================================================================== BUG: KASAN: use-after-free in eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:282 Read of size 2 at addr ffff8880291e500b by task syz-executor.3/10731 CPU: 0 PID: 10731 Comm: syz-executor.3 Not tainted 5.12.0-rc6-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:282 dev_parse_header_protocol include/linux/netdevice.h:3179 [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+0x2325/0x52b0 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:1977 [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:00007f76d7a36188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 000000000000005a RSI: 0000000020000200 RDI: 0000000000000003 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 0000000000a9fb1f R14: 00007f76d7a36300 R15: 0000000000022000 Allocated by task 9720: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:427 [inline] __kasan_slab_alloc+0x75/0x90 mm/kasan/common.c:460 kasan_slab_alloc include/linux/kasan.h:223 [inline] slab_post_alloc_hook mm/slab.h:516 [inline] slab_alloc_node mm/slub.c:2907 [inline] kmem_cache_alloc_node+0x164/0x3b0 mm/slub.c:2943 __alloc_skb+0x20b/0x340 net/core/skbuff.c:412 alloc_skb include/linux/skbuff.h:1103 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:513 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:570 [inline] nsim_dev_trap_report_work+0x2ac/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 Freed by task 9720: 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+0xf5/0x130 mm/kasan/common.c:367 kasan_slab_free include/linux/kasan.h:199 [inline] slab_free_hook mm/slub.c:1562 [inline] slab_free_freelist_hook+0x92/0x210 mm/slub.c:1600 slab_free mm/slub.c:3161 [inline] kmem_cache_free+0x8a/0x740 mm/slub.c:3177 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:683 __kfree_skb net/core/skbuff.c:740 [inline] consume_skb net/core/skbuff.c:895 [inline] consume_skb+0xcf/0x160 net/core/skbuff.c:889 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 ffff8880291e5000 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 11 bytes inside of 232-byte region [ffff8880291e5000, ffff8880291e50e8) The buggy address belongs to the page: page:ffffea0000a47940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x291e5 flags: 0xfff00000000200(slab) raw: 00fff00000000200 ffffea00004853c0 0000000900000007 ffff8880110cadc0 raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880291e4f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880291e4f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880291e5000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880291e5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff8880291e5100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================