================================================================== BUG: KASAN: slab-out-of-bounds in eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:283 Read of size 2 at addr ffff888029e8500b by task syz-executor.3/23686 CPU: 1 PID: 23686 Comm: syz-executor.3 Not tainted 5.12.0-rc4-next-20210326-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232 __kasan_report mm/kasan/report.c:399 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416 eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:283 dev_parse_header_protocol include/linux/netdevice.h:3264 [inline] virtio_net_hdr_to_skb.constprop.0+0x99d/0xcd0 include/linux/virtio_net.h:83 packet_snd net/packet/af_packet.c:2994 [inline] packet_sendmsg+0x2331/0x5280 net/packet/af_packet.c:3031 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 sock_write_iter+0x289/0x3c0 net/socket.c:1001 call_write_iter include/linux/fs.h:2106 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x796/0xa30 fs/read_write.c:605 ksys_write+0x1ee/0x250 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae 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:00007f86189d0188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000122 RSI: 0000000020000500 RDI: 0000000000000003 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd3100e16f R14: 00007f86189d0300 R15: 0000000000022000 Allocated by task 0: (stack is not available) Freed by task 4552: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:212 [inline] slab_free_hook mm/slub.c:1578 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1603 slab_free mm/slub.c:3163 [inline] kfree+0xe5/0x7f0 mm/slub.c:4230 skb_free_head net/core/skbuff.c:651 [inline] skb_release_data+0x622/0x750 net/core/skbuff.c:672 skb_release_all net/core/skbuff.c:726 [inline] __kfree_skb net/core/skbuff.c:740 [inline] consume_skb net/core/skbuff.c:896 [inline] consume_skb+0xc2/0x160 net/core/skbuff.c:890 nsim_dev_trap_report drivers/net/netdevsim/dev.c:586 [inline] nsim_dev_trap_report_work+0x86f/0xbd0 drivers/net/netdevsim/dev.c:611 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff888029e84000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 11 bytes to the right of 4096-byte region [ffff888029e84000, ffff888029e85000) The buggy address belongs to the page: page:ffffea0000a7a000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29e80 head:ffffea0000a7a000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010842140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888029e84f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029e84f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888029e85000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888029e85080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888029e85100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================