================================================================== BUG: KASAN: use-after-free in __xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2019 [inline] BUG: KASAN: use-after-free in xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2053 [inline] BUG: KASAN: use-after-free in xfrm_policy_lookup_bytype+0xe52/0xe70 net/xfrm/xfrm_policy.c:2113 Read of size 4 at addr ffff888086947734 by task syz-executor4/24488 CPU: 1 PID: 24488 Comm: syz-executor4 Not tainted 4.20.0+ #252 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+0x1d3/0x2c6 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 __xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2019 [inline] xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2053 [inline] xfrm_policy_lookup_bytype+0xe52/0xe70 net/xfrm/xfrm_policy.c:2113 xfrm_policy_lookup+0x7e/0x80 net/xfrm/xfrm_policy.c:2145 __xfrm_policy_check+0x14f0/0x2c40 net/xfrm/xfrm_policy.c:3354 __xfrm_policy_check2 include/net/xfrm.h:1166 [inline] xfrm_policy_check include/net/xfrm.h:1175 [inline] xfrm6_policy_check include/net/xfrm.h:1185 [inline] tcp_v6_rcv+0x30c4/0x38b0 net/ipv6/tcp_ipv6.c:1534 ip6_protocol_deliver_rcu+0x372/0x1940 net/ipv6/ip6_input.c:394 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:443 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x115/0x640 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5083 process_backlog+0x217/0x760 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x7c5/0x1950 net/core/dev.c:6412 __do_softirq+0x30c/0xb2e kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.13+0x126/0x160 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x21d/0x260 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip6_finish_output2+0xcef/0x2930 net/ipv6/ip6_output.c:121 ip6_finish_output+0x583/0xc50 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip6_xmit+0xf0d/0x24c0 net/ipv6/ip6_output.c:275 inet6_csk_xmit+0x378/0x630 net/ipv6/inet6_connection_sock.c:139 __tcp_transmit_skb+0x1b9f/0x3b90 net/ipv4/tcp_output.c:1160 tcp_transmit_skb net/ipv4/tcp_output.c:1176 [inline] tcp_send_syn_data net/ipv4/tcp_output.c:3495 [inline] tcp_connect+0x2271/0x4690 net/ipv4/tcp_output.c:3534 tcp_v6_connect+0x1c1e/0x29c0 net/ipv6/tcp_ipv6.c:321 __inet_stream_connect+0x992/0x1150 net/ipv4/af_inet.c:655 tcp_sendmsg_fastopen net/ipv4/tcp.c:1161 [inline] tcp_sendmsg_locked+0x2890/0x3f30 net/ipv4/tcp.c:1208 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1443 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 __sys_sendto+0x3d7/0x670 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto net/socket.c:1796 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4579b9 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f602ab01c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004579b9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 000000000073bf00 R08: 0000000020b63fe4 R09: 000000000000001c R10: 0000080020000001 R11: 0000000000000246 R12: 00007f602ab026d4 R13: 00000000004c4e37 R14: 00000000004d8640 R15: 00000000ffffffff Allocated by task 23146: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3684 [inline] __kmalloc_node_track_caller+0x50/0x70 mm/slab.c:3698 __kmalloc_reserve.isra.40+0x41/0xe0 net/core/skbuff.c:140 __alloc_skb+0x155/0x760 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1011 [inline] alloc_skb_with_frags+0x133/0x7c0 net/core/skbuff.c:5288 sock_alloc_send_pskb+0x865/0xab0 net/core/sock.c:2091 sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2108 __ip6_append_data.isra.50+0x253c/0x3f50 net/ipv6/ip6_output.c:1443 ip6_make_skb+0x380/0x5e0 net/ipv6/ip6_output.c:1806 udpv6_sendmsg+0x2d37/0x36a0 net/ipv6/udp.c:1460 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x51d/0x930 net/socket.c:2116 __sys_sendmmsg+0x246/0x6d0 net/socket.c:2211 __do_sys_sendmmsg net/socket.c:2240 [inline] __se_sys_sendmmsg net/socket.c:2237 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2237 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 23146: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 skb_free_head+0x93/0xb0 net/core/skbuff.c:553 skb_release_data+0x706/0x990 net/core/skbuff.c:573 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] kfree_skb+0x1bb/0x580 net/core/skbuff.c:659 ip6_finish_output2+0x17d6/0x2930 net/ipv6/ip6_output.c:101 ip6_finish_output+0x583/0xc50 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0xc5/0x1b0 net/ipv6/output_core.c:176 ip6_send_skb+0xbc/0x340 net/ipv6/ip6_output.c:1727 udp_v6_send_skb.isra.32+0x831/0x14a0 net/ipv6/udp.c:1169 udpv6_sendmsg+0x2d86/0x36a0 net/ipv6/udp.c:1466 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x51d/0x930 net/socket.c:2116 __sys_sendmmsg+0x246/0x6d0 net/socket.c:2211 __do_sys_sendmmsg net/socket.c:2240 [inline] __se_sys_sendmmsg net/socket.c:2237 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2237 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888086947680 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 180 bytes inside of 1024-byte region [ffff888086947680, ffff888086947a80) The buggy address belongs to the page: page:ffffea00021a5180 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0xffff888086946900 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002381708 ffffea000249a908 ffff88812c3f0ac0 raw: ffff888086946900 ffff888086946000 0000000100000002 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888086947600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888086947680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888086947700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888086947780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888086947800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================