================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3888/0x5140 kernel/locking/lockdep.c:3314 Read of size 8 at addr ffff8801cda6e158 by task syz-executor4/4585 CPU: 1 PID: 4585 Comm: syz-executor4 Not tainted 4.17.0+ #93 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __lock_acquire+0x3888/0x5140 kernel/locking/lockdep.c:3314 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3924 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 finish_wait+0x116/0x420 kernel/sched/wait.c:364 pipe_wait+0x1b4/0x2a0 fs/pipe.c:117 pipe_read+0x37c/0x940 fs/pipe.c:333 call_read_iter include/linux/fs.h:1787 [inline] new_sync_read fs/read_write.c:406 [inline] __vfs_read+0x6c0/0xa60 fs/read_write.c:418 vfs_read+0x17f/0x3d0 fs/read_write.c:452 kernel_read+0xab/0x120 fs/read_write.c:431 __bpfilter_process_sockopt+0x238/0x35b net/bpfilter/bpfilter_kern.c:74 bpfilter_mbox_request+0x4d/0xb0 net/ipv4/bpfilter/sockopt.c:25 bpfilter_ip_get_sockopt+0x6b/0x90 net/ipv4/bpfilter/sockopt.c:42 ip_getsockopt+0x238/0x2a0 net/ipv4/ip_sockglue.c:1563 tcp_getsockopt+0x93/0xe0 net/ipv4/tcp.c:3532 sock_common_getsockopt+0x9a/0xe0 net/core/sock.c:3012 __sys_getsockopt+0x1a5/0x370 net/socket.c:1972 __do_sys_getsockopt net/socket.c:1983 [inline] __se_sys_getsockopt net/socket.c:1980 [inline] __x64_sys_getsockopt+0xbe/0x150 net/socket.c:1980 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4584ea Code: b8 34 01 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 1d 8f fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 fa 8e fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:0000000000a3e328 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 0000000000a3e350 RCX: 00000000004584ea RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000013 RBP: 0000000000706f20 R08: 0000000000a3e34c R09: 0000000000004000 R10: 0000000000a3e350 R11: 0000000000000246 R12: 0000000000000013 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000704d60 Allocated by task 2223: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:706 [inline] alloc_pipe_info+0x16d/0x580 fs/pipe.c:636 get_pipe_inode fs/pipe.c:715 [inline] create_pipe_files+0xd0/0x940 fs/pipe.c:748 umh_pipe_setup+0x17b/0x430 kernel/umh.c:442 call_usermodehelper_exec_async+0x3c0/0x9e0 kernel/umh.c:93 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Freed by task 2223: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 free_pipe_info+0x253/0x300 fs/pipe.c:687 put_pipe_info+0xd0/0xf0 fs/pipe.c:559 pipe_release+0x1de/0x270 fs/pipe.c:580 __fput+0x353/0x890 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x1e4/0x290 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x1aee/0x2730 kernel/exit.c:865 do_group_exit+0x16f/0x430 kernel/exit.c:968 get_signal+0x886/0x1960 kernel/signal.c:2478 do_signal+0x98/0x2040 arch/x86/kernel/signal.c:810 exit_to_usermode_loop+0x28a/0x310 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801cda6e0c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 152 bytes inside of 512-byte region [ffff8801cda6e0c0, ffff8801cda6e2c0) The buggy address belongs to the page: page:ffffea0007369b80 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea00075ab1c8 ffffea0007637748 ffff8801da800940 raw: 0000000000000000 ffff8801cda6e0c0 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cda6e000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801cda6e080: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8801cda6e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801cda6e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cda6e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================