================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:344 [inline] BUG: KASAN: slab-out-of-bounds in tcp_v6_syn_recv_sock+0x1567/0x2330 net/ipv6/tcp_ipv6.c:1076 Write of size 152 at addr ffff8801c85d5ef0 by task syzkaller563069/3152 CPU: 0 PID: 3152 Comm: syzkaller563069 Not tainted 4.15.0-rc4-mm1+ #49 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:355 [inline] kasan_report+0x23b/0x360 mm/kasan/report.c:413 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:344 [inline] tcp_v6_syn_recv_sock+0x1567/0x2330 net/ipv6/tcp_ipv6.c:1076 tcp_get_cookie_sock+0x102/0x540 net/ipv4/syncookies.c:213 cookie_v4_check+0x1a87/0x2920 net/ipv4/syncookies.c:396 tcp_v4_cookie_check net/ipv4/tcp_ipv4.c:1439 [inline] tcp_v4_do_rcv+0x6e9/0x7d0 net/ipv4/tcp_ipv4.c:1476 tcp_v4_rcv+0x26c6/0x2e10 net/ipv4/tcp_ipv4.c:1735 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:281 [inline] ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0x881/0x19a0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:281 [inline] ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x1a3e/0x3450 net/core/dev.c:4497 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4562 process_backlog+0x203/0x740 net/core/dev.c:5242 napi_poll net/core/dev.c:5640 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5706 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1133 do_softirq.part.21+0x14d/0x190 kernel/softirq.c:329 do_softirq kernel/softirq.c:177 [inline] __local_bh_enable_ip+0x1ee/0x230 kernel/softirq.c:182 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:726 [inline] ip_finish_output2+0x8a7/0x1460 net/ipv4/ip_output.c:231 ip_finish_output+0x85e/0xd10 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:270 [inline] ip_output+0x1cc/0x860 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:443 [inline] ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124 ip_queue_xmit+0x8c0/0x18e0 net/ipv4/ip_output.c:504 tcp_transmit_skb+0x1b12/0x38b0 net/ipv4/tcp_output.c:1176 tcp_send_ack.part.41+0x389/0x610 net/ipv4/tcp_output.c:3614 tcp_send_ack+0x49/0x60 net/ipv4/tcp_output.c:3584 tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:5700 [inline] tcp_rcv_state_process+0x3d0f/0x4830 net/ipv4/tcp_input.c:5835 tcp_v4_do_rcv+0x55c/0x7d0 net/ipv4/tcp_ipv4.c:1490 sk_backlog_rcv include/net/sock.h:907 [inline] __release_sock+0x124/0x360 net/core/sock.c:2274 release_sock+0xa4/0x2a0 net/core/sock.c:2789 tcp_sendmsg+0x3a/0x50 net/ipv4/tcp.c:1460 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:628 [inline] sock_sendmsg+0xca/0x110 net/socket.c:638 SYSC_sendto+0x361/0x5c0 net/socket.c:1719 SyS_sendto+0x40/0x50 net/socket.c:1687 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x43feb9 RSP: 002b:00007ffe9efaa3d8 EFLAGS: 00000217 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 000000000043feb9 RDX: 0000000000000000 RSI: 000000002087a000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000200b0000 R09: 0000000000000010 R10: 0000000020008045 R11: 0000000000000217 R12: 0000000000401820 R13: 00000000004018b0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3152: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3541 sk_prot_alloc+0x65/0x2a0 net/core/sock.c:1465 sk_clone_lock+0x152/0x1630 net/core/sock.c:1657 inet_csk_clone_lock+0x91/0x4c0 net/ipv4/inet_connection_sock.c:781 tcp_create_openreq_child+0x9b/0x1b70 net/ipv4/tcp_minisocks.c:450 tcp_v4_syn_recv_sock+0x119/0x1260 net/ipv4/tcp_ipv4.c:1350 tcp_v6_syn_recv_sock+0x14c9/0x2330 net/ipv6/tcp_ipv6.c:1063 tcp_get_cookie_sock+0x102/0x540 net/ipv4/syncookies.c:213 cookie_v4_check+0x1a87/0x2920 net/ipv4/syncookies.c:396 tcp_v4_cookie_check net/ipv4/tcp_ipv4.c:1439 [inline] tcp_v4_do_rcv+0x6e9/0x7d0 net/ipv4/tcp_ipv4.c:1476 tcp_v4_rcv+0x26c6/0x2e10 net/ipv4/tcp_ipv4.c:1735 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:281 [inline] ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0x881/0x19a0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:281 [inline] ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x1a3e/0x3450 net/core/dev.c:4497 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4562 process_backlog+0x203/0x740 net/core/dev.c:5242 napi_poll net/core/dev.c:5640 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5706 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8801c85d5500 which belongs to the cache TCP of size 2544 The buggy address is located 0 bytes to the right of 2544-byte region [ffff8801c85d5500, ffff8801c85d5ef0) The buggy address belongs to the page: page:ffffea0007217500 count:1 mapcount:0 mapping:ffff8801c85d4000 index:0xffff8801c85d5ffd compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801c85d4000 ffff8801c85d5ffd 0000000100000003 raw: ffffea00072ec8a0 ffff8801d6d2ed48 ffff8801d7941c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c85d5d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801c85d5e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801c85d5e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ^ ffff8801c85d5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801c85d5f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================