cron (5993) used greatest stack depth: 15744 bytes left hrtimer: interrupt took 45747 ns hrtimer: interrupt took 48541 ns ================================================================== BUG: KASAN: use-after-free in ccid_hc_tx_delete+0xe0/0x100 net/dccp/ccid.c:188 Read of size 8 at addr ffff8881c1894b80 by task syz-executor074/6032 CPU: 1 PID: 6032 Comm: syz-executor074 Not tainted 4.20.0-rc6+ #373 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 kernel tried to execute NX-protected page - exploit attempt? (uid: 0) Call Trace: BUG: unable to handle kernel paging request at ffff8881c17d2e80 PGD be01067 P4D be01067 PUD 1d940d063 PMD 80000001c16001e3 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 Oops: 0011 [#1] PREEMPT SMP KASAN CPU: 0 PID: 6031 Comm: syz-executor074 Not tainted 4.20.0-rc6+ #373 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0xffff8881c17d2e80 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <40> e4 fe d1 81 88 ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 RSP: 0018:ffff8881dae06ba8 EFLAGS: 00010206 RAX: ffff8881b381e180 RBX: ffff8881c1894b80 RCX: ffffffff873face6 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 RDX: 0000000000000100 RSI: ffffffff873fac83 RDI: ffff8881b2fff440 ccid_hc_tx_delete+0xe0/0x100 net/dccp/ccid.c:188 RBP: ffff8881dae06bd0 R08: ffff8881b381e180 R09: 0000000000000000 dccp_hdlr_ccid+0x7d/0x150 net/dccp/feat.c:53 R10: ffffed103b5c5b5f R11: ffff8881dae2dafb R12: ffff8881d21564c0 __dccp_feat_activate+0x188/0x280 net/dccp/feat.c:344 R13: ffff8881c17d2e80 R14: ffff8881b2fff440 R15: 0000000000000001 FS: 00007f3d93ed0700(0000) GS:ffff8881dae00000(0000) knlGS:0000000000000000 dccp_feat_activate_values+0x3c1/0x80a net/dccp/feat.c:1538 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff8881c17d2e80 CR3: 00000001c15b8000 CR4: 00000000001406f0 Call Trace: dccp_create_openreq_child+0x47a/0x630 net/dccp/minisocks.c:127 dccp_hdlr_ccid+0x7d/0x150 net/dccp/feat.c:53 __dccp_feat_activate+0x188/0x280 net/dccp/feat.c:344 dccp_feat_activate_values+0x3c1/0x80a net/dccp/feat.c:1538 dccp_v6_request_recv_sock+0x278/0x2020 net/dccp/ipv6.c:466 dccp_create_openreq_child+0x47a/0x630 net/dccp/minisocks.c:127 dccp_check_req+0x47d/0x6d0 net/dccp/minisocks.c:196 dccp_v6_request_recv_sock+0x278/0x2020 net/dccp/ipv6.c:466 dccp_v6_rcv+0x874/0x1ce9 net/dccp/ipv6.c:744 ip6_input_finish+0x3fc/0x1aa0 net/ipv6/ip6_input.c:384 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:427 dccp_check_req+0x47d/0x6d0 net/dccp/minisocks.c:196 dccp_v6_rcv+0x874/0x1ce9 net/dccp/ipv6.c:744 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x115/0x640 net/ipv6/ip6_input.c:272 ip6_input_finish+0x3fc/0x1aa0 net/ipv6/ip6_input.c:384 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4946 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:427 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5056 process_backlog+0x24e/0x7a0 net/core/dev.c:5864 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76 napi_poll net/core/dev.c:6287 [inline] net_rx_action+0x7fa/0x19b0 net/core/dev.c:6353 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x115/0x640 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4946 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5056 process_backlog+0x24e/0x7a0 net/core/dev.c:5864 napi_poll net/core/dev.c:6287 [inline] net_rx_action+0x7fa/0x19b0 net/core/dev.c:6353 __do_softirq+0x308/0xb7e kernel/softirq.c:292 __do_softirq+0x308/0xb7e kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.14+0x126/0x160 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x21d/0x260 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip6_finish_output2+0xcef/0x2940 net/ipv6/ip6_output.c:121 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 ip6_finish_output+0x58c/0xc60 net/ipv6/ip6_output.c:154 do_softirq.part.14+0x126/0x160 kernel/softirq.c:337 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x21d/0x260 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip6_finish_output2+0xcef/0x2940 net/ipv6/ip6_output.c:121 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip6_xmit+0xf1c/0x2510 net/ipv6/ip6_output.c:275 ip6_finish_output+0x58c/0xc60 net/ipv6/ip6_output.c:154 inet6_csk_xmit+0x375/0x630 net/ipv6/inet6_connection_sock.c:139 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip6_xmit+0xf1c/0x2510 net/ipv6/ip6_output.c:275 dccp_transmit_skb+0x98c/0x12e0 net/dccp/output.c:142 dccp_send_ack+0x1d9/0x360 net/dccp/output.c:595 dccp_rcv_request_sent_state_process net/dccp/input.c:501 [inline] dccp_rcv_state_process+0x152e/0x1b7e net/dccp/input.c:680 dccp_v6_do_rcv+0x271/0xbf0 net/dccp/ipv6.c:638 inet6_csk_xmit+0x375/0x630 net/ipv6/inet6_connection_sock.c:139 sk_backlog_rcv include/net/sock.h:932 [inline] __release_sock+0x12f/0x3a0 net/core/sock.c:2276 release_sock+0xad/0x2c0 net/core/sock.c:2789 inet_wait_for_connect net/ipv4/af_inet.c:588 [inline] __inet_stream_connect+0x641/0x1150 net/ipv4/af_inet.c:680 dccp_transmit_skb+0x98c/0x12e0 net/dccp/output.c:142 dccp_send_ack+0x1d9/0x360 net/dccp/output.c:595 dccp_rcv_request_sent_state_process net/dccp/input.c:501 [inline] dccp_rcv_state_process+0x152e/0x1b7e net/dccp/input.c:680 inet_stream_connect+0x58/0xa0 net/ipv4/af_inet.c:719 dccp_v6_do_rcv+0x271/0xbf0 net/dccp/ipv6.c:638 __sys_connect+0x37d/0x4c0 net/socket.c:1664 sk_backlog_rcv include/net/sock.h:932 [inline] __release_sock+0x12f/0x3a0 net/core/sock.c:2276 release_sock+0xad/0x2c0 net/core/sock.c:2789 inet_wait_for_connect net/ipv4/af_inet.c:588 [inline] __inet_stream_connect+0x641/0x1150 net/ipv4/af_inet.c:680 __do_sys_connect net/socket.c:1675 [inline] __se_sys_connect net/socket.c:1672 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1672 inet_stream_connect+0x58/0xa0 net/ipv4/af_inet.c:719 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 __sys_connect+0x37d/0x4c0 net/socket.c:1664 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4466c9 __do_sys_connect net/socket.c:1675 [inline] __se_sys_connect net/socket.c:1672 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1672 Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 RSP: 002b:00007f3d93e8dda8 EFLAGS: 00000297 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00000000006dbc68 RCX: 00000000004466c9 RDX: 000000000000001c RSI: 0000000020419000 RDI: 0000000000000006 RBP: 00000000006dbc60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dbc6c R13: 616e732f7665642f R14: 0100000000000000 R15: 00000000006dbd4c Allocated by task 6018: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 entry_SYSCALL_64_after_hwframe+0x49/0xbe set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 RIP: 0033:0x4466c9 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554 RSP: 002b:00007f3d93ecfda8 EFLAGS: 00000297 ORIG_RAX: 000000000000002a ccid_new+0x25b/0x3e0 net/dccp/ccid.c:151 RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004466c9 dccp_hdlr_ccid+0x27/0x150 net/dccp/feat.c:44 RDX: 000000000000001c RSI: 0000000020419000 RDI: 0000000000000006 __dccp_feat_activate+0x188/0x280 net/dccp/feat.c:344 RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000 dccp_feat_activate_values+0x3c1/0x80a net/dccp/feat.c:1538 R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dbc4c dccp_rcv_request_sent_state_process net/dccp/input.c:472 [inline] dccp_rcv_state_process+0x1320/0x1b7e net/dccp/input.c:680 R13: 616e732f7665642f R14: 0100000000000000 R15: 00000000006dbd4c dccp_v6_do_rcv+0x271/0xbf0 net/dccp/ipv6.c:638 Modules linked in: sk_backlog_rcv include/net/sock.h:932 [inline] __release_sock+0x12f/0x3a0 net/core/sock.c:2276 CR2: ffff8881c17d2e80 release_sock+0xad/0x2c0 net/core/sock.c:2789 ---[ end trace b846078fc75beec3 ]--- inet_wait_for_connect net/ipv4/af_inet.c:588 [inline] __inet_stream_connect+0x641/0x1150 net/ipv4/af_inet.c:680 RIP: 0010:0xffff8881c17d2e80 inet_stream_connect+0x58/0xa0 net/ipv4/af_inet.c:719 Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <40> e4 fe d1 81 88 ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 __sys_connect+0x37d/0x4c0 net/socket.c:1664 RSP: 0018:ffff8881dae06ba8 EFLAGS: 00010206 __do_sys_connect net/socket.c:1675 [inline] __se_sys_connect net/socket.c:1672 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1672 RAX: ffff8881b381e180 RBX: ffff8881c1894b80 RCX: ffffffff873face6 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 RDX: 0000000000000100 RSI: ffffffff873fac83 RDI: ffff8881b2fff440 entry_SYSCALL_64_after_hwframe+0x49/0xbe RBP: ffff8881dae06bd0 R08: ffff8881b381e180 R09: 0000000000000000 R10: ffffed103b5c5b5f R11: ffff8881dae2dafb R12: ffff8881d21564c0 Freed by task 6033: R13: ffff8881c17d2e80 R14: ffff8881b2fff440 R15: 0000000000000001 save_stack+0x43/0xd0 mm/kasan/kasan.c:448 FS: 00007f3d93ed0700(0000) GS:ffff8881dae00000(0000) knlGS:0000000000000000 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 CR2: ffff8881c17d2e80 CR3: 00000001c15b8000 CR4: 00000000001406f0 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3760