RAX: ffffffffffffffda RBX: 00007f1261a87c90 RCX: 0000000000458da9
RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1261a886d4
R13: 00000000004c60ad R14: 00000000004daaf0 R15: 0000000000000006
dccp_parse_options: DCCP(000000008696af2f): Option 32 (len=7) error=9
==================================================================
BUG: KASAN: use-after-free in ccid2_hc_tx_packet_recv+0x21ca/0x223b net/dccp/ccids/ccid2.c:600
Read of size 1 at addr ffff88806a313a14 by task syz-executor.3/22550

CPU: 0 PID: 22550 Comm: syz-executor.3 Not tainted 5.1.0+ #5
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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188
 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 kasan_report+0x12/0x20 mm/kasan/common.c:614
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:129
 ccid2_hc_tx_packet_recv+0x21ca/0x223b net/dccp/ccids/ccid2.c:600
 ccid_hc_tx_packet_recv net/dccp/ccid.h:192 [inline]
 dccp_deliver_input_to_ccids+0x202/0x280 net/dccp/input.c:186
 dccp_rcv_established net/dccp/input.c:378 [inline]
 dccp_rcv_established+0x83/0xb0 net/dccp/input.c:368
 dccp_v4_do_rcv+0x139/0x190 net/dccp/ipv4.c:659
 sk_backlog_rcv include/net/sock.h:950 [inline]
 __release_sock+0x12e/0x3a0 net/core/sock.c:2418
 release_sock+0x59/0x1c0 net/core/sock.c:2934
 dccp_sendmsg+0x683/0xd00 net/dccp/proto.c:818
 inet_sendmsg+0x147/0x5e0 net/ipv4/af_inet.c:802
 sock_sendmsg_nosec net/socket.c:660 [inline]
 sock_sendmsg+0xf2/0x170 net/socket.c:671
 ___sys_sendmsg+0x3e2/0x960 net/socket.c:2292
 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2387
 __do_sys_sendmmsg net/socket.c:2416 [inline]
 __se_sys_sendmmsg net/socket.c:2413 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2413
 do_syscall_64+0x103/0x670 arch/x86/entry/common.c:298
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458da9
Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1261a87c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f1261a87c90 RCX: 0000000000458da9
RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1261a886d4
R13: 00000000004c60ad R14: 00000000004daaf0 R15: 0000000000000006

Allocated by task 22550:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_kmalloc mm/kasan/common.c:489 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503
 __do_kmalloc_node mm/slab.c:3651 [inline]
 __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3665
 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:142
 __alloc_skb+0x10b/0x5e0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1058 [inline]
 dccp_send_ack+0xd6/0x360 net/dccp/output.c:580
 ccid2_hc_rx_packet_recv+0x139/0x1b0 net/dccp/ccids/ccid2.c:779
 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline]
 dccp_deliver_input_to_ccids+0xee/0x280 net/dccp/input.c:180
 dccp_rcv_established net/dccp/input.c:378 [inline]
 dccp_rcv_established+0x83/0xb0 net/dccp/input.c:368
 dccp_v4_do_rcv+0x139/0x190 net/dccp/ipv4.c:659
 sk_backlog_rcv include/net/sock.h:950 [inline]
 __sk_receive_skb+0x33a/0xbe0 net/core/sock.c:528
 dccp_v4_rcv+0xeaa/0x1bf1 net/dccp/ipv4.c:880
 ip_protocol_deliver_rcu+0x74c/0x940 net/ipv4/ip_input.c:211
 ip_local_deliver_finish+0x23b/0x390 net/ipv4/ip_input.c:238
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x1e9/0x520 net/ipv4/ip_input.c:259
 dst_input include/net/dst.h:439 [inline]
 ip_rcv_finish+0x1e1/0x300 net/ipv4/ip_input.c:420
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:530
 __netif_receive_skb_one_core+0x18d/0x1f0 net/core/dev.c:4990
 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5104
 process_backlog+0x206/0x750 net/core/dev.c:5944
 napi_poll net/core/dev.c:6367 [inline]
 net_rx_action+0x4fa/0x1070 net/core/dev.c:6433
 __do_softirq+0x266/0x95a kernel/softirq.c:293

Freed by task 22550:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
 __cache_free mm/slab.c:3463 [inline]
 kfree+0xcf/0x230 mm/slab.c:3786
 skb_free_head+0x93/0xb0 net/core/skbuff.c:592
 skb_release_data+0x576/0x7a0 net/core/skbuff.c:612
 skb_release_all+0x4d/0x60 net/core/skbuff.c:666
 __kfree_skb net/core/skbuff.c:680 [inline]
 kfree_skb net/core/skbuff.c:698 [inline]
 kfree_skb+0xe8/0x390 net/core/skbuff.c:692
 dccp_v4_do_rcv net/dccp/ipv4.c:694 [inline]
 dccp_v4_do_rcv+0x160/0x190 net/dccp/ipv4.c:654
 sk_backlog_rcv include/net/sock.h:950 [inline]
 __release_sock+0x12e/0x3a0 net/core/sock.c:2418
 release_sock+0x59/0x1c0 net/core/sock.c:2934
 dccp_sendmsg+0x683/0xd00 net/dccp/proto.c:818
 inet_sendmsg+0x147/0x5e0 net/ipv4/af_inet.c:802
 sock_sendmsg_nosec net/socket.c:660 [inline]
 sock_sendmsg+0xf2/0x170 net/socket.c:671
 ___sys_sendmsg+0x3e2/0x960 net/socket.c:2292
 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2387
 __do_sys_sendmmsg net/socket.c:2416 [inline]
 __se_sys_sendmmsg net/socket.c:2413 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2413
 do_syscall_64+0x103/0x670 arch/x86/entry/common.c:298
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88806a313580
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1172 bytes inside of
 2048-byte region [ffff88806a313580, ffff88806a313d80)
The buggy address belongs to the page:
page:ffffea0001a8c480 count:1 mapcount:0 mapping:ffff8880aa400c40 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0002524f08 ffffea000237a608 ffff8880aa400c40
raw: 0000000000000000 ffff88806a312480 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806a313900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806a313980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88806a313a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88806a313a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806a313b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================