R13: 000000000000000b R14: 00007f7b41d9bf80 R15: 00007fff3f034098 dccp_parse_options: DCCP(ffff88801f89a040): Option 32 (len=7) error=9 ================================================================== BUG: KASAN: slab-use-after-free in dccp_ackvec_runlen net/dccp/ccids/../ackvec.h:43 [inline] BUG: KASAN: slab-use-after-free in ccid2_hc_tx_packet_recv+0x1902/0x2070 net/dccp/ccids/ccid2.c:592 Read of size 1 at addr ffff8880780b8494 by task syz-executor.0/5481 CPU: 1 PID: 5481 Comm: syz-executor.0 Not tainted 6.8.0-rc4-syzkaller-g7e90b5c295ec #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x167/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x180 mm/kasan/report.c:601 dccp_ackvec_runlen net/dccp/ccids/../ackvec.h:43 [inline] ccid2_hc_tx_packet_recv+0x1902/0x2070 net/dccp/ccids/ccid2.c:592 ccid_hc_tx_packet_recv net/dccp/ccid.h:189 [inline] dccp_deliver_input_to_ccids net/dccp/input.c:182 [inline] dccp_rcv_established+0x295/0x320 net/dccp/input.c:374 dccp_v4_do_rcv+0xff/0x1f0 net/dccp/ipv4.c:675 sk_backlog_rcv include/net/sock.h:1092 [inline] __release_sock+0x243/0x350 net/core/sock.c:2973 release_sock+0x61/0x1f0 net/core/sock.c:3539 dccp_sendmsg+0x4de/0xb70 net/dccp/proto.c:803 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmmsg+0x3b2/0x740 net/socket.c:2724 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f7b41c7ad39 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7b42e220c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f7b41d9bf80 RCX: 00007f7b41c7ad39 RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000005 RBP: 00007f7b42e22120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 000000000000000b R14: 00007f7b41d9bf80 R15: 00007fff3f034098 Allocated by task 5481: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:372 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:389 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:3981 [inline] __kmalloc_node_track_caller+0x249/0x4e0 mm/slub.c:4001 kmalloc_reserve+0xf3/0x260 net/core/skbuff.c:582 __alloc_skb+0x1b1/0x420 net/core/skbuff.c:651 alloc_skb include/linux/skbuff.h:1296 [inline] dccp_send_ack+0xaa/0x310 net/dccp/output.c:585 ccid2_hc_rx_packet_recv+0x10c/0x1c0 net/dccp/ccids/ccid2.c:771 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline] dccp_deliver_input_to_ccids net/dccp/input.c:176 [inline] dccp_rcv_established+0x1bb/0x320 net/dccp/input.c:374 dccp_v4_do_rcv+0xff/0x1f0 net/dccp/ipv4.c:675 sk_backlog_rcv include/net/sock.h:1092 [inline] __sk_receive_skb+0x823/0x8a0 net/core/sock.c:568 ip_protocol_deliver_rcu+0x2e0/0x430 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2b6/0x500 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5534 [inline] __netif_receive_skb+0x2bf/0x6a0 net/core/dev.c:5648 process_backlog+0x385/0x760 net/core/dev.c:5976 __napi_poll+0xcb/0x490 net/core/dev.c:6576 napi_poll net/core/dev.c:6645 [inline] net_rx_action+0x78b/0x1010 net/core/dev.c:6778 __do_softirq+0x2bb/0x942 kernel/softirq.c:553 Freed by task 5481: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x4e/0x60 mm/kasan/generic.c:640 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:241 __kasan_slab_free+0x34/0x70 mm/kasan/common.c:257 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kfree+0x14a/0x380 mm/slub.c:4409 skb_kfree_head net/core/skbuff.c:986 [inline] skb_free_head net/core/skbuff.c:998 [inline] skb_release_data+0x666/0x850 net/core/skbuff.c:1028 skb_release_all net/core/skbuff.c:1094 [inline] __kfree_skb net/core/skbuff.c:1108 [inline] kfree_skb_reason+0x195/0x390 net/core/skbuff.c:1144 kfree_skb include/linux/skbuff.h:1244 [inline] dccp_v4_do_rcv+0x143/0x1f0 net/dccp/ipv4.c:710 sk_backlog_rcv include/net/sock.h:1092 [inline] __release_sock+0x243/0x350 net/core/sock.c:2973 release_sock+0x61/0x1f0 net/core/sock.c:3539 dccp_sendmsg+0x4de/0xb70 net/dccp/proto.c:803 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmmsg+0x3b2/0x740 net/socket.c:2724 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 The buggy address belongs to the object at ffff8880780b8000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1172 bytes inside of freed 2048-byte region [ffff8880780b8000, ffff8880780b8800) The buggy address belongs to the physical page: page:ffffea0001e02e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x780b8 head:ffffea0001e02e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888014c42000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5481, tgid 5480 (syz-executor.0), ts 90839901552, free_ts 60223581298 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311 __alloc_pages+0x255/0x680 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd17/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] __do_kmalloc_node mm/slub.c:3980 [inline] __kmalloc_node_track_caller+0x2d1/0x4e0 mm/slub.c:4001 kmalloc_reserve+0xf3/0x260 net/core/skbuff.c:582 __alloc_skb+0x1b1/0x420 net/core/skbuff.c:651 alloc_skb include/linux/skbuff.h:1296 [inline] dccp_send_ack+0xaa/0x310 net/dccp/output.c:585 ccid2_hc_rx_packet_recv+0x10c/0x1c0 net/dccp/ccids/ccid2.c:771 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline] dccp_deliver_input_to_ccids net/dccp/input.c:176 [inline] dccp_rcv_established+0x1bb/0x320 net/dccp/input.c:374 dccp_v4_do_rcv+0xff/0x1f0 net/dccp/ipv4.c:675 sk_backlog_rcv include/net/sock.h:1092 [inline] __sk_receive_skb+0x823/0x8a0 net/core/sock.c:568 ip_protocol_deliver_rcu+0x2e0/0x430 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2b6/0x500 net/ipv4/ip_input.c:233 page last free pid 5072 tgid 5072 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 vfree+0x186/0x2e0 mm/vmalloc.c:2842 kcov_put kernel/kcov.c:429 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:525 __fput+0x429/0x8a0 fs/file_table.c:376 task_work_run+0x24e/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa2c/0x2740 kernel/exit.c:871 do_group_exit+0x206/0x2c0 kernel/exit.c:1020 get_signal+0x176d/0x1850 kernel/signal.c:2893 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc8/0x370 kernel/entry/common.c:212 do_syscall_64+0x108/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6f/0x77 Memory state around the buggy address: ffff8880780b8380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880780b8400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880780b8480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880780b8500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880780b8580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================