KASAN: use-after-free Write in enqueue_to

Kernel	Title	Rank 🛈	Count	Last	Reported	Patched	Status
upstream	KASAN: use-after-free Read in enqueue_to_backlog net	19	6	1397d	1508d	0/29	closed as invalid on 2022/11/15 21:20
android-5-10	KASAN: use-after-free Read in enqueue_to_backlog	19	1	34d	34d	0/2	premoderation: reported on 2026/05/14 07:31
linux-6.1	KASAN: use-after-free Read in enqueue_to_backlog	19	1	27d	27d	0/3	upstream: reported on 2026/05/20 14:09

new mount options do not match the existing superblock, will be ignored IPVS: ftp: loaded support on port[0] = 21 ================================================================== BUG: KASAN: use-after-free in __write_once_size include/linux/compiler.h:290 [inline] BUG: KASAN: use-after-free in __skb_insert include/linux/skbuff.h:1763 [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 enqueue_to_backlog+0xddc/0xe00 net/core/dev.c:4239 Write of size 8 at addr ffff88802003c080 by task syz-executor.2/7489 CPU: 1 PID: 7489 Comm: syz-executor.2 Not tainted 4.19.211-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:290 [inline] __skb_insert include/linux/skbuff.h:1763 [inline] __skb_queue_before include/linux/skbuff.h:1869 [inline] __skb_queue_tail include/linux/skbuff.h:1903 [inline] enqueue_to_backlog+0xddc/0xe00 net/core/dev.c:4239 netif_rx_internal+0xfd/0x670 net/core/dev.c:4491 veth_forward_skb drivers/net/veth.c:176 [inline] veth_xmit+0x1eb/0x800 drivers/net/veth.c:203 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [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 macvlan_queue_xmit drivers/net/macvlan.c:545 [inline] macvlan_start_xmit+0x19a/0x7e0 drivers/net/macvlan.c:570 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [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 neigh_hh_output include/net/neighbour.h:491 [inline] neigh_output include/net/neighbour.h:499 [inline] ip_finish_output2+0xb6d/0x15a0 net/ipv4/ip_output.c:230 ip_finish_output+0xae9/0x10b0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_mc_output+0x268/0xec0 net/ipv4/ip_output.c:391 dst_output include/net/dst.h:455 [inline] ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:125 ip_send_skb+0x3e/0xe0 net/ipv4/ip_output.c:1452 udp_send_skb+0x6a4/0x1170 net/ipv4/udp.c:848 udp_sendmsg+0x1cb4/0x2550 net/ipv4/udp.c:1135 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2227 __sys_sendmmsg+0x195/0x470 net/socket.c:2322 __do_sys_sendmmsg net/socket.c:2351 [inline] __se_sys_sendmmsg net/socket.c:2348 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2348 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fccaeab5eb9 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:00007fccad40a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fccaebc9030 RCX: 00007fccaeab5eb9 RDX: 04000000000000a8 RSI: 00000000200038c0 RDI: 0000000000000004 RBP: 00007fccaeb1008d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff1181411f R14: 00007fccad40a300 R15: 0000000000022000 Allocated by task 7489: kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 skb_clone+0x151/0x3d0 net/core/skbuff.c:1293 dev_queue_xmit_nit+0x326/0xa20 net/core/dev.c:2018 xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0xaa/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 macvlan_queue_xmit drivers/net/macvlan.c:545 [inline] macvlan_start_xmit+0x19a/0x7e0 drivers/net/macvlan.c:570 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [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 neigh_hh_output include/net/neighbour.h:491 [inline] neigh_output include/net/neighbour.h:499 [inline] ip_finish_output2+0xb6d/0x15a0 net/ipv4/ip_output.c:230 ip_finish_output+0xae9/0x10b0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_mc_output+0x268/0xec0 net/ipv4/ip_output.c:391 dst_output include/net/dst.h:455 [inline] ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:125 ip_send_skb+0x3e/0xe0 net/ipv4/ip_output.c:1452 udp_send_skb+0x6a4/0x1170 net/ipv4/udp.c:848 udp_sendmsg+0x1cb4/0x2550 net/ipv4/udp.c:1135 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2227 __sys_sendmmsg+0x195/0x470 net/socket.c:2322 __do_sys_sendmmsg net/socket.c:2351 [inline] __se_sys_sendmmsg net/socket.c:2348 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2348 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7489: __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 packet_rcv+0xea/0x1490 net/packet/af_packet.c:2148 dev_queue_xmit_nit+0x756/0xa20 net/core/dev.c:2050 xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0xaa/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 macvlan_queue_xmit drivers/net/macvlan.c:545 [inline] macvlan_start_xmit+0x19a/0x7e0 drivers/net/macvlan.c:570 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [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 neigh_hh_output include/net/neighbour.h:491 [inline] neigh_output include/net/neighbour.h:499 [inline] ip_finish_output2+0xb6d/0x15a0 net/ipv4/ip_output.c:230 ip_finish_output+0xae9/0x10b0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_mc_output+0x268/0xec0 net/ipv4/ip_output.c:391 dst_output include/net/dst.h:455 [inline] ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:125 ip_send_skb+0x3e/0xe0 net/ipv4/ip_output.c:1452 udp_send_skb+0x6a4/0x1170 net/ipv4/udp.c:848 udp_sendmsg+0x1cb4/0x2550 net/ipv4/udp.c:1135 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2227 __sys_sendmmsg+0x195/0x470 net/socket.c:2322 __do_sys_sendmmsg net/socket.c:2351 [inline] __se_sys_sendmmsg net/socket.c:2348 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2348 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 ffff88802003c080 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 0 bytes inside of 232-byte region [ffff88802003c080, ffff88802003c168) The buggy address belongs to the page: page:ffffea0000800f00 count:1 mapcount:0 mapping:ffff8880b5b8fd80 index:0x0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea00028cbb08 ffffea00006c9b08 ffff8880b5b8fd80 raw: 0000000000000000 ffff88802003c080 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88802003bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802003c000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802003c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802003c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff88802003c180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================