================================================================== BUG: KASAN: use-after-free in deliver_ptype_list_skb net/core/dev.c:1871 [inline] BUG: KASAN: use-after-free in __netif_receive_skb_core+0x2be3/0x33d0 net/core/dev.c:4401 Read of size 2 at addr ffff8801c030cec0 by task syzkaller358977/2993 CPU: 0 PID: 2993 Comm: syzkaller358977 Not tainted 4.13.0-next-20170908+ #18 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_load2_noabort+0x14/0x20 mm/kasan/report.c:428 deliver_ptype_list_skb net/core/dev.c:1871 [inline] __netif_receive_skb_core+0x2be3/0x33d0 net/core/dev.c:4401 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4456 netif_receive_skb_internal+0x10b/0x5e0 net/core/dev.c:4527 napi_skb_finish net/core/dev.c:4888 [inline] napi_gro_receive+0x3d0/0x500 net/core/dev.c:4919 receive_buf+0xcc5/0x51f0 drivers/net/virtio_net.c:841 virtnet_receive drivers/net/virtio_net.c:1087 [inline] virtnet_poll+0x304/0xad0 drivers/net/virtio_net.c:1168 napi_poll net/core/dev.c:5530 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5596 __do_softirq+0x2bb/0xbd0 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1d3/0x210 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:638 [inline] do_IRQ+0xf6/0x190 arch/x86/kernel/irq.c:253 common_interrupt+0x9d/0x9d arch/x86/entry/entry_64.S:598 RIP: 0033:0x4054ea RSP: 002b:00007ffc78384098 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff6e RAX: 0000000000000000 RBX: 0000000000001e75 RCX: 000000000000a7f8 RDX: 0000000040000001 RSI: 00007ffc783840ac RDI: 00000000ffffffff RBP: 000000000000abb0 R08: 0000000000000bb1 R09: 0000000000e1f880 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001e75 R13: 00000000004070f0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7791: 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+0x136/0x750 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:1733 packet_setsockopt+0xfdc/0x1e80 net/packet/af_packet.c:3795 SYSC_setsockopt net/socket.c:1852 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1831 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 7713: 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:3033 sock_release+0x8d/0x1e0 net/socket.c:597 sock_close+0x16/0x20 net/socket.c:1126 __fput+0x333/0x7f0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:244 task_work_run+0x199/0x270 kernel/task_work.c:112 exit_task_work include/linux/task_work.h:21 [inline] do_exit+0xa52/0x1b40 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:968 SYSC_exit_group kernel/exit.c:979 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:977 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801c030c640 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 2176 bytes inside of 4096-byte region [ffff8801c030c640, ffff8801c030d640) The buggy address belongs to the page: page:ffffea000700c300 count:1 mapcount:0 mapping:ffff8801c030c640 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801c030c640 0000000000000000 0000000100000001 raw: ffffea000700e620 ffffea00073f28a0 ffff8801dac00dc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c030cd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c030ce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c030ce80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c030cf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c030cf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================