================================================================== BUG: KASAN: use-after-free in memcpy include/linux/fortify-string.h:191 [inline] BUG: KASAN: use-after-free in skb_copy_from_linear_data_offset include/linux/skbuff.h:3676 [inline] BUG: KASAN: use-after-free in skb_segment+0x14ba/0x37a0 net/core/skbuff.c:4000 Read of size 4095 at addr ffff88806bf7293f by task syz-executor.3/22890 CPU: 1 PID: 22890 Comm: syz-executor.3 Not tainted 5.11.0-rc4-next-20210120-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230 __kasan_report mm/kasan/report.c:397 [inline] kasan_report.cold+0x79/0xd5 mm/kasan/report.c:414 check_region_inline mm/kasan/generic.c:180 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:186 memcpy+0x20/0x60 mm/kasan/shadow.c:65 memcpy include/linux/fortify-string.h:191 [inline] skb_copy_from_linear_data_offset include/linux/skbuff.h:3676 [inline] skb_segment+0x14ba/0x37a0 net/core/skbuff.c:4000 tcp_gso_segment+0x33d/0x17e0 net/ipv4/tcp_offload.c:98 tcp4_gso_segment net/ipv4/tcp_offload.c:51 [inline] tcp4_gso_segment+0x194/0x3a0 net/ipv4/tcp_offload.c:29 inet_gso_segment+0x502/0x1110 net/ipv4/af_inet.c:1378 skb_mac_gso_segment+0x26e/0x530 net/core/dev.c:3326 __skb_gso_segment+0x330/0x6e0 net/core/dev.c:3399 skb_gso_segment include/linux/netdevice.h:4712 [inline] cake_enqueue+0x2808/0x39f0 net/sched/sch_cake.c:1742 __dev_xmit_skb net/core/dev.c:3807 [inline] __dev_queue_xmit+0x1913/0x2dd0 net/core/dev.c:4119 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0xeb6/0x21b0 net/ipv4/ip_output.c:230 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x396/0x640 net/ipv4/ip_output.c:290 ip_finish_output+0x35/0x200 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:290 [inline] ip_output+0x196/0x310 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:441 [inline] ip_local_out net/ipv4/ip_output.c:126 [inline] __ip_queue_xmit+0x8e9/0x1a00 net/ipv4/ip_output.c:532 __tcp_transmit_skb+0x188c/0x38f0 net/ipv4/tcp_output.c:1405 tcp_transmit_skb net/ipv4/tcp_output.c:1423 [inline] tcp_write_xmit+0xde7/0x6140 net/ipv4/tcp_output.c:2689 tcp_sendmsg_locked+0xa1c/0x2e40 net/ipv4/tcp.c:1410 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1459 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:817 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 __sys_sendto+0x21c/0x320 net/socket.c:1975 __do_sys_sendto net/socket.c:1987 [inline] __se_sys_sendto net/socket.c:1983 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:1983 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007faa5cefec68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045e219 RDX: ffffffffffffff94 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 000000000119c080 R08: 0000000000000000 R09: fffffffffffffed3 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007fff393d5a6f R14: 00007faa5ceff9c0 R15: 000000000119c034 Allocated by task 10733: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:403 [inline] ____kasan_kmalloc mm/kasan/common.c:434 [inline] ____kasan_kmalloc.constprop.0+0xa0/0xd0 mm/kasan/common.c:406 kmalloc_node include/linux/slab.h:579 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:587 kvmalloc include/linux/mm.h:782 [inline] xt_alloc_table_info+0x3c/0xa0 net/netfilter/x_tables.c:1176 do_replace net/ipv6/netfilter/ip6_tables.c:1141 [inline] do_ip6t_set_ctl+0x4e5/0xb70 net/ipv6/netfilter/ip6_tables.c:1636 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1008 tcp_setsockopt+0x136/0x2440 net/ipv4/tcp.c:3598 __sys_setsockopt+0x2db/0x610 net/socket.c:2115 __do_sys_setsockopt net/socket.c:2126 [inline] __se_sys_setsockopt net/socket.c:2123 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2123 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 10733: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free.part.0+0xe1/0x110 mm/kasan/common.c:364 kasan_slab_free include/linux/kasan.h:191 [inline] slab_free_hook mm/slub.c:1565 [inline] slab_free_freelist_hook+0x82/0x1d0 mm/slub.c:1603 slab_free mm/slub.c:3164 [inline] kfree+0xe5/0x7b0 mm/slub.c:4205 kvfree+0x42/0x50 mm/util.c:616 __do_replace+0x6b7/0x8c0 net/ipv6/netfilter/ip6_tables.c:1103 do_replace net/ipv6/netfilter/ip6_tables.c:1156 [inline] do_ip6t_set_ctl+0x8ec/0xb70 net/ipv6/netfilter/ip6_tables.c:1636 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1008 tcp_setsockopt+0x136/0x2440 net/ipv4/tcp.c:3598 __sys_setsockopt+0x2db/0x610 net/socket.c:2115 __do_sys_setsockopt net/socket.c:2126 [inline] __se_sys_setsockopt net/socket.c:2123 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2123 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88806bf72800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 319 bytes inside of 1024-byte region [ffff88806bf72800, ffff88806bf72c00) The buggy address belongs to the page: page:00000000bf3de719 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6bf70 head:00000000bf3de719 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head) raw: 00fff00000010200 ffffea0000507400 0000000400000004 ffff888010041dc0 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806bf72800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806bf72880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806bf72900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806bf72980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806bf72a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================