================================================================== BUG: KASAN: use-after-free in nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 Read of size 1 at addr ffff8801cfc0f2be by task syz-executor0/12399 CPU: 1 PID: 12399 Comm: syz-executor0 Not tainted 4.17.0-rc7+ #76 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+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 nfnl_acct_new+0x574/0xc50 net/netfilter/nfnetlink_acct.c:118 nfnetlink_rcv_msg+0xdb5/0xff0 net/netfilter/nfnetlink.c:212 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448 nfnetlink_rcv+0x1fe/0x1ba0 net/netfilter/nfnetlink.c:513 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x9f0/0xfa0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 ___sys_sendmsg+0x805/0x940 net/socket.c:2117 __sys_sendmsg+0x115/0x270 net/socket.c:2155 __do_sys_sendmsg net/socket.c:2164 [inline] __se_sys_sendmsg net/socket.c:2162 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2162 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007f792a730c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f792a7316d4 RCX: 0000000000455a09 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000015 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000005cf R14: 00000000006fdc08 R15: 0000000000000000 Allocated by task 10934: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3696 __kmalloc_reserve.isra.38+0x3a/0xe0 net/core/skbuff.c:137 __alloc_skb+0x14d/0x780 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:987 [inline] dccp_send_ack+0xd2/0x340 net/dccp/output.c:580 ccid2_hc_rx_packet_recv+0x139/0x1b0 net/dccp/ccids/ccid2.c:776 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline] dccp_deliver_input_to_ccids+0xf0/0x280 net/dccp/input.c:180 dccp_rcv_established+0x87/0xb0 net/dccp/input.c:378 dccp_v4_do_rcv+0x153/0x180 net/dccp/ipv4.c:654 sk_backlog_rcv include/net/sock.h:909 [inline] __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513 dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875 ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492 __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657 process_backlog+0x219/0x760 net/core/dev.c:5337 napi_poll net/core/dev.c:5735 [inline] net_rx_action+0x7b7/0x1930 net/core/dev.c:5801 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 Freed by task 10934: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x690/0x860 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb+0x15/0x20 net/core/skbuff.c:641 __dccp_rcv_established.isra.6+0x19e/0x3a0 net/dccp/input.c:364 dccp_rcv_established+0x92/0xb0 net/dccp/input.c:380 dccp_v4_do_rcv+0x153/0x180 net/dccp/ipv4.c:654 sk_backlog_rcv include/net/sock.h:909 [inline] __release_sock+0x12f/0x3a0 net/core/sock.c:2335 release_sock+0xa4/0x2b0 net/core/sock.c:2850 dccp_sendmsg+0x771/0x1020 net/dccp/proto.c:818 inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 ___sys_sendmsg+0x525/0x940 net/socket.c:2117 __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212 __do_sys_sendmmsg net/socket.c:2241 [inline] __se_sys_sendmmsg net/socket.c:2238 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801cfc0f280 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 62 bytes inside of 2048-byte region [ffff8801cfc0f280, ffff8801cfc0fa80) The buggy address belongs to the page: page:ffffea00073f0380 count:1 mapcount:0 mapping:ffff8801cfc0e180 index:0xffff8801cfc0f280 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801cfc0e180 ffff8801cfc0f280 0000000100000002 raw: ffffea0006ba87a0 ffffea00073fa8a0 ffff8801da800c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cfc0f180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801cfc0f200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801cfc0f280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801cfc0f300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cfc0f380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================