CVE-2024-36886 tipc: fix UAF in error path
In the Linux kernel, the following vulnerability has been resolved:

tipc: fix UAF in error path

Sam Page (sam4k) working with Trend Micro Zero Day Initiative reported
a UAF in the tipc_buf_append() error path:

BUG: KASAN: slab-use-after-free in kfree_skb_list_reason+0x47e/0x4c0
linux/net/core/skbuff.c:1183
Read of size 8 at addr ffff88804d2a7c80 by task poc/8034

CPU: 1 PID: 8034 Comm: poc Not tainted 6.8.2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.0-debian-1.16.0-5 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack linux/lib/dump_stack.c:88
 dump_stack_lvl+0xd9/0x1b0 linux/lib/dump_stack.c:106
 print_address_description linux/mm/kasan/report.c:377
 print_report+0xc4/0x620 linux/mm/kasan/report.c:488
 kasan_report+0xda/0x110 linux/mm/kasan/report.c:601
 kfree_skb_list_reason+0x47e/0x4c0 linux/net/core/skbuff.c:1183
 skb_release_data+0x5af/0x880 linux/net/core/skbuff.c:1026
 skb_release_all linux/net/core/skbuff.c:1094
 __kfree_skb linux/net/core/skbuff.c:1108
 kfree_skb_reason+0x12d/0x210 linux/net/core/skbuff.c:1144
 kfree_skb linux/./include/linux/skbuff.h:1244
 tipc_buf_append+0x425/0xb50 linux/net/tipc/msg.c:186
 tipc_link_input+0x224/0x7c0 linux/net/tipc/link.c:1324
 tipc_link_rcv+0x76e/0x2d70 linux/net/tipc/link.c:1824
 tipc_rcv+0x45f/0x10f0 linux/net/tipc/node.c:2159
 tipc_udp_recv+0x73b/0x8f0 linux/net/tipc/udp_media.c:390
 udp_queue_rcv_one_skb+0xad2/0x1850 linux/net/ipv4/udp.c:2108
 udp_queue_rcv_skb+0x131/0xb00 linux/net/ipv4/udp.c:2186
 udp_unicast_rcv_skb+0x165/0x3b0 linux/net/ipv4/udp.c:2346
 __udp4_lib_rcv+0x2594/0x3400 linux/net/ipv4/udp.c:2422
 ip_protocol_deliver_rcu+0x30c/0x4e0 linux/net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2e4/0x520 linux/net/ipv4/ip_input.c:233
 NF_HOOK linux/./include/linux/netfilter.h:314
 NF_HOOK linux/./include/linux/netfilter.h:308
 ip_local_deliver+0x18e/0x1f0 linux/net/ipv4/ip_input.c:254
 dst_input linux/./include/net/dst.h:461
 ip_rcv_finish linux/net/ipv4/ip_input.c:449
 NF_HOOK linux/./include/linux/netfilter.h:314
 NF_HOOK linux/./include/linux/netfilter.h:308
 ip_rcv+0x2c5/0x5d0 linux/net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core+0x199/0x1e0 linux/net/core/dev.c:5534
 __netif_receive_skb+0x1f/0x1c0 linux/net/core/dev.c:5648
 process_backlog+0x101/0x6b0 linux/net/core/dev.c:5976
 __napi_poll.constprop.0+0xba/0x550 linux/net/core/dev.c:6576
 napi_poll linux/net/core/dev.c:6645
 net_rx_action+0x95a/0xe90 linux/net/core/dev.c:6781
 __do_softirq+0x21f/0x8e7 linux/kernel/softirq.c:553
 do_softirq linux/kernel/softirq.c:454
 do_softirq+0xb2/0xf0 linux/kernel/softirq.c:441
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 linux/kernel/softirq.c:381
 local_bh_enable linux/./include/linux/bottom_half.h:33
 rcu_read_unlock_bh linux/./include/linux/rcupdate.h:851
 __dev_queue_xmit+0x871/0x3ee0 linux/net/core/dev.c:4378
 dev_queue_xmit linux/./include/linux/netdevice.h:3169
 neigh_hh_output linux/./include/net/neighbour.h:526
 neigh_output linux/./include/net/neighbour.h:540
 ip_finish_output2+0x169f/0x2550 linux/net/ipv4/ip_output.c:235
 __ip_finish_output linux/net/ipv4/ip_output.c:313
 __ip_finish_output+0x49e/0x950 linux/net/ipv4/ip_output.c:295
 ip_finish_output+0x31/0x310 linux/net/ipv4/ip_output.c:323
 NF_HOOK_COND linux/./include/linux/netfilter.h:303
 ip_output+0x13b/0x2a0 linux/net/ipv4/ip_output.c:433
 dst_output linux/./include/net/dst.h:451
 ip_local_out linux/net/ipv4/ip_output.c:129
 ip_send_skb+0x3e5/0x560 linux/net/ipv4/ip_output.c:1492
 udp_send_skb+0x73f/0x1530 linux/net/ipv4/udp.c:963
 udp_sendmsg+0x1a36/0x2b40 linux/net/ipv4/udp.c:1250
 inet_sendmsg+0x105/0x140 linux/net/ipv4/af_inet.c:850
 sock_sendmsg_nosec linux/net/socket.c:730
 __sock_sendmsg linux/net/socket.c:745
 __sys_sendto+0x42c/0x4e0 linux/net/socket.c:2191
 __do_sys_sendto linux/net/socket.c:2203
 __se_sys_sendto linux/net/socket.c:2199
 __x64_sys_sendto+0xe0/0x1c0 linux/net/socket.c:2199
 do_syscall_x64 linux/arch/x86/entry/common.c:52
 do_syscall_
---truncated---
CVSS v3.1 score: 9.8