================================================================== BUG: KASAN: use-after-free in eth_header_parse_protocol+0xad/0xd0 net/ethernet/eth.c:282 Read of size 2 at addr ffff8881f126f80b by task syz-executor.4/1335 CPU: 1 PID: 1335 Comm: syz-executor.4 Not tainted 5.4.111-syzkaller-00141-gce6a5172613f #0 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+0x1d8/0x24e lib/dump_stack.c:118 print_address_description+0x9b/0x650 mm/kasan/report.c:384 __kasan_report+0x182/0x260 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:641 eth_header_parse_protocol+0xad/0xd0 net/ethernet/eth.c:282 dev_parse_header_protocol include/linux/netdevice.h:3016 [inline] virtio_net_hdr_to_skb+0x6de/0xd70 include/linux/virtio_net.h:83 packet_snd net/packet/af_packet.c:2976 [inline] packet_sendmsg+0x483a/0x6780 net/packet/af_packet.c:3013 sock_sendmsg_nosec net/socket.c:638 [inline] sock_sendmsg net/socket.c:658 [inline] sock_write_iter+0x330/0x450 net/socket.c:990 call_write_iter include/linux/fs.h:1971 [inline] new_sync_write fs/read_write.c:483 [inline] __vfs_write+0x5ec/0x780 fs/read_write.c:496 vfs_write+0x212/0x4e0 fs/read_write.c:558 ksys_write+0x186/0x2b0 fs/read_write.c:611 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x466459 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2c96140188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000018 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe9de68dbf R14: 00007f2c96140300 R15: 0000000000022000 Allocated by task 142: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x137/0x1e0 mm/kasan/common.c:517 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2821 [inline] slab_alloc mm/slub.c:2829 [inline] kmem_cache_alloc+0x115/0x290 mm/slub.c:2834 vm_area_dup kernel/fork.c:358 [inline] dup_mmap+0x4bf/0xbd0 kernel/fork.c:545 dup_mm+0x8c/0x300 kernel/fork.c:1367 copy_mm kernel/fork.c:1423 [inline] copy_process+0x1f3d/0x5630 kernel/fork.c:2040 _do_fork+0x18f/0x900 kernel/fork.c:2391 __do_sys_clone kernel/fork.c:2549 [inline] __se_sys_clone kernel/fork.c:2530 [inline] __x64_sys_clone+0x25b/0x2c0 kernel/fork.c:2530 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 907: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:333 [inline] __kasan_slab_free+0x18a/0x240 mm/kasan/common.c:475 slab_free_hook mm/slub.c:1454 [inline] slab_free_freelist_hook+0x7b/0x150 mm/slub.c:1492 slab_free mm/slub.c:3072 [inline] kmem_cache_free+0xb8/0x5f0 mm/slub.c:3088 remove_vma mm/mmap.c:181 [inline] exit_mmap+0x43d/0x540 mm/mmap.c:3185 __mmput+0x34/0x240 kernel/fork.c:1089 exit_mm kernel/exit.c:489 [inline] do_exit+0xc19/0x2bf0 kernel/exit.c:799 do_group_exit+0x15c/0x2c0 kernel/exit.c:910 __do_sys_exit_group+0x13/0x20 kernel/exit.c:921 __ia32_sys_exit_group+0x0/0x40 kernel/exit.c:919 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:919 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881f126f7e0 which belongs to the cache vm_area_struct of size 224 The buggy address is located 43 bytes inside of 224-byte region [ffff8881f126f7e0, ffff8881f126f8c0) The buggy address belongs to the page: page:ffffea0007c49bc0 refcount:1 mapcount:0 mapping:ffff8881f5cf8780 index:0x0 flags: 0x8000000000000200(slab) raw: 8000000000000200 dead000000000100 dead000000000122 ffff8881f5cf8780 raw: 0000000000000000 00000000000e000e 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881f126f700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881f126f780: fb fb fb fb fc fc fc fc fc fc fc fc fb fb fb fb >ffff8881f126f800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881f126f880: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881f126f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================