一、漏洞信息
漏洞编号：CVE-2022-48969
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 V3.0分值：
BaseScore：5.5 Medium
Vector：CVSS：3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
漏洞简述：
In the Linux kernel, the following vulnerability has been resolved:xen-netfront: Fix NULL sring after live migrationA NAPI is setup for each network sring to poll data to kernelThe sring with source host is destroyed before live migration andnew sring with target host is setup after live migration.The NAPI for the old sring is not deleted until setup new sringwith target host after migration. With busy_poll/busy_read enabled,the NAPI can be polled before got deleted when resume VM.BUG: unable to handle kernel NULL pointer dereference at0000000000000008IP: xennet_poll+0xae/0xd20PGD 0 P4D 0Oops: 0000 [#1] SMP PTICall Trace: finish_task_switch+0x71/0x230 timerqueue_del+0x1d/0x40 hrtimer_try_to_cancel+0xb5/0x110 xennet_alloc_rx_buffers+0x2a0/0x2a0 napi_busy_loop+0xdb/0x270 sock_poll+0x87/0x90 do_sys_poll+0x26f/0x580 tracing_map_insert+0x1d4/0x2f0 event_hist_trigger+0x14a/0x260 finish_task_switch+0x71/0x230 __schedule+0x256/0x890 recalc_sigpending+0x1b/0x50 xen_sched_clock+0x15/0x20 __rb_reserve_next+0x12d/0x140 ring_buffer_lock_reserve+0x123/0x3d0 event_triggers_call+0x87/0xb0 trace_event_buffer_commit+0x1c4/0x210 xen_clocksource_get_cycles+0x15/0x20 ktime_get_ts64+0x51/0xf0 SyS_ppoll+0x160/0x1a0 SyS_ppoll+0x160/0x1a0 do_syscall_64+0x73/0x130 entry_SYSCALL_64_after_hwframe+0x41/0xa6...RIP: xennet_poll+0xae/0xd20 RSP: ffffb4f041933900CR2: 0000000000000008---[ end trace f8601785b354351c ]---xen frontend should remove the NAPIs for the old srings before livemigration as the bond srings are destroyedThere is a tiny window between the srings are set to NULL andthe NAPIs are disabled, It is safe as the NAPI threads are stillfrozen at that time
漏洞公开时间：2024-10-22 04:15:09
漏洞创建时间：2024-10-22 08:01:55
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2022-48969

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：
In the Linux kernel, the following vulnerability has been resolved:xen-netfront: Fix NULL sring after live migrationA NAPI is setup for each network sring to poll data to kernelThe sring with source host is destroyed before live migration andnew sring with target host is setup after live migration.The NAPI for the old sring is not deleted until setup new sringwith target host after migration. With busy_poll/busy_read enabled,the NAPI can be polled before got deleted when resume VM.BUG: unable to handle kernel NULL pointer dereference at0000000000000008IP: xennet_poll+0xae/0xd20PGD 0 P4D 0Oops: 0000 [#1] SMP PTICall Trace: finish_task_switch+0x71/0x230 timerqueue_del+0x1d/0x40 hrtimer_try_to_cancel+0xb5/0x110 xennet_alloc_rx_buffers+0x2a0/0x2a0 napi_busy_loop+0xdb/0x270 sock_poll+0x87/0x90 do_sys_poll+0x26f/0x580 tracing_map_insert+0x1d4/0x2f0 event_hist_trigger+0x14a/0x260 finish_task_switch+0x71/0x230 __schedule+0x256/0x890 recalc_sigpending+0x1b/0x50 xen_sched_clock+0x15/0x20 __rb_reserve_next+0x12d/0x140 ring_buffer_lock_reserve+0x123/0x3d0 event_triggers_call+0x87/0xb0 trace_event_buffer_commit+0x1c4/0x210 xen_clocksource_get_cycles+0x15/0x20 ktime_get_ts64+0x51/0xf0 SyS_ppoll+0x160/0x1a0 SyS_ppoll+0x160/0x1a0 do_syscall_64+0x73/0x130 entry_SYSCALL_64_after_hwframe+0x41/0xa6...RIP: xennet_poll+0xae/0xd20 RSP: ffffb4f041933900CR2: 0000000000000008---[ end trace f8601785b354351c ]---xen frontend should remove the NAPIs for the old srings before livemigration as the bond srings are destroyedThere is a tiny window between the srings are set to NULL andthe NAPIs are disabled, It is safe as the NAPI threads are stillfrozen at that time
openEuler评分：
5.5
Vector：CVSS：3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
受影响版本排查(受影响/不受影响)：
1.openEuler-20.03-LTS-SP4(4.19.90):受影响
2.openEuler-22.03-LTS-SP1(5.10.0):受影响
3.openEuler-22.03-LTS-SP3(5.10.0):不受影响
4.openEuler-22.03-LTS-SP4(5.10.0):不受影响
5.master(6.6.0):不受影响
6.openEuler-24.03-LTS(6.6.0):不受影响
7.openEuler-24.03-LTS-Next(6.6.0):不受影响
8.openEuler-24.03-LTS-SP1(6.6.0):不受影响

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

原因说明：
1.openEuler-22.03-LTS-SP1(5.10.0):正常修复
2.openEuler-20.03-LTS-SP4(4.19.90):不修复-超出修复范围
3.openEuler-22.03-LTS-SP3(5.10.0):不受影响-漏洞代码不存在
4.openEuler-22.03-LTS-SP4(5.10.0):不受影响-漏洞代码不存在
5.master(6.6.0):不受影响-漏洞代码不存在
6.openEuler-24.03-LTS(6.6.0):不受影响-漏洞代码不存在
7.openEuler-24.03-LTS-Next(6.6.0):不受影响-漏洞代码不存在
8.openEuler-24.03-LTS-SP1(6.6.0):不受影响-漏洞代码不存在

三、漏洞修复
安全公告链接：https://www.openeuler.org/zh/security/safety-bulletin/detail/?id=openEuler-SA-2024-2491