Ack Vector buffer overflow: dropping old entries at net/dccp/ackvec.c:231/dccp_ackvec_add_new() ================================================================== 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 ffff8880896db88d by task syz-executor.5/16144 CPU: 1 PID: 16144 Comm: syz-executor.5 Not tainted 5.0.0-rc6+ #70 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:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132 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_v6_do_rcv+0x9a9/0xbf0 net/dccp/ipv6.c:609 sk_backlog_rcv include/net/sock.h:936 [inline] __sk_receive_skb+0x341/0xbf0 net/core/sock.c:473 dccp_v6_rcv+0xd45/0x191e net/dccp/ipv6.c:778 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 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x211/0x270 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+0xbcf/0x2550 net/ipv6/ip6_output.c:121 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip6_xmit+0xe41/0x20c0 net/ipv6/ip6_output.c:275 inet6_csk_xmit+0x2fb/0x5d0 net/ipv6/inet6_connection_sock.c:139 dccp_transmit_skb+0x977/0x12c0 net/dccp/output.c:142 dccp_send_close+0x206/0x355 net/dccp/output.c:703 dccp_terminate_connection net/dccp/proto.c:987 [inline] dccp_close+0x98e/0xe80 net/dccp/proto.c:1050 inet_release+0x105/0x1f0 net/ipv4/af_inet.c:428 inet6_release+0x53/0x80 net/ipv6/af_inet6.c:473 __sock_release+0xd3/0x250 net/socket.c:579 sock_close+0x1b/0x30 net/socket.c:1139 __fput+0x2df/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x411d31 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 94 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:0000000000a4fd90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000411d31 RDX: 0000000000000000 RSI: 0000000000741b68 RDI: 0000000000000005 RBP: 0000000000000000 R08: 000000000004ff3c R09: 000000000004ff3c R10: 0000000000a4fcc0 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000156 R15: 0000000000000005 Allocated by task 16165: 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_node mm/slab.c:3673 [inline] __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3687 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:140 __alloc_skb+0x10b/0x5e0 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1011 [inline] dccp_send_ack+0xd6/0x360 net/dccp/output.c:580 dccp_rcv_request_sent_state_process net/dccp/input.c:501 [inline] dccp_rcv_state_process+0x1372/0x1931 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 16165: 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] kfree+0xcf/0x230 mm/slab.c:3806 skb_free_head+0x93/0xb0 net/core/skbuff.c:553 skb_release_data+0x57e/0x7b0 net/core/skbuff.c:573 skb_release_all+0x4d/0x60 net/core/skbuff.c:627 __kfree_skb+0x16/0x30 net/core/skbuff.c:641 dccp_rcv_state_process+0x3aa/0x1931 net/dccp/input.c:713 dccp_child_process+0x1ba/0x8b0 net/dccp/minisocks.c:228 dccp_v6_rcv+0x704/0x191e net/dccp/ipv6.c:754 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 ffff8880896db400 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1165 bytes inside of 2048-byte region [ffff8880896db400, ffff8880896dbc00) The buggy address belongs to the page: page:ffffea000225b680 count:1 mapcount:0 mapping:ffff88812c3f0c40 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002933808 ffffea0002244e88 ffff88812c3f0c40 raw: 0000000000000000 ffff8880896da300 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880896db780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880896db800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880896db880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ 8021q: adding VLAN 0 to HW filter on device team0 ffff8880896db900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880896db980: 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