RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 00000000000008a7 R14: 00000000004ca021 R15: 0000000000000004 dccp_parse_options: DCCP(0000000087890ae0): Option 32 (len=7) error=9 ================================================================== BUG: KASAN: use-after-free in ccid2_hc_tx_packet_recv+0x21cf/0x2240 net/dccp/ccids/ccid2.c:587 Read of size 1 at addr ffff88804737f494 by task syz-executor.0/15099 CPU: 1 PID: 15099 Comm: syz-executor.0 Not tainted 5.5.0-rc7-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:639 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132 ccid2_hc_tx_packet_recv+0x21cf/0x2240 net/dccp/ccids/ccid2.c:587 ccid_hc_tx_packet_recv net/dccp/ccid.h:189 [inline] dccp_deliver_input_to_ccids+0x1f8/0x270 net/dccp/input.c:182 dccp_rcv_established net/dccp/input.c:374 [inline] dccp_rcv_established+0x83/0xb0 net/dccp/input.c:364 dccp_v4_do_rcv+0x139/0x190 net/dccp/ipv4.c:655 sk_backlog_rcv include/net/sock.h:954 [inline] __release_sock+0x129/0x390 net/core/sock.c:2437 release_sock+0x59/0x1c0 net/core/sock.c:2953 dccp_sendmsg+0x6be/0xd20 net/dccp/proto.c:814 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:659 ____sys_sendmsg+0x358/0x880 net/socket.c:2330 ___sys_sendmsg+0x100/0x170 net/socket.c:2384 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2474 __do_sys_sendmmsg net/socket.c:2503 [inline] __se_sys_sendmmsg net/socket.c:2500 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2500 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b349 Code: ad b6 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fca7b44dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fca7b44e6d4 RCX: 000000000045b349 RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000005 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 00000000000008a7 R14: 00000000004ca021 R15: 0000000000000004 Allocated by task 15099: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527 __do_kmalloc_node mm/slab.c:3616 [inline] __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3630 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:141 __alloc_skb+0x10b/0x5e0 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1049 [inline] dccp_send_ack+0xd6/0x360 net/dccp/output.c:576 ccid2_hc_rx_packet_recv+0x139/0x1b0 net/dccp/ccids/ccid2.c:766 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline] dccp_deliver_input_to_ccids+0xeb/0x270 net/dccp/input.c:176 dccp_rcv_established net/dccp/input.c:374 [inline] dccp_rcv_established+0x83/0xb0 net/dccp/input.c:364 dccp_v4_do_rcv+0x139/0x190 net/dccp/ipv4.c:655 sk_backlog_rcv include/net/sock.h:954 [inline] __sk_receive_skb+0x335/0xc60 net/core/sock.c:519 dccp_v4_rcv+0xf7c/0x1dd2 net/dccp/ipv4.c:876 ip_protocol_deliver_rcu+0x5a/0x880 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x23b/0x380 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x1e9/0x520 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x1db/0x2f0 net/ipv4/ip_input.c:428 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:538 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:5150 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5264 process_backlog+0x206/0x750 net/core/dev.c:6095 napi_poll net/core/dev.c:6532 [inline] net_rx_action+0x508/0x1120 net/core/dev.c:6600 __do_softirq+0x262/0x98c kernel/softirq.c:292 Freed by task 15099: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 skb_free_head+0x93/0xb0 net/core/skbuff.c:591 skb_release_data+0x551/0x8d0 net/core/skbuff.c:611 skb_release_all+0x4d/0x60 net/core/skbuff.c:665 __kfree_skb net/core/skbuff.c:679 [inline] kfree_skb net/core/skbuff.c:697 [inline] kfree_skb+0x101/0x420 net/core/skbuff.c:691 dccp_v4_do_rcv net/dccp/ipv4.c:690 [inline] dccp_v4_do_rcv+0x160/0x190 net/dccp/ipv4.c:650 sk_backlog_rcv include/net/sock.h:954 [inline] __release_sock+0x129/0x390 net/core/sock.c:2437 release_sock+0x59/0x1c0 net/core/sock.c:2953 dccp_sendmsg+0x6be/0xd20 net/dccp/proto.c:814 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:659 ____sys_sendmsg+0x358/0x880 net/socket.c:2330 ___sys_sendmsg+0x100/0x170 net/socket.c:2384 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2474 __do_sys_sendmmsg net/socket.c:2503 [inline] __se_sys_sendmmsg net/socket.c:2500 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2500 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88804737f000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1172 bytes inside of 2048-byte region [ffff88804737f000, ffff88804737f800) The buggy address belongs to the page: page:ffffea00011cdfc0 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 raw: 00fffe0000000200 ffffea0000c36748 ffffea000107b008 ffff8880aa400e00 raw: 0000000000000000 ffff88804737f000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88804737f380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804737f400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804737f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804737f500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804737f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================