netlink: 16 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 2 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 2 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 16 bytes leftover after parsing attributes in process `syz-executor6'. ================================================================== BUG: KASAN: use-after-free in ccid2_hc_tx_rto_expire+0x51c/0x5c0 net/dccp/ccids/ccid2.c:144 Read of size 4 at addr ffff8801cd973180 by task syz-fuzzer/3005 CPU: 0 PID: 3005 Comm: syz-fuzzer Not tainted 4.13.0-rc5+ #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429 ccid2_hc_tx_rto_expire+0x51c/0x5c0 net/dccp/ccids/ccid2.c:144 call_timer_fn+0x233/0x830 kernel/time/timer.c:1268 expire_timers kernel/time/timer.c:1307 [inline] __run_timers+0x7fd/0xb90 kernel/time/timer.c:1601 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614 __do_softirq+0x2f5/0xba3 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:638 [inline] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:1044 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:702 RIP: 0033:0x40cd2b RSP: 002b:000000c429bc9b68 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff10 RAX: 000000c4201824b0 RBX: 000000c4201824b0 RCX: 0000000000016265 RDX: 00000000008688a0 RSI: 00000000c2a4c185 RDI: 0000000000000000 RBP: 000000c429bc9b80 R08: 000000000000001b R09: 000000c42001c2a8 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000003ad R13: 00000000000000f9 R14: 00000000000000f9 R15: 0000000000000000 Allocated by task 26651: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x127/0x750 mm/slab.c:3561 ccid_new+0x20e/0x390 net/dccp/ccid.c:151 dccp_hdlr_ccid+0x27/0x140 net/dccp/feat.c:44 __dccp_feat_activate+0x142/0x2a0 net/dccp/feat.c:344 dccp_feat_activate_values+0x34e/0xa90 net/dccp/feat.c:1538 dccp_create_openreq_child+0x474/0x600 net/dccp/minisocks.c:121 dccp_v4_request_recv_sock+0xaa/0x9c0 net/dccp/ipv4.c:408 dccp_v6_request_recv_sock+0xfb3/0x1aa0 net/dccp/ipv6.c:412 dccp_check_req+0x321/0x5a0 net/dccp/minisocks.c:190 dccp_v4_rcv+0x645/0x1c00 net/dccp/ipv4.c:837 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:248 [inline] ip_local_deliver+0x1ce/0x6d0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:478 [inline] ip_rcv_finish+0x8db/0x19c0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:248 [inline] ip_rcv+0xc3f/0x17d0 net/ipv4/ip_input.c:488 __netif_receive_skb_core+0x19af/0x33d0 net/core/dev.c:4418 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4456 process_backlog+0x203/0x740 net/core/dev.c:5132 napi_poll net/core/dev.c:5529 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5595 __do_softirq+0x2f5/0xba3 kernel/softirq.c:284 Freed by task 26692: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x77/0x280 mm/slab.c:3763 ccid_hc_tx_delete+0xc5/0x100 net/dccp/ccid.c:190 dccp_destroy_sock+0x2fb/0x460 net/dccp/proto.c:222 dccp_v6_destroy_sock+0x15/0x20 net/dccp/ipv6.c:994 inet_csk_destroy_sock+0x166/0x3f0 net/ipv4/inet_connection_sock.c:833 dccp_close+0x84d/0xc10 net/dccp/proto.c:1064 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:425 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:432 sock_release+0x8d/0x1e0 net/socket.c:597 sock_close+0x16/0x20 net/socket.c:1126 __fput+0x327/0x7e0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:246 task_work_run+0x18a/0x260 kernel/task_work.c:116 exit_task_work include/linux/task_work.h:21 [inline] do_exit+0xa3a/0x1b10 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:969 get_signal+0x7e8/0x17e0 kernel/signal.c:2330 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:808 exit_to_usermode_loop+0x224/0x300 arch/x86/entry/common.c:157 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath+0x3a7/0x450 arch/x86/entry/common.c:263 entry_SYSCALL_64_fastpath+0xbc/0xbe The buggy address belongs to the object at ffff8801cd972d40 which belongs to the cache ccid2_hc_tx_sock of size 1240 The buggy address is located 1088 bytes inside of 1240-byte region [ffff8801cd972d40, ffff8801cd973218) The buggy address belongs to the page: page:ffffea0007365c80 count:1 mapcount:0 mapping:ffff8801cd972240 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801cd972240 0000000000000000 0000000100000005 raw: ffffea0006a3d020 ffffea00069638a0 ffff8801d3aaa9c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cd973080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cd973100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801cd973180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801cd973200: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801cd973280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================