==================================================================
BUG: KASAN: use-after-free in ccid_hc_tx_delete+0xde/0x100 net/dccp/ccid.c:188
Read of size 8 at addr ffff88806413d640 by task syz-executor.0/8032

CPU: 0 PID: 8032 Comm: syz-executor.0 Not tainted 5.0.0+ #22
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:132
 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:1699
 __rcu_reclaim kernel/rcu/rcu.h:227 [inline]
 rcu_do_batch kernel/rcu/tree.c:2475 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2788 [inline]
 rcu_core+0x928/0x1390 kernel/rcu/tree.c:2769
 __do_softirq+0x266/0x95a kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:414
 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:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:66
Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01
RSP: 0018:ffff888065a07468 EFLAGS: 00010206 ORIG_RAX: ffffffffffffff13
RAX: dffffc00000000ff RBX: 0000000000000200 RCX: 0000000000006ac0
RDX: 0000000000040000 RSI: 00000000000000ff RDI: ffffed100c9b9540
RBP: ffff888065a07470 R08: 1ffff1100c980000 R09: ffffed100c980000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea0001930000
R13: 0000000000064c00 R14: ffff888064c00000 R15: 0000000000064c00
 free_pages_prepare mm/page_alloc.c:1135 [inline]
 __free_pages_ok+0x275/0xda0 mm/page_alloc.c:1353
 free_compound_page+0x6a/0x90 mm/page_alloc.c:611
 free_transhuge_page+0x230/0x310 mm/huge_memory.c:2760
 __put_compound_page+0x96/0xe0 mm/swap.c:95
 release_pages+0x5d5/0x1940 mm/swap.c:762
 free_pages_and_swap_cache+0x2a0/0x3d0 mm/swap_state.c:295
 tlb_flush_mmu_free+0x4e/0x120 mm/mmu_gather.c:74
 zap_pte_range mm/memory.c:1158 [inline]
 zap_pmd_range mm/memory.c:1193 [inline]
 zap_pud_range mm/memory.c:1222 [inline]
 zap_p4d_range mm/memory.c:1243 [inline]
 unmap_page_range+0x180e/0x2330 mm/memory.c:1264
 unmap_single_vma+0x19d/0x300 mm/memory.c:1309
 unmap_vmas+0x115/0x250 mm/memory.c:1340
 exit_mmap+0x2c2/0x530 mm/mmap.c:3138
 __mmput kernel/fork.c:1046 [inline]
 mmput+0x15f/0x4c0 kernel/fork.c:1067
 exit_mm kernel/exit.c:546 [inline]
 do_exit+0x816/0x2fa0 kernel/exit.c:863
 do_group_exit+0x135/0x370 kernel/exit.c:980
 get_signal+0x399/0x1d50 kernel/signal.c:2575
 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_32_irqs_on arch/x86/entry/common.c:341 [inline]
 do_fast_syscall_32+0xa9d/0xc98 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f8c869
Code: Bad RIP value.
RSP: 002b:00000000f5d880cc EFLAGS: 00000296 ORIG_RAX: 0000000000000159
RAX: 0000000000000002 RBX: 0000000000000008 RCX: 0000000020003d40
RDX: 0000000000000002 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 8032:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505
 slab_post_alloc_hook mm/slab.h:436 [inline]
 slab_alloc mm/slab.c:3392 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3554
 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/0x1935 net/dccp/input.c:680
 dccp_v6_do_rcv+0x269/0xbf0 net/dccp/ipv6.c:641
 sk_backlog_rcv include/net/sock.h:937 [inline]
 __release_sock+0x12e/0x3a0 net/core/sock.c:2413
 release_sock+0x59/0x1c0 net/core/sock.c:2929
 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:1685
 __do_sys_connect net/socket.c:1696 [inline]
 __se_sys_connect net/socket.c:1693 [inline]
 __ia32_sys_connect+0x72/0xb0 net/socket.c:1693
 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
 do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Freed by task 8036:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3764
 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:293

The buggy address belongs to the object at ffff88806413d640
 which belongs to the cache ccid2_hc_tx_sock of size 1240
The buggy address is located 0 bytes inside of
 1240-byte region [ffff88806413d640, ffff88806413db18)
The buggy address belongs to the page:
page:ffffea0001904f00 count:1 mapcount:0 mapping:ffff888216f9ecc0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffff88809b374048 ffff88809b374048 ffff888216f9ecc0
raw: 0000000000000000 ffff88806413c040 0000000100000005 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806413d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806413d580: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88806413d600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                           ^
 ffff88806413d680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806413d700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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