====================================================== [ INFO: possible circular locking dependency detected ] 4.9.84-ga9d0273 #44 Not tainted ------------------------------------------------------- syz-executor0/6877 is trying to acquire lock: (&mm->mmap_sem){++++++}, at: [] __might_fault+0xe4/0x1d0 mm/memory.c:3993 but task is already holding lock: (ashmem_mutex){+.+.+.}, at: [] ashmem_pin_unpin drivers/staging/android/ashmem.c:714 [inline] (ashmem_mutex){+.+.+.}, at: [] ashmem_ioctl+0x371/0xfe0 drivers/staging/android/ashmem.c:791 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: device eql entered promiscuous mode skbuff: bad partial csum: csum=0/3849 len=3712 lock_acquire+0x12e/0x410 kernel/locking/lockdep.c:3756 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_nested+0xbb/0x870 kernel/locking/mutex.c:621 ashmem_mmap+0x53/0x400 drivers/staging/android/ashmem.c:379 mmap_region+0x7dd/0xfd0 mm/mmap.c:1694 do_mmap+0x57b/0xbe0 mm/mmap.c:1473 do_mmap_pgoff include/linux/mm.h:2019 [inline] vm_mmap_pgoff+0x16b/0x1b0 mm/util.c:329 SYSC_mmap_pgoff mm/mmap.c:1523 [inline] SyS_mmap_pgoff+0x33f/0x560 mm/mmap.c:1481 SYSC_mmap arch/x86/kernel/sys_x86_64.c:95 [inline] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:86 do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x47/0xc5 check_prev_add kernel/locking/lockdep.c:1828 [inline] check_prevs_add kernel/locking/lockdep.c:1938 [inline] validate_chain kernel/locking/lockdep.c:2265 [inline] __lock_acquire+0x2bf9/0x3640 kernel/locking/lockdep.c:3345 lock_acquire+0x12e/0x410 kernel/locking/lockdep.c:3756 __might_fault+0x14a/0x1d0 mm/memory.c:3994 copy_from_user arch/x86/include/asm/uaccess.h:705 [inline] ashmem_pin_unpin drivers/staging/android/ashmem.c:719 [inline] ashmem_ioctl+0x3c0/0xfe0 drivers/staging/android/ashmem.c:791 vfs_ioctl fs/ioctl.c:43 [inline] do_vfs_ioctl+0x1aa/0x1140 fs/ioctl.c:679 SYSC_ioctl fs/ioctl.c:694 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x47/0xc5 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-executor0/6877: #0: (ashmem_mutex){+.+.+.}, at: [] ashmem_pin_unpin drivers/staging/android/ashmem.c:714 [inline] #0: (ashmem_mutex){+.+.+.}, at: [] ashmem_ioctl+0x371/0xfe0 drivers/staging/android/ashmem.c:791 stack backtrace: CPU: 0 PID: 6877 Comm: syz-executor0 Not tainted 4.9.84-ga9d0273 #44 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801d06ff908 ffffffff81d956b9 ffffffff853a2cd0 ffffffff853a2cd0 ffffffff853c3130 ffff8801d05ca0d8 ffff8801d05c9800 ffff8801d06ff950 ffffffff812387f1 ffff8801d05ca0d8 00000000d05ca0b0 ffff8801d05ca0d8 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_circular_bug+0x271/0x310 kernel/locking/lockdep.c:1202 [] check_prev_add kernel/locking/lockdep.c:1828 [inline] [] check_prevs_add kernel/locking/lockdep.c:1938 [inline] [] validate_chain kernel/locking/lockdep.c:2265 [inline] [] __lock_acquire+0x2bf9/0x3640 kernel/locking/lockdep.c:3345 [] lock_acquire+0x12e/0x410 kernel/locking/lockdep.c:3756 [] __might_fault+0x14a/0x1d0 mm/memory.c:3994 [] copy_from_user arch/x86/include/asm/uaccess.h:705 [inline] [] ashmem_pin_unpin drivers/staging/android/ashmem.c:719 [inline] [] ashmem_ioctl+0x3c0/0xfe0 drivers/staging/android/ashmem.c:791 [] vfs_ioctl fs/ioctl.c:43 [inline] [] do_vfs_ioctl+0x1aa/0x1140 fs/ioctl.c:679 [] SYSC_ioctl fs/ioctl.c:694 [inline] [] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 [] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x47/0xc5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=5195 sclass=netlink_route_socket pig=6920 comm=syz-executor2 audit_printk_skb: 70 callbacks suppressed audit: type=1400 audit(1519645239.894:50): avc: denied { write } for pid=6956 comm="syz-executor1" 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 l2tp_core: tunl 3: fd 19 wrong protocol, got 1, expected 17 l2tp_core: tunl 3: fd 20 wrong protocol, got 1, expected 17 SELinux: unrecognized netlink message: protocol=9 nlmsg_type=58 sclass=netlink_audit_socket pig=7065 comm=syz-executor0 audit: type=1400 audit(1519645240.274:51): avc: denied { read } for pid=7089 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_generic_socket permissive=1 audit: type=1400 audit(1519645241.514:52): avc: denied { setattr } for pid=7704 comm="syz-executor0" name="NETLINK" dev="sockfs" ino=18842 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(1519645241.604:53): avc: denied { getopt } for pid=7737 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_generic_socket permissive=1 netlink: 37 bytes leftover after parsing attributes in process `syz-executor5'. netlink: 37 bytes leftover after parsing attributes in process `syz-executor5'. audit: type=1400 audit(1519645242.264:54): avc: denied { getattr } for pid=8074 comm="syz-executor0" name="NETLINK" dev="sockfs" ino=19374 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(1519645242.514:55): avc: denied { setopt } for pid=8205 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_generic_socket permissive=1 audit: type=1400 audit(1519645242.964:56): avc: denied { bind } for pid=8468 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_generic_socket permissive=1 audit: type=1400 audit(1519645243.074:57): avc: denied { accept } for pid=8557 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_generic_socket permissive=1 audit: type=1400 audit(1519645243.114:58): avc: denied { setgid } for pid=8559 comm="syz-executor5" capability=6 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 netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9731 comm=syz-executor6 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9741 comm=syz-executor6 Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable 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(1519645246.364:59): avc: denied { setuid } for pid=10085 comm="syz-executor3" capability=7 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 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=532 sclass=netlink_route_socket pig=10100 comm=syz-executor0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=532 sclass=netlink_route_socket pig=10102 comm=syz-executor0 audit: type=1400 audit(1519645246.454:60): avc: denied { setopt } for pid=10108 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 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=50795 sclass=netlink_route_socket pig=10173 comm=syz-executor0 netlink: 8 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor0'. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=18452 sclass=netlink_route_socket pig=10441 comm=syz-executor0 netlink: 8 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor0'. syz-executor2 (10810) used greatest stack depth: 22688 bytes left SELinux: unrecognized netlink message: protocol=0 nlmsg_type=256 sclass=netlink_route_socket pig=10902 comm=syz-executor6 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=256 sclass=netlink_route_socket pig=10917 comm=syz-executor6 audit: type=1400 audit(1519645248.344:61): avc: denied { net_broadcast } for pid=10960 comm="syz-executor0" capability=11 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 FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 0 PID: 10972 Comm: syz-executor7 Not tainted 4.9.84-ga9d0273 #44 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801b1edf480 ffffffff81d956b9 ffff8801b1edf760 0000000000000000 ffff8801c4c20e90 ffff8801b1edf650 ffff8801c4c20d80 ffff8801b1edf678 ffffffff816626da ffffffff8107c65d ffff8801b1edf5d0 00000001d93bb067 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] handle_userfault+0xa3a/0x1310 fs/userfaultfd.c:323 [] do_anonymous_page mm/memory.c:2747 [inline] [] handle_pte_fault mm/memory.c:3488 [inline] [] __handle_mm_fault mm/memory.c:3577 [inline] [] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614 [] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1407 [] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1470 [] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:939 [] generic_perform_write+0x1dc/0x500 mm/filemap.c:2731 [] __generic_file_write_iter+0x348/0x570 mm/filemap.c:2866 [] generic_file_write_iter+0x2d5/0x600 mm/filemap.c:2894 [] new_sync_write fs/read_write.c:499 [inline] [] __vfs_write+0x4bf/0x680 fs/read_write.c:512 [] vfs_write+0x189/0x530 fs/read_write.c:560 [] SYSC_write fs/read_write.c:607 [inline] [] SyS_write+0xd9/0x1b0 fs/read_write.c:599 [] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x47/0xc5 FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 0 PID: 10972 Comm: syz-executor7 Not tainted 4.9.84-ga9d0273 #44 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801b1edf480 ffffffff81d956b9 ffff8801b1edf760 0000000000000000 ffff8801ba182d10 ffff8801b1edf650 ffff8801ba182c00 ffff8801b1edf678 ffffffff816626da ffff8801db221b80 ffff8801b1edf5d0 00000001d93bb067 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] handle_userfault+0xa3a/0x1310 fs/userfaultfd.c:323 [] do_anonymous_page mm/memory.c:2747 [inline] [] handle_pte_fault mm/memory.c:3488 [inline] [] __handle_mm_fault mm/memory.c:3577 [inline] [] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614 [] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1407 [] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1470 [] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:939 [] generic_perform_write+0x1dc/0x500 mm/filemap.c:2731 [] __generic_file_write_iter+0x348/0x570 mm/filemap.c:2866 [] generic_file_write_iter+0x2d5/0x600 mm/filemap.c:2894 [] new_sync_write fs/read_write.c:499 [inline] [] __vfs_write+0x4bf/0x680 fs/read_write.c:512 [] vfs_write+0x189/0x530 fs/read_write.c:560 [] SYSC_write fs/read_write.c:607 [inline] [] SyS_write+0xd9/0x1b0 fs/read_write.c:599 [] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x47/0xc5