EXT4-fs (loop5): Unsupported filesystem blocksize 0 (1923657432 log_block_size) SELinux: unrecognized netlink message: protocol=9 nlmsg_type=0 sclass=netlink_audit_socket pig=6636 comm=syz-executor.1 EXT4-fs (loop5): mounting ext3 file system using the ext4 subsystem EXT4-fs (loop5): Unsupported filesystem blocksize 0 (1923657432 log_block_size) ====================================================== [ INFO: possible circular locking dependency detected ] 4.9.202+ #0 Not tainted ------------------------------------------------------- syz-executor.3/6594 is trying to acquire lock: (&mm->mmap_sem){++++++}, at: [<000000002dc56834>] __do_page_fault+0x7bd/0xa60 arch/x86/mm/fault.c:1337 but task is already holding lock: (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000fda2b723>] inode_lock include/linux/fs.h:771 [inline] (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000fda2b723>] generic_file_write_iter+0x9a/0x630 mm/filemap.c:3090 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#10){+.+.+.}: lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3759 down_write+0x41/0xa0 kernel/locking/rwsem.c:52 inode_lock include/linux/fs.h:771 [inline] shmem_fallocate+0x143/0xab0 mm/shmem.c:2683 ashmem_shrink_scan drivers/staging/android/ashmem.c:462 [inline] ashmem_shrink_scan+0x1c3/0x4c0 drivers/staging/android/ashmem.c:446 ashmem_ioctl+0x29b/0xdd0 drivers/staging/android/ashmem.c:804 vfs_ioctl fs/ioctl.c:43 [inline] file_ioctl fs/ioctl.c:493 [inline] do_vfs_ioctl+0xb87/0x11d0 fs/ioctl.c:677 SYSC_ioctl fs/ioctl.c:694 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 entry_SYSCALL_64_after_swapgs+0x5d/0xdb -> #1 (ashmem_mutex){+.+.+.}: lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3759 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_nested+0xc7/0x920 kernel/locking/mutex.c:621 ashmem_mmap+0x53/0x470 drivers/staging/android/ashmem.c:378 mmap_region+0x7e7/0xfa0 mm/mmap.c:1726 do_mmap+0x539/0xbc0 mm/mmap.c:1505 do_mmap_pgoff include/linux/mm.h:2066 [inline] vm_mmap_pgoff+0x179/0x1c0 mm/util.c:329 SYSC_mmap_pgoff mm/mmap.c:1555 [inline] SyS_mmap_pgoff+0xfa/0x1b0 mm/mmap.c:1513 SYSC_mmap arch/x86/kernel/sys_x86_64.c:96 [inline] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:87 do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 entry_SYSCALL_64_after_swapgs+0x5d/0xdb -> #0 (&mm->mmap_sem){++++++}: 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+0x2d22/0x4390 kernel/locking/lockdep.c:3345 lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3759 down_read+0x44/0xb0 kernel/locking/rwsem.c:22 __do_page_fault+0x7bd/0xa60 arch/x86/mm/fault.c:1337 do_page_fault+0x28/0x30 arch/x86/mm/fault.c:1464 page_fault+0x25/0x30 arch/x86/entry/entry_64.S:956 generic_perform_write+0x1b6/0x500 mm/filemap.c:2930 __generic_file_write_iter+0x340/0x530 mm/filemap.c:3065 generic_file_write_iter+0x38a/0x630 mm/filemap.c:3093 new_sync_write fs/read_write.c:498 [inline] __vfs_write+0x3c1/0x560 fs/read_write.c:511 vfs_write+0x185/0x520 fs/read_write.c:559 SYSC_write fs/read_write.c:607 [inline] SyS_write+0x121/0x270 fs/read_write.c:599 do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 entry_SYSCALL_64_after_swapgs+0x5d/0xdb other info that might help us debug this: Chain exists of: &mm->mmap_sem --> ashmem_mutex --> &sb->s_type->i_mutex_key#10 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#10); lock(ashmem_mutex); lock(&sb->s_type->i_mutex_key#10); lock(&mm->mmap_sem); *** DEADLOCK *** 2 locks held by syz-executor.3/6594: #0: (sb_writers#6){.+.+.+}, at: [<000000005482490b>] file_start_write include/linux/fs.h:2645 [inline] #0: (sb_writers#6){.+.+.+}, at: [<000000005482490b>] vfs_write+0x3e9/0x520 fs/read_write.c:558 #1: (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000fda2b723>] inode_lock include/linux/fs.h:771 [inline] #1: (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000fda2b723>] generic_file_write_iter+0x9a/0x630 mm/filemap.c:3090 stack backtrace: CPU: 1 PID: 6594 Comm: syz-executor.3 Not tainted 4.9.202+ #0 ffff88019ec475d8 ffffffff81b55d2b ffffffff83cae4c0 ffffffff83cb7e50 ffffffff83cf2890 ffffffff8424ff40 ffff88019f5d4740 ffff88019ec47630 ffffffff81406d6a dffffc0000000000 ffffffff840642c0 ffff88019f5d5040 Call Trace: [<000000000288d809>] __dump_stack lib/dump_stack.c:15 [inline] [<000000000288d809>] dump_stack+0xcb/0x130 lib/dump_stack.c:56 [<000000001f864149>] print_circular_bug.cold+0x2f6/0x454 kernel/locking/lockdep.c:1202 [<00000000f6c67302>] check_prev_add kernel/locking/lockdep.c:1828 [inline] [<00000000f6c67302>] check_prevs_add kernel/locking/lockdep.c:1938 [inline] [<00000000f6c67302>] validate_chain kernel/locking/lockdep.c:2265 [inline] [<00000000f6c67302>] __lock_acquire+0x2d22/0x4390 kernel/locking/lockdep.c:3345 [<0000000085155b19>] lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3759 [<00000000823eaaf3>] down_read+0x44/0xb0 kernel/locking/rwsem.c:22 [<000000002dc56834>] __do_page_fault+0x7bd/0xa60 arch/x86/mm/fault.c:1337 [<000000006917a343>] do_page_fault+0x28/0x30 arch/x86/mm/fault.c:1464 [<00000000cd1db3eb>] page_fault+0x25/0x30 arch/x86/entry/entry_64.S:956 [<0000000055d957fb>] generic_perform_write+0x1b6/0x500 mm/filemap.c:2930 [<000000009e7a7fb9>] __generic_file_write_iter+0x340/0x530 mm/filemap.c:3065 [<00000000f5ea52f4>] generic_file_write_iter+0x38a/0x630 mm/filemap.c:3093 [<000000000adecd63>] new_sync_write fs/read_write.c:498 [inline] [<000000000adecd63>] __vfs_write+0x3c1/0x560 fs/read_write.c:511 [<00000000af2a5b5a>] vfs_write+0x185/0x520 fs/read_write.c:559 [<00000000a62a24d5>] SYSC_write fs/read_write.c:607 [inline] [<00000000a62a24d5>] SyS_write+0x121/0x270 fs/read_write.c:599 [<00000000ec6be136>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 [<00000000a84bbfa1>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb SELinux: unrecognized netlink message: protocol=9 nlmsg_type=0 sclass=netlink_audit_socket pig=6713 comm=syz-executor.1 SELinux: unrecognized netlink message: protocol=9 nlmsg_type=0 sclass=netlink_audit_socket pig=6713 comm=syz-executor.1 SELinux: unrecognized netlink message: protocol=9 nlmsg_type=0 sclass=netlink_audit_socket pig=6713 comm=syz-executor.1 SELinux: unrecognized netlink message: protocol=9 nlmsg_type=0 sclass=netlink_audit_socket pig=6713 comm=syz-executor.1 selinux_nlmsg_perm: 138 callbacks suppressed SELinux: unrecognized netlink message: protocol=0 nlmsg_type=784 sclass=netlink_route_socket pig=6903 comm=syz-executor.3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=784 sclass=netlink_route_socket pig=6906 comm=syz-executor.3 ip6_tunnel: l xmit: Local address not yet configured! ip6_tunnel: l xmit: Local address not yet configured! ip6_tunnel: l xmit: Local address not yet configured! ip6_tunnel: l xmit: Local address not yet configured! ip6_tunnel: l xmit: Local address not yet configured! ip6_tunnel: l xmit: Local address not yet configured! ip6_tunnel: l xmit: Local address not yet configured!