==================================================================
BUG: KASAN: use-after-free in ccid_hc_tx_delete+0xde/0x100 net/dccp/ccid.c:188
Read of size 8 at addr ffff888094f35a00 by task syz-executor.5/10701

CPU: 0 PID: 10701 Comm: syz-executor.5 Not tainted 5.0.0-rc5+ #65
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __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:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 ccid_hc_tx_delete+0xde/0x100 net/dccp/ccid.c:188
 dccp_sk_destruct+0x3f/0x90 net/dccp/proto.c:181
 __sk_destruct+0x55/0x6d0 net/core/sock.c:1569
 __rcu_reclaim kernel/rcu/rcu.h:240 [inline]
 rcu_do_batch kernel/rcu/tree.c:2452 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline]
 rcu_process_callbacks+0x928/0x1390 kernel/rcu/tree.c:2754
 __do_softirq+0x266/0x95a kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x14a/0x570 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:unwind_next_frame.part.0+0x26/0x9a0 arch/x86/kernel/unwind_frame.c:282
Code: 12 00 66 90 55 4c 8d 4f 50 48 b8 00 00 00 00 00 fc ff df 48 89 e5 41 57 41 56 41 55 41 54 4c 8d a5 78 ff ff ff 49 c1 ec 03 53 <48> 89 fb 49 8d 14 04 48 81 ec 88 00 00 00 48 c7 85 78 ff ff ff b3
RSP: 0018:ffff88809782f740 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff88809782f830 RCX: 0000000000000008
RDX: 0000000000000001 RSI: ffffffff866fc17b RDI: ffff88809782f790
RBP: ffff88809782f768 R08: 0000000000000001 R09: ffff88809782f7e0
R10: ffff88809782f7b8 R11: ffff88809782f7c8 R12: 1ffff11012f05edc
R13: 0000000000000000 R14: ffff8880a46800c0 R15: ffff88812c3f01c0
 unwind_next_frame+0x3b/0x50 arch/x86/kernel/unwind_frame.c:287
 __save_stack_trace+0x7a/0xf0 arch/x86/kernel/stacktrace.c:44
 save_stack_trace+0x1a/0x20 arch/x86/kernel/stacktrace.c:60
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
 __do_kmalloc mm/slab.c:3711 [inline]
 __kmalloc_track_caller+0x158/0x740 mm/slab.c:3726
 kmemdup+0x27/0x60 mm/util.c:111
 kmemdup include/linux/string.h:425 [inline]
 dccp_feat_clone_sp_val.part.0+0x5d/0xe0 net/dccp/feat.c:374
 dccp_feat_clone_sp_val net/dccp/feat.c:373 [inline]
 __feat_register_sp+0x1df/0x330 net/dccp/feat.c:738
 dccp_feat_init+0x16b/0x310 net/dccp/feat.c:1464
 dccp_init_sock+0x320/0x3f0 net/dccp/proto.c:208
 dccp_v6_init_sock+0x20/0xa0 net/dccp/ipv6.c:1008
 inet6_create net/ipv6/af_inet6.c:256 [inline]
 inet6_create+0x9cd/0xf90 net/ipv6/af_inet6.c:110
 __sock_create+0x3e6/0x750 net/socket.c:1275
 sock_create net/socket.c:1315 [inline]
 __sys_socket+0x103/0x220 net/socket.c:1345
 __do_sys_socket net/socket.c:1354 [inline]
 __se_sys_socket net/socket.c:1352 [inline]
 __x64_sys_socket+0x73/0xb0 net/socket.c:1352
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457e39
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:00007feb3fe92c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e39
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 000000000000000a
RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007feb3fe936d4
R13: 00000000004c6188 R14: 00000000004db320 R15: 00000000ffffffff

Allocated by task 10683:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc mm/kasan/common.c:504 [inline]
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:411
 kmem_cache_alloc+0x12d/0x710 mm/slab.c:3543
 ccid_new+0x256/0x3f0 net/dccp/ccid.c:151
 dccp_hdlr_ccid+0x27/0x150 net/dccp/feat.c:44
 __dccp_feat_activate+0x17a/0x270 net/dccp/feat.c:344
 dccp_feat_activate_values+0x33a/0x766 net/dccp/feat.c:1538
 dccp_rcv_request_sent_state_process net/dccp/input.c:472 [inline]
 dccp_rcv_state_process+0x116f/0x1931 net/dccp/input.c:680
 dccp_v6_do_rcv+0x269/0xbf0 net/dccp/ipv6.c:641
 sk_backlog_rcv include/net/sock.h:936 [inline]
 __release_sock+0x12e/0x3a0 net/core/sock.c:2284
 release_sock+0x59/0x1c0 net/core/sock.c:2800
 inet_wait_for_connect net/ipv4/af_inet.c:588 [inline]
 __inet_stream_connect+0x59f/0xea0 net/ipv4/af_inet.c:680
 inet_stream_connect+0x58/0xa0 net/ipv4/af_inet.c:719
 __sys_connect+0x266/0x330 net/socket.c:1662
 __do_sys_connect net/socket.c:1673 [inline]
 __se_sys_connect net/socket.c:1670 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1670
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 10691:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466
 __cache_free mm/slab.c:3487 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3749
 ccid_hc_tx_delete+0xc1/0x100 net/dccp/ccid.c:190
 dccp_hdlr_ccid+0x7d/0x150 net/dccp/feat.c:53
 __dccp_feat_activate+0x17a/0x270 net/dccp/feat.c:344
 dccp_feat_activate_values+0x33a/0x766 net/dccp/feat.c:1538
 dccp_create_openreq_child+0x40c/0x570 net/dccp/minisocks.c:127
 dccp_v6_request_recv_sock+0x214/0x1da0 net/dccp/ipv6.c:469
 dccp_check_req+0x35c/0x6f0 net/dccp/minisocks.c:196
 dccp_v6_rcv+0x6d7/0x191e net/dccp/ipv6.c:747
 ip6_protocol_deliver_rcu+0x303/0x16c0 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]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:443
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x1e7/0x320 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 process_backlog+0x206/0x750 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x4fa/0x1070 net/core/dev.c:6412
 __do_softirq+0x266/0x95a kernel/softirq.c:292

The buggy address belongs to the object at ffff888094f35a00
 which belongs to the cache ccid2_hc_tx_sock of size 1240
The buggy address is located 0 bytes inside of
 1240-byte region [ffff888094f35a00, ffff888094f35ed8)
The buggy address belongs to the page:
page:ffffea000253cd00 count:1 mapcount:0 mapping:ffff88821669d180 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00024ed088 ffffea00029e4408 ffff88821669d180
raw: 0000000000000000 ffff888094f34400 0000000100000005 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888094f35900: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff888094f35980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888094f35a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888094f35a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888094f35b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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