fail_dump lib/fault-inject.c:52 [inline] should_fail.cold.4+0x5/0x17 lib/fault-inject.c:144 __should_failslab+0xba/0xf0 mm/failslab.c:33 ================================================================== should_failslab+0x9/0x14 mm/slab_common.c:1788 slab_pre_alloc_hook mm/slab.h:567 [inline] slab_alloc mm/slab.c:3306 [inline] kmem_cache_alloc_trace+0x2c3/0x760 mm/slab.c:3549 BUG: KASAN: use-after-free in ccid2_hc_tx_packet_recv+0x1f0f/0x2235 net/dccp/ccids/ccid2.c:587 Read of size 1 at addr ffff8881cd459482 by task syz-executor2/6662 kmalloc include/linux/slab.h:555 [inline] dccp_feat_entry_new+0x140/0x360 net/dccp/feat.c:462 dccp_feat_push_confirm+0x26/0x280 net/dccp/feat.c:510 dccp_feat_handle_nn_established net/dccp/feat.c:1339 [inline] dccp_feat_parse_options+0xf99/0x1a30 net/dccp/feat.c:1424 dccp_parse_options+0x85b/0x1000 net/dccp/options.c:124 dccp_rcv_established+0x23/0x70 net/dccp/input.c:370 dccp_v4_do_rcv+0xf4/0x160 net/dccp/ipv4.c:655 sk_backlog_rcv include/net/sock.h:963 [inline] __release_sock+0x110/0x340 net/core/sock.c:2440 release_sock+0x4f/0x180 net/core/sock.c:2956 dccp_sendmsg+0x52f/0xdb0 net/dccp/proto.c:814 inet_sendmsg+0xbd/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xdf/0x110 net/socket.c:672 ____sys_sendmsg+0x3f8/0xae0 net/socket.c:2343 ___sys_sendmsg+0xe4/0x160 net/socket.c:2397 __sys_sendmmsg+0x160/0x380 net/socket.c:2487 __do_sys_sendmmsg net/socket.c:2516 [inline] __se_sys_sendmmsg net/socket.c:2513 [inline] __x64_sys_sendmmsg+0x98/0x100 net/socket.c:2513 do_syscall_64+0xd0/0x630 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b59 Code: 1d ba 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 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3b9fec1c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f3b9fec26d4 RCX: 0000000000455b59 RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000005 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 000000000000057a R14: 00000000006fc410 R15: 000000000000000d CPU: 1 PID: 6662 Comm: syz-executor2 Not tainted 5.6.0-rc5-syzkaller #0 dccp_parse_options: DCCP(00000000c8102299): Option 32 (len=7) error=9 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+0x12f/0x187 lib/dump_stack.c:118 print_address_description.constprop.8+0x3b/0x60 mm/kasan/report.c:374 __kasan_report.cold.11+0x1b/0x32 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:641 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132 ccid2_hc_tx_packet_recv+0x1f0f/0x2235 net/dccp/ccids/ccid2.c:587 ccid_hc_tx_packet_recv net/dccp/ccid.h:189 [inline] dccp_deliver_input_to_ccids+0x1a9/0x220 net/dccp/input.c:182 dccp_rcv_established+0x49/0x70 net/dccp/input.c:374 dccp_v4_do_rcv+0xf4/0x160 net/dccp/ipv4.c:655 sk_backlog_rcv include/net/sock.h:963 [inline] __release_sock+0x110/0x340 net/core/sock.c:2440 release_sock+0x4f/0x180 net/core/sock.c:2956 dccp_sendmsg+0x52f/0xdb0 net/dccp/proto.c:814 inet_sendmsg+0xbd/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xdf/0x110 net/socket.c:672 ____sys_sendmsg+0x3f8/0xae0 net/socket.c:2343 ___sys_sendmsg+0xe4/0x160 net/socket.c:2397 __sys_sendmmsg+0x160/0x380 net/socket.c:2487 __do_sys_sendmmsg net/socket.c:2516 [inline] __se_sys_sendmmsg net/socket.c:2513 [inline] __x64_sys_sendmmsg+0x98/0x100 net/socket.c:2513 do_syscall_64+0xd0/0x630 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b59 Code: 1d ba 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 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f6bc566fc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f6bc56706d4 RCX: 0000000000455b59 RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000005 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 000000000000057a R14: 00000000006fc410 R15: 000000000000000d Allocated by task 6662: save_stack+0x21/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc.constprop.7+0xc1/0xd0 mm/kasan/common.c:515 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529 __do_kmalloc_node mm/slab.c:3616 [inline] __kmalloc_node_track_caller+0x4d/0x70 mm/slab.c:3630 __kmalloc_reserve.isra.49+0x2c/0xc0 net/core/skbuff.c:142 __alloc_skb+0xd7/0x570 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1081 [inline] dccp_send_ack+0xb3/0x340 net/dccp/output.c:576 ccid2_hc_rx_packet_recv+0xf9/0x170 net/dccp/ccids/ccid2.c:766 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline] dccp_deliver_input_to_ccids+0xcc/0x220 net/dccp/input.c:176 dccp_rcv_established+0x49/0x70 net/dccp/input.c:374 dccp_v4_do_rcv+0xf4/0x160 net/dccp/ipv4.c:655 sk_backlog_rcv include/net/sock.h:963 [inline] __sk_receive_skb+0x2b6/0x9e0 net/core/sock.c:519 dccp_v4_rcv+0xc22/0x1c0b net/dccp/ipv4.c:876 ip_protocol_deliver_rcu+0x50b/0x6b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x1ee/0x2e0 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x306/0x450 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x171/0x270 net/ipv4/ip_input.c:428 NF_HOOK include/linux/netfilter.h:307 [inline] ip_rcv+0xcb/0x2f0 net/ipv4/ip_input.c:538 __netif_receive_skb_one_core+0x132/0x190 net/core/dev.c:5187 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5301 process_backlog+0x1f1/0x700 net/core/dev.c:6133 napi_poll net/core/dev.c:6571 [inline] net_rx_action+0x42d/0xde0 net/core/dev.c:6639 __do_softirq+0x248/0x94c kernel/softirq.c:292 Freed by task 6662: save_stack+0x21/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:337 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/common.c:476 kasan_slab_free+0xe/0x10 mm/kasan/common.c:485 __cache_free mm/slab.c:3426 [inline] kfree+0xfa/0x290 mm/slab.c:3757 skb_free_head+0x6e/0x90 net/core/skbuff.c:590 skb_release_data+0x36d/0x6a0 net/core/skbuff.c:610 skb_release_all+0x3d/0x50 net/core/skbuff.c:664 __kfree_skb net/core/skbuff.c:678 [inline] kfree_skb+0xa9/0x2a0 net/core/skbuff.c:696 dccp_v4_do_rcv+0x10b/0x160 net/dccp/ipv4.c:690 sk_backlog_rcv include/net/sock.h:963 [inline] __release_sock+0x110/0x340 net/core/sock.c:2440 release_sock+0x4f/0x180 net/core/sock.c:2956 dccp_sendmsg+0x52f/0xdb0 net/dccp/proto.c:814 inet_sendmsg+0xbd/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xdf/0x110 net/socket.c:672 ____sys_sendmsg+0x3f8/0xae0 net/socket.c:2343 ___sys_sendmsg+0xe4/0x160 net/socket.c:2397 __sys_sendmmsg+0x160/0x380 net/socket.c:2487 __do_sys_sendmmsg net/socket.c:2516 [inline] __se_sys_sendmmsg net/socket.c:2513 [inline] __x64_sys_sendmmsg+0x98/0x100 net/socket.c:2513 do_syscall_64+0xd0/0x630 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881cd459000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1154 bytes inside of 2048-byte region [ffff8881cd459000, ffff8881cd459800) The buggy address belongs to the page: page:ffffea0007351640 refcount:1 mapcount:0 mapping:ffff8881da000e00 index:0x0 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea00073516c8 ffffea0006fd92c8 ffff8881da000e00 raw: 0000000000000000 ffff8881cd459000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881cd459380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cd459400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881cd459480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881cd459500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cd459580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================