====================================================== WARNING: possible circular locking dependency detected 4.16.0-rc4+ #254 Not tainted ------------------------------------------------------ syz-executor2/26720 is trying to acquire lock: (&mm->mmap_sem){++++}, at: [<000000002b6c2a06>] __might_fault+0xe0/0x1d0 mm/memory.c:4570 but task is already holding lock: (ashmem_mutex){+.+.}, at: [<00000000d9c21d21>] ashmem_pin_unpin drivers/staging/android/ashmem.c:705 [inline] (ashmem_mutex){+.+.}, at: [<00000000d9c21d21>] ashmem_ioctl+0x3db/0x11b0 drivers/staging/android/ashmem.c:782 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (ashmem_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 ashmem_mmap+0x53/0x410 drivers/staging/android/ashmem.c:362 call_mmap include/linux/fs.h:1786 [inline] mmap_region+0xa99/0x15a0 mm/mmap.c:1705 do_mmap+0x6c0/0xe00 mm/mmap.c:1483 do_mmap_pgoff include/linux/mm.h:2223 [inline] vm_mmap_pgoff+0x1de/0x280 mm/util.c:355 SYSC_mmap_pgoff mm/mmap.c:1533 [inline] SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1491 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 -> #0 (&mm->mmap_sem){++++}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __might_fault+0x13a/0x1d0 mm/memory.c:4571 _copy_from_user+0x2c/0x110 lib/usercopy.c:10 copy_from_user include/linux/uaccess.h:147 [inline] ashmem_pin_unpin drivers/staging/android/ashmem.c:710 [inline] ashmem_ioctl+0x438/0x11b0 drivers/staging/android/ashmem.c:782 compat_ashmem_ioctl+0x3e/0x50 drivers/staging/android/ashmem.c:813 C_SYSC_ioctl fs/compat_ioctl.c:1461 [inline] compat_SyS_ioctl+0x151/0x2a30 fs/compat_ioctl.c:1407 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 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-executor2/26720: #0: (ashmem_mutex){+.+.}, at: [<00000000d9c21d21>] ashmem_pin_unpin drivers/staging/android/ashmem.c:705 [inline] #0: (ashmem_mutex){+.+.}, at: [<00000000d9c21d21>] ashmem_ioctl+0x3db/0x11b0 drivers/staging/android/ashmem.c:782 stack backtrace: CPU: 0 PID: 26720 Comm: syz-executor2 Not tainted 4.16.0-rc4+ #254 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 print_circular_bug.isra.38+0x2cd/0x2dc kernel/locking/lockdep.c:1223 check_prev_add kernel/locking/lockdep.c:1863 [inline] check_prevs_add kernel/locking/lockdep.c:1976 [inline] validate_chain kernel/locking/lockdep.c:2417 [inline] __lock_acquire+0x30a8/0x3e00 kernel/locking/lockdep.c:3431 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __might_fault+0x13a/0x1d0 mm/memory.c:4571 _copy_from_user+0x2c/0x110 lib/usercopy.c:10 copy_from_user include/linux/uaccess.h:147 [inline] ashmem_pin_unpin drivers/staging/android/ashmem.c:710 [inline] ashmem_ioctl+0x438/0x11b0 drivers/staging/android/ashmem.c:782 compat_ashmem_ioctl+0x3e/0x50 drivers/staging/android/ashmem.c:813 C_SYSC_ioctl fs/compat_ioctl.c:1461 [inline] compat_SyS_ioctl+0x151/0x2a30 fs/compat_ioctl.c:1407 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f14c99 RSP: 002b:00000000f771009c EFLAGS: 00000286 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000007709 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 27299 Comm: syz-executor7 Not tainted 4.16.0-rc4+ #254 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:422 [inline] slab_alloc mm/slab.c:3365 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3539 getname_flags+0xcb/0x580 fs/namei.c:138 getname+0x19/0x20 fs/namei.c:209 do_sys_open+0x2e7/0x6d0 fs/open.c:1053 C_SYSC_open fs/open.c:1096 [inline] compat_SyS_open+0x2a/0x40 fs/open.c:1094 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fc1c99 RSP: 002b:00000000f77bcff4 EFLAGS: 00000292 ORIG_RAX: 0000000000000005 RAX: ffffffffffffffda RBX: 00000000f77bd02c RCX: 0000000000000002 RDX: 0000000000000000 RSI: 000000000813af00 RDI: 00000000f77bd02c RBP: 00000000f77bd158 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name fail_page_alloc, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 27313 Comm: syz-executor7 Not tainted 4.16.0-rc4+ #254 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_fail_alloc_page mm/page_alloc.c:2959 [inline] prepare_alloc_pages mm/page_alloc.c:4198 [inline] __alloc_pages_nodemask+0x327/0xdd0 mm/page_alloc.c:4237 __alloc_pages include/linux/gfp.h:456 [inline] __alloc_pages_node include/linux/gfp.h:469 [inline] kmem_getpages mm/slab.c:1410 [inline] cache_grow_begin+0x72/0x640 mm/slab.c:2665 cache_alloc_refill mm/slab.c:3032 [inline] ____cache_alloc mm/slab.c:3114 [inline] __do_cache_alloc mm/slab.c:3336 [inline] slab_alloc mm/slab.c:3371 [inline] kmem_cache_alloc+0x400/0x760 mm/slab.c:3539 getname_flags+0xcb/0x580 fs/namei.c:138 getname+0x19/0x20 fs/namei.c:209 do_sys_open+0x2e7/0x6d0 fs/open.c:1053 C_SYSC_open fs/open.c:1096 [inline] compat_SyS_open+0x2a/0x40 fs/open.c:1094 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fc1c99 RSP: 002b:00000000f77bcff4 EFLAGS: 00000292 ORIG_RAX: 0000000000000005 RAX: ffffffffffffffda RBX: 00000000f77bd02c RCX: 0000000000000002 RDX: 0000000000000000 RSI: 000000000813af00 RDI: 00000000f77bd02c RBP: 00000000f77bd158 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 27337 Comm: syz-executor7 Not tainted 4.16.0-rc4+ #254 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:422 [inline] slab_alloc mm/slab.c:3365 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3539 kmem_cache_zalloc include/linux/slab.h:691 [inline] file_alloc_security security/selinux/hooks.c:369 [inline] selinux_file_alloc_security+0xae/0x190 security/selinux/hooks.c:3454 security_file_alloc+0x6d/0xa0 security/security.c:873 get_empty_filp+0x189/0x4f0 fs/file_table.c:128 path_openat+0xed/0x3530 fs/namei.c:3495 do_filp_open+0x25b/0x3b0 fs/namei.c:3553 do_sys_open+0x502/0x6d0 fs/open.c:1059 C_SYSC_open fs/open.c:1096 [inline] compat_SyS_open+0x2a/0x40 fs/open.c:1094 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fc1c99 RSP: 002b:00000000f77bcff4 EFLAGS: 00000292 ORIG_RAX: 0000000000000005 RAX: ffffffffffffffda RBX: 00000000f77bd02c RCX: 0000000000000002 RDX: 0000000000000000 RSI: 000000000813af00 RDI: 00000000f77bd02c RBP: 00000000f77bd158 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 audit: type=1400 audit(1520414129.659:196): avc: denied { write } for pid=27382 comm="syz-executor7" name="net" dev="proc" ino=73386 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=dir permissive=1 audit: type=1400 audit(1520414129.670:197): avc: denied { add_name } for pid=27382 comm="syz-executor7" name="pfkey" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=dir permissive=1 audit: type=1400 audit(1520414129.676:198): avc: denied { create } for pid=27382 comm="syz-executor7" name="pfkey" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:insmod_t:s0 tclass=file permissive=1 QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl audit: type=1400 audit(1520414131.161:199): avc: denied { map } for pid=28025 comm="syz-executor4" path="socket:[75181]" dev="sockfs" ino=75181 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=tcp_socket permissive=1 QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl