707 [inline]
 [<ffffffff8150b49e>] do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
 [<ffffffff8150b764>] vfs_readv+0x84/0xc0 fs/read_write.c:897
 [<ffffffff815ac2a1>] kernel_readv fs/splice.c:363 [inline]
 [<ffffffff815ac2a1>] default_file_splice_read+0x451/0x7f0 fs/splice.c:435
 [<ffffffff815ab39c>] do_splice_to+0x10c/0x170 fs/splice.c:899
 [<ffffffff815b08f2>] do_splice fs/splice.c:1192 [inline]
 [<ffffffff815b08f2>] SYSC_splice fs/splice.c:1416 [inline]
 [<ffffffff815b08f2>] SyS_splice+0x10d2/0x14d0 fs/splice.c:1399
 [<ffffffff81006311>] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
 [<ffffffff81006311>] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
 [<ffffffff82818de0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137
Kernel Offset: disabled
Rebooting in 86400 seconds..