R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 dccp_parse_options: DCCP(000000007d56a000): Option 32 (len=7) error=9 ================================================================== dccp_check_seqno: Step 6 failed for RESET packet, (LSWL(279336972291068) <= P.seqno(279336972291066) <= S.SWH(279336972291142)) and (P.ackno exists or LAWL(234137106534459) <= P.ackno(234137106534459) <= S.AWH(234137106534460), sending SYNC... BUG: KASAN: use-after-free in ccid2_hc_tx_packet_recv+0x234a/0x2440 net/dccp/ccids/ccid2.c:598 Read of size 1 at addr ffff8801bb7a4a82 by task syz-executor1/1660 CPU: 1 PID: 1660 Comm: syz-executor1 Not tainted 4.16.0+ #285 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+0x194/0x24d lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report+0x23c/0x360 mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 ccid2_hc_tx_packet_recv+0x234a/0x2440 net/dccp/ccids/ccid2.c:598 ccid_hc_tx_packet_recv net/dccp/ccid.h:192 [inline] dccp_deliver_input_to_ccids+0x1d0/0x250 net/dccp/input.c:186 dccp_rcv_established+0x88/0xb0 net/dccp/input.c:378 dccp_v4_do_rcv+0x135/0x160 net/dccp/ipv4.c:653 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x124/0x360 net/core/sock.c:2271 release_sock+0xa4/0x2a0 net/core/sock.c:2786 dccp_sendmsg+0x528/0xe60 net/dccp/proto.c:820 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 ___sys_sendmsg+0x320/0x8b0 net/socket.c:2046 __sys_sendmmsg+0x31b/0x620 net/socket.c:2129 C_SYSC_sendmmsg net/compat.c:745 [inline] compat_SyS_sendmmsg+0x32/0x40 net/compat.c:742 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f6dc99 RSP: 002b:00000000f5f690ac EFLAGS: 00000282 ORIG_RAX: 0000000000000159 RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 000000002000b880 RDX: 0000000000000122 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 1660: 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:552 __do_kmalloc_node mm/slab.c:3670 [inline] __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3684 __kmalloc_reserve.isra.39+0x41/0xd0 net/core/skbuff.c:137 __alloc_skb+0x13b/0x780 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:983 [inline] dccp_send_ack+0xb6/0x350 net/dccp/output.c:580 ccid2_hc_rx_packet_recv+0x10d/0x180 net/dccp/ccids/ccid2.c:766 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline] dccp_deliver_input_to_ccids+0xd9/0x250 net/dccp/input.c:180 dccp_rcv_established+0x88/0xb0 net/dccp/input.c:378 dccp_v4_do_rcv+0x135/0x160 net/dccp/ipv4.c:653 sk_backlog_rcv include/net/sock.h:908 [inline] __sk_receive_skb+0x33e/0xc10 net/core/sock.c:513 dccp_v4_rcv+0xf5f/0x1c80 net/dccp/ipv4.c:874 ip_local_deliver_finish+0x2f1/0xc50 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0xa36/0x2040 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0xb76/0x1820 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x1a41/0x3460 net/core/dev.c:4562 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4627 process_backlog+0x203/0x740 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5771 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 Freed by task 1660: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527 __cache_free mm/slab.c:3486 [inline] kfree+0xd9/0x260 mm/slab.c:3801 skb_free_head+0x74/0xb0 net/core/skbuff.c:550 skb_release_data+0x58c/0x790 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] kfree_skb+0x15d/0x4c0 net/core/skbuff.c:659 dccp_v4_do_rcv+0x10d/0x160 net/dccp/ipv4.c:688 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x124/0x360 net/core/sock.c:2271 release_sock+0xa4/0x2a0 net/core/sock.c:2786 dccp_sendmsg+0x528/0xe60 net/dccp/proto.c:820 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 ___sys_sendmsg+0x320/0x8b0 net/socket.c:2046 __sys_sendmmsg+0x31b/0x620 net/socket.c:2129 C_SYSC_sendmmsg net/compat.c:745 [inline] compat_SyS_sendmmsg+0x32/0x40 net/compat.c:742 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 The buggy address belongs to the object at ffff8801bb7a4600 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 1154 bytes inside of 2048-byte region [ffff8801bb7a4600, ffff8801bb7a4e00) The buggy address belongs to the page: page:ffffea0006ede900 count:1 mapcount:0 mapping:ffff8801bb7a4600 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801bb7a4600 0000000000000000 0000000100000003 raw: ffffea0006bcbd20 ffffea0006f5b1a0 ffff8801dac00c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801bb7a4980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801bb7a4a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801bb7a4a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801bb7a4b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801bb7a4b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================