================================================================== BUG: KASAN: use-after-free in eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:283 Read of size 2 at addr ffff888084f0440b by task syz-executor.4/3668 CPU: 1 PID: 3668 Comm: syz-executor.4 Not tainted 5.12.0-rc4-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+0x233c/0x5300 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:00007fb60b957188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000020 RSI: 0000000020000240 RDI: 0000000000000003 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff4c7fdadf R14: 00007fb60b957300 R15: 0000000000022000 Allocated by task 8444: 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_kmalloc mm/kasan/common.c:506 [inline] ____kasan_kmalloc mm/kasan/common.c:465 [inline] __kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515 kmalloc_node include/linux/slab.h:577 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:587 kvmalloc include/linux/mm.h:785 [inline] kvmalloc_array include/linux/mm.h:803 [inline] alloc_fdtable+0xee/0x2a0 fs/file.c:120 dup_fd+0x726/0xc90 fs/file.c:325 copy_files kernel/fork.c:1476 [inline] copy_process+0x205e/0x71a0 kernel/fork.c:2100 kernel_clone+0xe7/0xab0 kernel/fork.c:2505 __do_sys_clone+0xc8/0x110 kernel/fork.c:2622 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 3586: 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] kfree+0xe5/0x7f0 mm/slub.c:4213 kvfree+0x42/0x50 mm/util.c:616 __free_fdtable fs/file.c:36 [inline] put_files_struct fs/file.c:422 [inline] put_files_struct+0x270/0x350 fs/file.c:415 exit_files+0x7e/0xa0 fs/file.c:435 do_exit+0xbc2/0x2a60 kernel/exit.c:820 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x42c/0x2100 kernel/signal.c:2777 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:345 kvfree_call_rcu+0x10e/0x7d0 kernel/rcu/tree.c:3577 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1652 unregister_sysctl_table fs/proc/proc_sysctl.c:1690 [inline] unregister_sysctl_table+0xc2/0x190 fs/proc/proc_sysctl.c:1665 __devinet_sysctl_unregister net/ipv4/devinet.c:2594 [inline] devinet_exit_net+0xe4/0x280 net/ipv4/devinet.c:2733 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:175 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:595 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 Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:345 __call_rcu kernel/rcu/tree.c:3039 [inline] call_rcu+0xb1/0x740 kernel/rcu/tree.c:3114 in6_dev_finish_destroy+0x157/0x1e0 net/ipv6/addrconf_core.c:271 in6_dev_put include/net/addrconf.h:379 [inline] addrconf_ifdown.isra.0+0x12ca/0x15b0 net/ipv6/addrconf.c:3852 addrconf_notify+0x55c/0x23e0 net/ipv6/addrconf.c:3631 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2121 call_netdevice_notifiers_extack net/core/dev.c:2133 [inline] call_netdevice_notifiers net/core/dev.c:2147 [inline] unregister_netdevice_many+0x942/0x1780 net/core/dev.c:11000 ip_tunnel_delete_nets+0x3eb/0x5b0 net/ipv4/ip_tunnel.c:1113 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:178 setup_net+0x639/0xa30 net/core/net_namespace.c:356 copy_net_ns+0x31e/0x760 net/core/net_namespace.c:474 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x8e0 kernel/fork.c:2998 __do_sys_unshare kernel/fork.c:3066 [inline] __se_sys_unshare kernel/fork.c:3064 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3064 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff888084f04000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1035 bytes inside of 2048-byte region [ffff888084f04000, ffff888084f04800) The buggy address belongs to the page: page:ffffea000213c000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x84f00 head:ffffea000213c000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head) raw: 00fff00000010200 0000000000000000 0000000600000001 ffff888010842000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888084f04300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888084f04380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888084f04400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888084f04480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888084f04500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================