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KASAN: use-after-free Write in skb_queue_tail

Status: auto-closed as invalid on 2021/10/05 02:17
Reported-by: syzbot+aa2a09784e3835154996@syzkaller.appspotmail.com
First crash: 1556d, last: 1556d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Write in skb_queue_tail net arm-msm 24 1 1827d 1827d 15/29 fixed on 2020/10/10 01:52
upstream general protection fault in skb_queue_tail (2) wireless 2 2 1507d 1516d 0/29 auto-closed as invalid on 2021/10/23 19:22
upstream general protection fault in skb_queue_tail (3) afs 19 C inconclusive done 9 830d 1063d 23/29 fixed on 2023/09/28 17:51
upstream general protection fault in skb_queue_tail (4) bluetooth 2 1 22d 18d 0/29 moderation: reported on 2025/08/22 15:06

Sample crash report:
Process accounting resumed
==================================================================
BUG: KASAN: use-after-free in __write_once_size include/linux/compiler.h:288 [inline]
BUG: KASAN: use-after-free in __skb_insert include/linux/skbuff.h:1760 [inline]
BUG: KASAN: use-after-free in __skb_queue_before include/linux/skbuff.h:1869 [inline]
BUG: KASAN: use-after-free in __skb_queue_tail include/linux/skbuff.h:1903 [inline]
BUG: KASAN: use-after-free in skb_queue_tail+0x11a/0x140 net/core/skbuff.c:2940
Write of size 8 at addr ffff888000101080 by task syz-executor.4/5261

CPU: 0 PID: 5261 Comm: syz-executor.4 Not tainted 4.19.193-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+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_store8_noabort+0x88/0x90 mm/kasan/report.c:438
 __write_once_size include/linux/compiler.h:288 [inline]
 __skb_insert include/linux/skbuff.h:1760 [inline]
 __skb_queue_before include/linux/skbuff.h:1869 [inline]
 __skb_queue_tail include/linux/skbuff.h:1903 [inline]
 skb_queue_tail+0x11a/0x140 net/core/skbuff.c:2940
 __netlink_sendskb net/netlink/af_netlink.c:1264 [inline]
 netlink_broadcast_deliver net/netlink/af_netlink.c:1389 [inline]
 do_one_broadcast net/netlink/af_netlink.c:1474 [inline]
 netlink_broadcast_filtered+0x74b/0xbc0 net/netlink/af_netlink.c:1518
 netlink_broadcast+0x35/0x40 net/netlink/af_netlink.c:1542
 nlmsg_multicast include/net/netlink.h:591 [inline]
 xfrm_nlmsg_multicast net/xfrm/xfrm_user.c:1091 [inline]
 xfrm_send_acquire+0x81b/0xac0 net/xfrm/xfrm_user.c:2977
 km_query+0xc5/0x210 net/xfrm/xfrm_state.c:2023
 xfrm_state_find+0x1d21/0x2d90 net/xfrm/xfrm_state.c:1042
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1410 [inline]
 xfrm_tmpl_resolve+0x2f3/0xc20 net/xfrm/xfrm_policy.c:1455
 xfrm_resolve_and_create_bundle+0xd8/0x3e0 net/xfrm/xfrm_policy.c:1753
 xfrm_lookup_with_ifid+0x232/0x1c40 net/xfrm/xfrm_policy.c:2076
 xfrm_lookup net/xfrm/xfrm_policy.c:2200 [inline]
 xfrm_lookup_route+0x36/0x1e0 net/xfrm/xfrm_policy.c:2211
 ip6_dst_lookup_flow+0x159/0x1d0 net/ipv6/ip6_output.c:1124
 rawv6_sendmsg+0xc65/0x36a0 net/ipv6/raw.c:931
 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2115
 __sys_sendmmsg+0x195/0x470 net/socket.c:2210
 __do_sys_sendmmsg net/socket.c:2239 [inline]
 __se_sys_sendmmsg net/socket.c:2236 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2236
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4665d9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efd88fae188 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9
RDX: 00000000000002e9 RSI: 0000000020000480 RDI: 0000000000000006
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001f4 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffd057548df R14: 00007efd88fae300 R15: 0000000000022000

Allocated by task 5261:
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 skb_clone+0x151/0x3d0 net/core/skbuff.c:1293
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:296 [inline]
 __netlink_deliver_tap net/netlink/af_netlink.c:321 [inline]
 netlink_deliver_tap+0x955/0xb00 net/netlink/af_netlink.c:334
 __netlink_sendskb net/netlink/af_netlink.c:1262 [inline]
 netlink_broadcast_deliver net/netlink/af_netlink.c:1389 [inline]
 do_one_broadcast net/netlink/af_netlink.c:1474 [inline]
 netlink_broadcast_filtered+0x73c/0xbc0 net/netlink/af_netlink.c:1518
 netlink_broadcast+0x35/0x40 net/netlink/af_netlink.c:1542
 nlmsg_multicast include/net/netlink.h:591 [inline]
 xfrm_nlmsg_multicast net/xfrm/xfrm_user.c:1091 [inline]
 xfrm_send_acquire+0x81b/0xac0 net/xfrm/xfrm_user.c:2977
 km_query+0xc5/0x210 net/xfrm/xfrm_state.c:2023
 xfrm_state_find+0x1d21/0x2d90 net/xfrm/xfrm_state.c:1042
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1410 [inline]
 xfrm_tmpl_resolve+0x2f3/0xc20 net/xfrm/xfrm_policy.c:1455
 xfrm_resolve_and_create_bundle+0xd8/0x3e0 net/xfrm/xfrm_policy.c:1753
 xfrm_lookup_with_ifid+0x232/0x1c40 net/xfrm/xfrm_policy.c:2076
 xfrm_lookup net/xfrm/xfrm_policy.c:2200 [inline]
 xfrm_lookup_route+0x36/0x1e0 net/xfrm/xfrm_policy.c:2211
 ip6_dst_lookup_flow+0x159/0x1d0 net/ipv6/ip6_output.c:1124
 rawv6_sendmsg+0xc65/0x36a0 net/ipv6/raw.c:931
 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2115
 __sys_sendmmsg+0x195/0x470 net/socket.c:2210
 __do_sys_sendmmsg net/socket.c:2239 [inline]
 __se_sys_sendmmsg net/socket.c:2236 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2236
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 5261:
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x7f/0x260 mm/slab.c:3765
 kfree_skbmem+0xc1/0x140 net/core/skbuff.c:595
 __kfree_skb net/core/skbuff.c:655 [inline]
 consume_skb+0x120/0x3d0 net/core/skbuff.c:714
 nlmon_xmit+0xdb/0x120 drivers/net/nlmon.c:25
 __netdev_start_xmit include/linux/netdevice.h:4345 [inline]
 netdev_start_xmit include/linux/netdevice.h:4359 [inline]
 xmit_one net/core/dev.c:3256 [inline]
 dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272
 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:303 [inline]
 __netlink_deliver_tap net/netlink/af_netlink.c:321 [inline]
 netlink_deliver_tap+0x8fb/0xb00 net/netlink/af_netlink.c:334
 __netlink_sendskb net/netlink/af_netlink.c:1262 [inline]
 netlink_broadcast_deliver net/netlink/af_netlink.c:1389 [inline]
 do_one_broadcast net/netlink/af_netlink.c:1474 [inline]
 netlink_broadcast_filtered+0x73c/0xbc0 net/netlink/af_netlink.c:1518
 netlink_broadcast+0x35/0x40 net/netlink/af_netlink.c:1542
 nlmsg_multicast include/net/netlink.h:591 [inline]
 xfrm_nlmsg_multicast net/xfrm/xfrm_user.c:1091 [inline]
 xfrm_send_acquire+0x81b/0xac0 net/xfrm/xfrm_user.c:2977
 km_query+0xc5/0x210 net/xfrm/xfrm_state.c:2023
 xfrm_state_find+0x1d21/0x2d90 net/xfrm/xfrm_state.c:1042
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1410 [inline]
 xfrm_tmpl_resolve+0x2f3/0xc20 net/xfrm/xfrm_policy.c:1455
 xfrm_resolve_and_create_bundle+0xd8/0x3e0 net/xfrm/xfrm_policy.c:1753
 xfrm_lookup_with_ifid+0x232/0x1c40 net/xfrm/xfrm_policy.c:2076
 xfrm_lookup net/xfrm/xfrm_policy.c:2200 [inline]
 xfrm_lookup_route+0x36/0x1e0 net/xfrm/xfrm_policy.c:2211
 ip6_dst_lookup_flow+0x159/0x1d0 net/ipv6/ip6_output.c:1124
 rawv6_sendmsg+0xc65/0x36a0 net/ipv6/raw.c:931
 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2115
 __sys_sendmmsg+0x195/0x470 net/socket.c:2210
 __do_sys_sendmmsg net/socket.c:2239 [inline]
 __se_sys_sendmmsg net/socket.c:2236 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2236
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888000101080
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 0 bytes inside of
 232-byte region [ffff888000101080, ffff888000101168)
The buggy address belongs to the page:
page:ffffea0000004040 count:1 mapcount:0 mapping:ffff8880b5b95d80 index:0x0
flags: 0x7ff00000000100(slab)
raw: 007ff00000000100 ffffea0002bcb448 ffffea0002a11a08 ffff8880b5b95d80
raw: 0000000000000000 ffff888000101080 000000010000000c 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888000100f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888000101000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888000101080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888000101100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff888000101180: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/06/07 02:16 linux-4.19.y 1722257b8ece 500c2339 .config console log report info ci2-linux-4-19 KASAN: use-after-free Write in skb_queue_tail
* Struck through repros no longer work on HEAD.