一、漏洞信息
漏洞编号：CVE-2024-44946
漏洞归属组件：kernel
漏洞归属的版本：4.19.140,4.19.194,4.19.90,5.10.0,6.1.0,6.1.14,6.1.19,6.1.5,6.1.6,6.1.8,6.4.0,6.6.0
CVSS V2.0分值：
BaseScore：0.0 None
Vector：CVSS：2.0/
漏洞简述：
In the Linux kernel, the following vulnerability has been resolved:kcm: Serialise kcm_sendmsg() for the same socket.syzkaller reported UAF in kcm_release(). [0]The scenario is 1. Thread A builds a skb with MSG_MORE and sets kcm->seq_skb. 2. Thread A resumes building skb from kcm->seq_skb but is blocked by sk_stream_wait_memory() 3. Thread B calls sendmsg() concurrently, finishes building kcm->seq_skb and puts the skb to the write queue 4. Thread A faces an error and finally frees skb that is already in the write queue 5. kcm_release() does double-free the skb in the write queueWhen a thread is building a MSG_MORE skb, another thread must not touch it.Let s add a per-sk mutex and serialise kcm_sendmsg().[0]:BUG: KASAN: slab-use-after-free in __skb_unlink include/linux/skbuff.h:2366 [inline]BUG: KASAN: slab-use-after-free in __skb_dequeue include/linux/skbuff.h:2385 [inline]BUG: KASAN: slab-use-after-free in __skb_queue_purge_reason include/linux/skbuff.h:3175 [inline]BUG: KASAN: slab-use-after-free in __skb_queue_purge include/linux/skbuff.h:3181 [inline]BUG: KASAN: slab-use-after-free in kcm_release+0x170/0x4c8 net/kcm/kcmsock.c:1691Read of size 8 at addr ffff0000ced0fc80 by task syz-executor329/6167CPU: 1 PID: 6167 Comm: syz-executor329 Tainted: G B 6.8.0-rc5-syzkaller-g9abbc24128bc #0Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x178/0x518 mm/kasan/report.c:488 kasan_report+0xd8/0x138 mm/kasan/report.c:601 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 __skb_unlink include/linux/skbuff.h:2366 [inline] __skb_dequeue include/linux/skbuff.h:2385 [inline] __skb_queue_purge_reason include/linux/skbuff.h:3175 [inline] __skb_queue_purge include/linux/skbuff.h:3181 [inline] kcm_release+0x170/0x4c8 net/kcm/kcmsock.c:1691 __sock_release net/socket.c:659 [inline] sock_close+0xa4/0x1e8 net/socket.c:1421 __fput+0x30c/0x738 fs/file_table.c:376 ____fput+0x20/0x30 fs/file_table.c:404 task_work_run+0x230/0x2e0 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x618/0x1f64 kernel/exit.c:871 do_group_exit+0x194/0x22c kernel/exit.c:1020 get_signal+0x1500/0x15ec kernel/signal.c:2893 do_signal+0x23c/0x3b44 arch/arm64/kernel/signal.c:1249 do_notify_resume+0x74/0x1f4 arch/arm64/kernel/entry-common.c:148 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:713 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598Allocated by task 6166: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_alloc_info+0x70/0x84 mm/kasan/generic.c:626 unpoison_slab_object mm/kasan/common.c:314 [inline] __kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_node+0x204/0x4c0 mm/slub.c:3903 __alloc_skb+0x19c/0x3d8 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1296 [inline] kcm_sendmsg+0x1d3c/0x2124 net/kcm/kcmsock.c:783 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_sendmsg+0x220/0x2c0 net/socket.c:768 splice_to_socket+0x7cc/0xd58 fs/splice.c:889 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0xec/0x1d8 fs/splice.c:1164 splice_direct_to_actor+0x438/0xa0c fs/splice.c:1108 do_splice_direct_actor ---truncated---
漏洞公开时间：2024-08-31 22:15:04
漏洞创建时间：2024-09-01 06:26:08
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2024-44946

漏洞分析指导链接：
https://gitee.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
漏洞数据来源:
openBrain开源漏洞感知系统
漏洞补丁信息：

二、漏洞分析结构反馈
影响性分析说明：

openEuler评分：

受影响版本排查(受影响/不受影响)：
1.master(6.1.0):
2.openEuler-20.03-LTS-SP4(4.19.90):
3.openEuler-22.03-LTS-SP1(5.10.0):
4.openEuler-22.03-LTS-SP3(5.10.0):
5.openEuler-22.03-LTS-SP4(5.10.0):
6.openEuler-24.03-LTS(6.6.0):
7.openEuler-24.03-LTS-Next(6.6.0):

修复是否涉及abi变化(是/否)：
1.master(6.1.0):
2.openEuler-20.03-LTS-SP4(4.19.90):
3.openEuler-22.03-LTS-SP1(5.10.0):
4.openEuler-22.03-LTS-SP3(5.10.0):
5.openEuler-22.03-LTS-SP4(5.10.0):
6.openEuler-24.03-LTS(6.6.0):
7.openEuler-24.03-LTS-Next(6.6.0):