bpfilter: read fail -512
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BUG: KASAN: use-after-free in __lock_acquire+0x3888/0x5140 kernel/locking/lockdep.c:3314
Read of size 8 at addr ffff8801cda903a0 by task syz-executor1/4576

CPU: 1 PID: 4576 Comm: syz-executor1 Not tainted 4.17.0+ #115
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
 __mutex_lock_common kernel/locking/mutex.c:757 [inline]
 __mutex_lock+0x16d/0x17f0 kernel/locking/mutex.c:894
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909
 __pipe_lock fs/pipe.c:83 [inline]
 pipe_read+0xc9/0x940 fs/pipe.c:260
 call_read_iter include/linux/fs.h:1785 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x696/0xa50 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
 compat_ip_getsockopt+0x256/0x2f0 net/ipv4/ip_sockglue.c:1600
 inet_csk_compat_getsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1023
 compat_tcp_getsockopt+0x49/0x80 net/ipv4/tcp.c:3543
 compat_sock_common_getsockopt+0xb4/0x150 net/core/sock.c:3023
 __compat_sys_getsockopt+0x1ae/0x880 net/compat.c:532
 __do_compat_sys_socketcall net/compat.c:916 [inline]
 __se_compat_sys_socketcall net/compat.c:844 [inline]
 __ia32_compat_sys_socketcall+0xcd1/0x1070 net/compat.c:844
 do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline]
 do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f27cb9
Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 1c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 
RSP: 002b:000000000845e340 EFLAGS: 00000206 ORIG_RAX: 0000000000000066
RAX: ffffffffffffffda RBX: 000000000000000f RCX: 000000000845e35c
RDX: 000000000845e3b4 RSI: 000000000845e3b4 RDI: 000000000845e408
RBP: 000000000811fe18 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 2224:
 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 2224:
 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
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801cda90340
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 96 bytes inside of
 512-byte region [ffff8801cda90340, ffff8801cda90540)
The buggy address belongs to the page:
page:ffffea000736a400 count:1 mapcount:0 mapping:ffff8801da800940 index:0xffff8801cda90840
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea000708c448 ffffea0006f90888 ffff8801da800940
raw: ffff8801cda90840 ffff8801cda900c0 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801cda90280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8801cda90300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff8801cda90380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff8801cda90400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801cda90480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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