================================================================== BUG: KASAN: use-after-free in __list_add_valid+0xb1/0xd0 lib/list_debug.c:23 Read of size 8 at addr ffff8801c8ce51f0 by task syz-executor0/4227 CPU: 0 PID: 4227 Comm: syz-executor0 Not tainted 4.13.0-rc7+ #65 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 __list_add_valid+0xb1/0xd0 lib/list_debug.c:23 __list_add_rcu include/linux/rculist.h:51 [inline] list_add_rcu include/linux/rculist.h:78 [inline] dev_add_pack+0x113/0x2b0 net/core/dev.c:410 register_prot_hook.part.49+0x95/0xb0 net/packet/af_packet.c:348 register_prot_hook include/linux/compiler.h:279 [inline] packet_create+0x81a/0xb00 net/packet/af_packet.c:3253 __sock_create+0x4d4/0x850 net/socket.c:1248 sock_create net/socket.c:1288 [inline] SYSC_socket net/socket.c:1318 [inline] SyS_socket+0xeb/0x200 net/socket.c:1298 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x451e59 RSP: 002b:00007f7c22bc0c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 0000000000451e59 RDX: 0000000000000008 RSI: 0000000000080003 RDI: 0000000000000011 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004bb419 R13: 00000000ffffffff R14: ffffffffffffffff R15: 0000000000000001 Allocated by task 4087: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x12f/0x740 mm/slab.c:3627 kmalloc include/linux/slab.h:493 [inline] kzalloc include/linux/slab.h:666 [inline] fanout_add+0xa50/0x1190 net/packet/af_packet.c:1735 packet_setsockopt+0xfdc/0x1e80 net/packet/af_packet.c:3797 SYSC_setsockopt net/socket.c:1838 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1817 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 4232: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 packet_release+0xa8f/0xd70 net/packet/af_packet.c:3035 sock_release+0x8d/0x1e0 net/socket.c:597 sock_close+0x16/0x20 net/socket.c:1112 __fput+0x327/0x7e0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:246 task_work_run+0x18a/0x260 kernel/task_work.c:116 exit_task_work include/linux/task_work.h:21 [inline] do_exit+0xa3a/0x1b10 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:969 get_signal+0x7e8/0x17e0 kernel/signal.c:2334 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:808 exit_to_usermode_loop+0x224/0x300 arch/x86/entry/common.c:157 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath+0x3a7/0x450 arch/x86/entry/common.c:263 entry_SYSCALL_64_fastpath+0xbc/0xbe The buggy address belongs to the object at ffff8801c8ce4940 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 2224 bytes inside of 4096-byte region [ffff8801c8ce4940, ffff8801c8ce5940) The buggy address belongs to the page: page:ffffea0007233900 count:1 mapcount:0 mapping:ffff8801c8ce4940 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801c8ce4940 0000000000000000 0000000100000001 raw: ffffea000725fc20 ffffea0007233a20 ffff8801dac00dc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c8ce5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c8ce5100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c8ce5180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c8ce5200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c8ce5280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================