====================================================== [ INFO: possible circular locking dependency detected ] 4.4.120-gd63fdf6 #28 Not tainted ------------------------------------------------------- syz-executor4/14887 is trying to acquire lock: (&mm->mmap_sem){++++++}, at: [] __might_fault+0xe4/0x1d0 mm/memory.c:3809 but task is already holding lock: (ashmem_mutex){+.+.+.}, at: [] ashmem_pin_unpin drivers/staging/android/ashmem.c:701 [inline] (ashmem_mutex){+.+.+.}, at: [] 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: [] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592 [] __mutex_lock_common kernel/locking/mutex.c:521 [inline] [] mutex_lock_nested+0xbb/0x850 kernel/locking/mutex.c:621 [] ashmem_mmap+0x53/0x400 drivers/staging/android/ashmem.c:366 [] mmap_region+0x94f/0x1250 mm/mmap.c:1664 [] do_mmap+0x4fd/0x9d0 mm/mmap.c:1441 [] do_mmap_pgoff include/linux/mm.h:1915 [inline] [] vm_mmap_pgoff+0x16e/0x1c0 mm/util.c:296 [] SYSC_mmap_pgoff mm/mmap.c:1491 [inline] [] SyS_mmap_pgoff+0x33f/0x560 mm/mmap.c:1449 [] SYSC_mmap arch/x86/kernel/sys_x86_64.c:95 [inline] [] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:86 [] entry_SYSCALL_64_fastpath+0x1c/0x98 [] check_prev_add kernel/locking/lockdep.c:1853 [inline] [] check_prevs_add kernel/locking/lockdep.c:1958 [inline] [] validate_chain kernel/locking/lockdep.c:2144 [inline] [] __lock_acquire+0x371f/0x4b50 kernel/locking/lockdep.c:3213 [] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592 [] __might_fault+0x14a/0x1d0 mm/memory.c:3810 [] copy_from_user arch/x86/include/asm/uaccess.h:724 [inline] [] ashmem_pin_unpin drivers/staging/android/ashmem.c:706 [inline] [] ashmem_ioctl+0x3b4/0xfa0 drivers/staging/android/ashmem.c:778 [] vfs_ioctl fs/ioctl.c:43 [inline] [] do_vfs_ioctl+0x7aa/0xee0 fs/ioctl.c:607 [] SYSC_ioctl fs/ioctl.c:622 [inline] [] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613 [] 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-executor4/14887: #0: (ashmem_mutex){+.+.+.}, at: [] ashmem_pin_unpin drivers/staging/android/ashmem.c:701 [inline] #0: (ashmem_mutex){+.+.+.}, at: [] ashmem_ioctl+0x367/0xfa0 drivers/staging/android/ashmem.c:778 stack backtrace: CPU: 0 PID: 14887 Comm: syz-executor4 Not tainted 4.4.120-gd63fdf6 #28 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 e1af1a86e46c5716 ffff8801cf3af9b8 ffffffff81d0408d ffffffff8519fe60 ffffffff8519fe60 ffffffff851be610 ffff8800bb85d0f8 ffff8800bb85c800 ffff8801cf3afa00 ffffffff81233ba1 ffff8800bb85d0f8 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x124 lib/dump_stack.c:51 [] print_circular_bug+0x271/0x310 kernel/locking/lockdep.c:1226 [] check_prev_add kernel/locking/lockdep.c:1853 [inline] [] check_prevs_add kernel/locking/lockdep.c:1958 [inline] [] validate_chain kernel/locking/lockdep.c:2144 [inline] [] __lock_acquire+0x371f/0x4b50 kernel/locking/lockdep.c:3213 [] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592 [] __might_fault+0x14a/0x1d0 mm/memory.c:3810 [] copy_from_user arch/x86/include/asm/uaccess.h:724 [inline] [] ashmem_pin_unpin drivers/staging/android/ashmem.c:706 [inline] [] ashmem_ioctl+0x3b4/0xfa0 drivers/staging/android/ashmem.c:778 [] vfs_ioctl fs/ioctl.c:43 [inline] [] do_vfs_ioctl+0x7aa/0xee0 fs/ioctl.c:607 [] SYSC_ioctl fs/ioctl.c:622 [inline] [] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613 [] entry_SYSCALL_64_fastpath+0x1c/0x98 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=39 sclass=netlink_route_socket SELinux: unrecognized netlink message: protocol=0 nlmsg_type=39 sclass=netlink_route_socket TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1326 audit(1520655223.161:139): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15035 comm="syz-executor2" exe="/root/syz-executor2" sig=9 arch=c000003e syscall=202 compat=0 ip=0x453e69 code=0x0 audit: type=1326 audit(1520655223.291:140): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15035 comm="syz-executor2" exe="/root/syz-executor2" sig=9 arch=c000003e syscall=202 compat=0 ip=0x453e69 code=0x0 audit: type=1400 audit(1520655224.331:141): avc: denied { create } for pid=15195 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=netlink_rdma_socket permissive=1 audit: type=1400 audit(1520655224.451:142): avc: denied { create } for pid=15195 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=netlink_rdma_socket permissive=1 netlink: 64 bytes leftover after parsing attributes in process `syz-executor4'. audit: type=1400 audit(1520655225.081:143): avc: denied { create } for pid=15287 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=netlink_netfilter_socket permissive=1 audit: type=1400 audit(1520655225.151:144): avc: denied { create } for pid=15287 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=netlink_netfilter_socket permissive=1 device syz_tun entered promiscuous mode device syz_tun left promiscuous mode device syz_tun entered promiscuous mode device syz_tun left promiscuous mode audit: type=1400 audit(1520655226.001:145): avc: denied { create } for pid=15407 comm="syz-executor2" 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 audit: type=1400 audit(1520655226.141:146): avc: denied { write } for pid=15407 comm="syz-executor2" 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 audit: type=1400 audit(1520655226.161:147): avc: denied { create } for pid=15407 comm="syz-executor2" 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 audit: type=1326 audit(1520655226.541:148): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15430 comm="syz-executor7" exe="/root/syz-executor7" sig=9 arch=c000003e syscall=202 compat=0 ip=0x453e69 code=0x0 binder_alloc: binder_alloc_mmap_handler: 15465 20000000-20002000 already mapped failed -16 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket syz-executor2 (15543): /proc/15541/oom_adj is deprecated, please use /proc/15541/oom_score_adj instead. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. device syz_tun entered promiscuous mode device syz_tun left promiscuous mode netlink: 28 bytes leftover after parsing attributes in process `syz-executor1'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor1'. binder_alloc: 15635: binder_alloc_buf, no vma binder: 15635:15642 unknown command -1260301296 binder: 15635:15642 ioctl c0306201 20000580 returned -22 binder: 15635:15638 transaction failed 29189/-3, size 40-8 line 3128 binder: BINDER_SET_CONTEXT_MGR already set binder: 15635:15655 ioctl 40046207 0 returned -16 binder: 15635:15651 got transaction with invalid offsets ptr binder: 15635:15651 transaction failed 29201/-14, size 40-8 line 3156 binder: undelivered TRANSACTION_ERROR: 29201 binder: undelivered TRANSACTION_ERROR: 29189 IPVS: length: 24 != 8 binder_alloc: binder_alloc_mmap_handler: 15782 20000000-20002000 already mapped failed -16 binder: 15852:15864 transaction failed 29189/-22, size 0-0 line 3005 binder: 15852:15871 transaction failed 29189/-22, size 0-0 line 3005 binder: undelivered TRANSACTION_ERROR: 29189 binder: undelivered TRANSACTION_ERROR: 29189 audit_printk_skb: 12 callbacks suppressed audit: type=1400 audit(1520655229.901:153): avc: denied { create } for pid=15887 comm="syz-executor7" 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 audit: type=1400 audit(1520655229.971:154): avc: denied { create } for pid=15887 comm="syz-executor7" 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 audit: type=1400 audit(1520655230.211:155): avc: denied { create } for pid=15935 comm="syz-executor3" 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(1520655230.301:156): avc: denied { create } for pid=15935 comm="syz-executor3" 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 netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. audit: type=1400 audit(1520655230.661:157): avc: denied { set_context_mgr } for pid=15984 comm="syz-executor3" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=binder permissive=1 audit: type=1400 audit(1520655230.681:158): avc: denied { create } for pid=15990 comm="syz-executor7" 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 binder: 15984:15998 ioctl c0306201 2075afd0 returned -14 binder: 15984:16010 ioctl c0306201 2075afd0 returned -14 audit: type=1400 audit(1520655230.811:159): avc: denied { create } for pid=15990 comm="syz-executor7" 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 binder: BINDER_SET_CONTEXT_MGR already set binder: 15984:16004 ioctl 40046207 0 returned -16 binder: BINDER_SET_CONTEXT_MGR already set binder: 16025:16026 ioctl 40046207 0 returned -16 binder: 16025:16026 unknown command 1145594129 binder: 16025:16026 ioctl c0306201 20007000 returned -22 audit: type=1400 audit(1520655231.011:160): avc: denied { set_context_mgr } for pid=16025 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=binder permissive=1 binder: 16025:16026 unknown command 1145594129 binder: 16025:16026 ioctl c0306201 20007000 returned -22 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=2577 sclass=netlink_route_socket