======================================================
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket
[ INFO: possible circular locking dependency detected ]
4.4.120-gd63fdf6 #28 Not tainted
-------------------------------------------------------
syz-executor7/7861 is trying to acquire lock:
 (&mm->mmap_sem){++++++}, at: [   55.504672] SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket
[<ffffffff81495684>] __might_fault+0xe4/0x1d0 mm/memory.c:3809

but task is already holding lock:
 (ashmem_mutex){+.+.+.}, at: [<ffffffff82c628a7>] ashmem_pin_unpin drivers/staging/android/ashmem.c:701 [inline]
 (ashmem_mutex){+.+.+.}, at: [<ffffffff82c628a7>] ashmem_ioctl+0x367/0xfa0 drivers/staging/android/ashmem.c:778

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

       [<ffffffff8123d7ce>] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592
       [<ffffffff8376a39b>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
       [<ffffffff8376a39b>] mutex_lock_nested+0xbb/0x850 kernel/locking/mutex.c:621
       [<ffffffff82c61463>] ashmem_mmap+0x53/0x400 drivers/staging/android/ashmem.c:366
       [<ffffffff814b0e4f>] mmap_region+0x94f/0x1250 mm/mmap.c:1664
       [<ffffffff814b1c4d>] do_mmap+0x4fd/0x9d0 mm/mmap.c:1441
       [<ffffffff814700ce>] do_mmap_pgoff include/linux/mm.h:1915 [inline]
       [<ffffffff814700ce>] vm_mmap_pgoff+0x16e/0x1c0 mm/util.c:296
       [<ffffffff814afe1f>] SYSC_mmap_pgoff mm/mmap.c:1491 [inline]
       [<ffffffff814afe1f>] SyS_mmap_pgoff+0x33f/0x560 mm/mmap.c:1449
       [<ffffffff8101beb6>] SYSC_mmap arch/x86/kernel/sys_x86_64.c:95 [inline]
       [<ffffffff8101beb6>] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:86
       [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98

       [<ffffffff8123ab2f>] check_prev_add kernel/locking/lockdep.c:1853 [inline]
       [<ffffffff8123ab2f>] check_prevs_add kernel/locking/lockdep.c:1958 [inline]
       [<ffffffff8123ab2f>] validate_chain kernel/locking/lockdep.c:2144 [inline]
       [<ffffffff8123ab2f>] __lock_acquire+0x371f/0x4b50 kernel/locking/lockdep.c:3213
       [<ffffffff8123d7ce>] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592
       [<ffffffff814956ea>] __might_fault+0x14a/0x1d0 mm/memory.c:3810
       [<ffffffff82c628f4>] copy_from_user arch/x86/include/asm/uaccess.h:724 [inline]
       [<ffffffff82c628f4>] ashmem_pin_unpin drivers/staging/android/ashmem.c:706 [inline]
       [<ffffffff82c628f4>] ashmem_ioctl+0x3b4/0xfa0 drivers/staging/android/ashmem.c:778
       [<ffffffff81559daa>] vfs_ioctl fs/ioctl.c:43 [inline]
       [<ffffffff81559daa>] do_vfs_ioctl+0x7aa/0xee0 fs/ioctl.c:607
       [<ffffffff8155a56f>] SYSC_ioctl fs/ioctl.c:622 [inline]
       [<ffffffff8155a56f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613
       [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(ashmem_mutex);
                               lock(&mm->mmap_sem);
                               lock(ashmem_mutex);
  lock(&mm->mmap_sem);

 *** DEADLOCK ***

1 lock held by syz-executor7/7861:
 #0:  (ashmem_mutex){+.+.+.}, at: [<ffffffff82c628a7>] ashmem_pin_unpin drivers/staging/android/ashmem.c:701 [inline]
 #0:  (ashmem_mutex){+.+.+.}, at: [<ffffffff82c628a7>] ashmem_ioctl+0x367/0xfa0 drivers/staging/android/ashmem.c:778

stack backtrace:
CPU: 1 PID: 7861 Comm: syz-executor7 Not tainted 4.4.120-gd63fdf6 #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 3d72188b65fba8ce ffff8800b5fdf9b8 ffffffff81d0408d
 ffffffff851a0010 ffffffff851a0010 ffffffff851be7c0 ffff8800b5e568f8
 ffff8800b5e56000 ffff8800b5fdfa00 ffffffff81233ba1 ffff8800b5e568f8
Call Trace:
 [<ffffffff81d0408d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d0408d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff81233ba1>] print_circular_bug+0x271/0x310 kernel/locking/lockdep.c:1226
 [<ffffffff8123ab2f>] check_prev_add kernel/locking/lockdep.c:1853 [inline]
 [<ffffffff8123ab2f>] check_prevs_add kernel/locking/lockdep.c:1958 [inline]
 [<ffffffff8123ab2f>] validate_chain kernel/locking/lockdep.c:2144 [inline]
 [<ffffffff8123ab2f>] __lock_acquire+0x371f/0x4b50 kernel/locking/lockdep.c:3213
 [<ffffffff8123d7ce>] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592
 [<ffffffff814956ea>] __might_fault+0x14a/0x1d0 mm/memory.c:3810
 [<ffffffff82c628f4>] copy_from_user arch/x86/include/asm/uaccess.h:724 [inline]
 [<ffffffff82c628f4>] ashmem_pin_unpin drivers/staging/android/ashmem.c:706 [inline]
 [<ffffffff82c628f4>] ashmem_ioctl+0x3b4/0xfa0 drivers/staging/android/ashmem.c:778
 [<ffffffff81559daa>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff81559daa>] do_vfs_ioctl+0x7aa/0xee0 fs/ioctl.c:607
 [<ffffffff8155a56f>] SYSC_ioctl fs/ioctl.c:622 [inline]
 [<ffffffff8155a56f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613
 [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98
syz-executor5 uses obsolete (PF_INET,SOCK_PACKET)
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
audit: type=1400 audit(1521669602.887:22): avc:  denied  { read } for  pid=8368 comm="syz-executor7" path="socket:[18682]" dev="sockfs" ino=18682 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=54939 sclass=netlink_route_socket
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=54939 sclass=netlink_route_socket
netlink: 16 bytes leftover after parsing attributes in process `syz-executor1'.
audit: type=1400 audit(1521669603.297:23): avc:  denied  { getopt } for  pid=8468 comm="syz-executor5" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1
audit: type=1400 audit(1521669603.697:24): avc:  denied  { bind } for  pid=8523 comm="syz-executor6" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1
audit: type=1400 audit(1521669603.937:25): avc:  denied  { dyntransition } for  pid=8594 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0,c1 tclass=process permissive=1
audit: type=1326 audit(1521669603.977:26): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8611 comm="syz-executor7" exe="/root/syz-executor7" sig=9 arch=c000003e syscall=202 compat=0 ip=0x453e69 code=0x0
audit: type=1400 audit(1521669604.017:27): avc:  denied  { dyntransition } for  pid=8594 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0,c1 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0,c1 tclass=process permissive=1
audit: type=1326 audit(1521669604.057:28): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8611 comm="syz-executor7" exe="/root/syz-executor7" sig=9 arch=c000003e syscall=202 compat=0 ip=0x453e69 code=0x0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=28005 sclass=netlink_route_socket
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=28005 sclass=netlink_route_socket
audit: type=1400 audit(1521669604.597:29): avc:  denied  { ioctl } for  pid=8762 comm="syz-executor5" path="socket:[20111]" dev="sockfs" ino=20111 ioctlcmd=894b scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
BUG: using __this_cpu_read() in preemptible [00000000] code: syz-executor5/8806
caller is __this_cpu_preempt_check+0x1c/0x20 lib/smp_processor_id.c:62
CPU: 0 PID: 8806 Comm: syz-executor5 Not tainted 4.4.120-gd63fdf6 #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 d62fe7b429ae62c4 ffff8801c77cf6c8 ffffffff81d0408d
 0000000000000000 ffffffff839fe5a0 ffffffff83d0be20 ffff8800ae32b000
 0000000000000003 ffff8801c77cf708 ffffffff81d63fe4 ffff8801c77cf720
Call Trace:
 [<ffffffff81d0408d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d0408d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff81d63fe4>] check_preemption_disabled+0x1d4/0x200 lib/smp_processor_id.c:46
 [<ffffffff81d6404c>] __this_cpu_preempt_check+0x1c/0x20 lib/smp_processor_id.c:62
 [<ffffffff832e2f08>] ipcomp_alloc_tfms net/xfrm/xfrm_ipcomp.c:286 [inline]
 [<ffffffff832e2f08>] ipcomp_init_state+0x188/0x980 net/xfrm/xfrm_ipcomp.c:363
 [<ffffffff8324ac70>] ipcomp4_init_state+0xb0/0x7d0 net/ipv4/ipcomp.c:137
 [<ffffffff832c1817>] __xfrm_init_state+0x3e7/0xb30 net/xfrm/xfrm_state.c:2058
 [<ffffffff832c1f7a>] xfrm_init_state+0x1a/0x20 net/xfrm/xfrm_state.c:2084
 [<ffffffff8344681b>] pfkey_msg2xfrm_state net/key/af_key.c:1289 [inline]
 [<ffffffff8344681b>] pfkey_add+0x1fbb/0x3490 net/key/af_key.c:1506
 [<ffffffff8344a45b>] pfkey_process+0x68b/0x750 net/key/af_key.c:2834
 [<ffffffff8344bcb9>] pfkey_sendmsg+0x3a9/0x760 net/key/af_key.c:3678
 [<ffffffff82deba6a>] sock_sendmsg_nosec net/socket.c:625 [inline]
 [<ffffffff82deba6a>] sock_sendmsg+0xca/0x110 net/socket.c:635
 [<ffffffff82ded641>] ___sys_sendmsg+0x6c1/0x7c0 net/socket.c:1962
 [<ffffffff82def693>] __sys_sendmsg+0xd3/0x190 net/socket.c:1996
 [<ffffffff82def77d>] SYSC_sendmsg net/socket.c:2007 [inline]
 [<ffffffff82def77d>] SyS_sendmsg+0x2d/0x50 net/socket.c:2003
 [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98
netlink: 12 bytes leftover after parsing attributes in process `syz-executor7'.
netlink: 12 bytes leftover after parsing attributes in process `syz-executor7'.
device lo entered promiscuous mode
device syz_tun entered promiscuous mode
audit: type=1400 audit(1521669606.367:30): avc:  denied  { attach_queue } for  pid=9283 comm="syz-executor0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=tun_socket permissive=1
device syz_tun left promiscuous mode
device lo left promiscuous mode
netlink: 92 bytes leftover after parsing attributes in process `syz-executor0'.
binder: 9864:9878 BC_FREE_BUFFER u0000000000000000 no match
binder: 9876:9882 ioctl c0306201 2001bfd0 returned -14
binder: 9876:9889 ioctl c0306201 2001bfd0 returned -14
binder: BINDER_SET_CONTEXT_MGR already set
binder: 9864:9888 ioctl 40046207 0 returned -16
binder_alloc: 9864: binder_alloc_buf, no vma
binder: 9864:9888 BC_FREE_BUFFER u0000000000000000 no match
binder: 9864:9878 transaction failed 29189/-3, size 0-0 line 3128
binder: undelivered TRANSACTION_ERROR: 29189
binder: release 9864:9878 transaction 39 out, still active
binder: undelivered TRANSACTION_COMPLETE
binder: send failed reply for transaction 39, target dead
binder: 9995:10006 unknown command 1325687557
binder: 9995:10006 ioctl c0306201 20007000 returned -22
binder: BINDER_SET_CONTEXT_MGR already set
netlink: 60 bytes leftover after parsing attributes in process `syz-executor4'.
binder: 9995:10006 ioctl 40046207 0 returned -16
binder: 9995:10006 IncRefs 0 refcount change on invalid ref 1 ret -22
binder: BINDER_SET_CONTEXT_MGR already set
binder: 9995:10006 ioctl 40046207 0 returned -16
binder: 9995:10006 unknown command 1325687557
binder: 9995:10006 ioctl c0306201 20007000 returned -22
binder: 9995:10006 IncRefs 0 refcount change on invalid ref 1 ret -22
binder: 10001:10041 ioctl c0306201 20012000 returned -14
binder: 10001:10027 ioctl c0306201 200000c0 returned -14
binder: 10001:10008 ioctl c0306201 200000c0 returned -14