CVE-2023-52894

一、漏洞信息
 漏洞编号：[CVE-2023-52894](https://nvd.nist.gov/vuln/detail/CVE-2023-52894)
 漏洞归属组件：[kernel](https://gitee.com/src-openeuler/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:usb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()In Google internal bug 265639009 we ve received an (as yet) unreproduciblecrash report from an aarch64 GKI 5.10.149-android13 running device.AFAICT the source code is at:  https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10The call stack is:  ncm_close() -> ncm_notify() -> ncm_do_notify()with the crash at:  ncm_do_notify+0x98/0x270Code: 79000d0b b9000a6c f940012a f9400269 (b9405d4b)Which I believe disassembles to (I don t know ARM assembly, but it looks sane enough to me...):  // halfword (16-bit) store presumably to event->wLength (at offset 6 of struct usb_cdc_notification)  0B 0D 00 79    strh w11, [x8, #6]  // word (32-bit) store presumably to req->Length (at offset 8 of struct usb_request)  6C 0A 00 B9    str  w12, [x19, #8]  // x10 (NULL) was read here from offset 0 of valid pointer x9  // IMHO we re reading  cdev->gadget  and getting NULL  // gadget is indeed at offset 0 of struct usb_composite_dev  2A 01 40 F9    ldr  x10, [x9]  // loading req->buf pointer, which is at offset 0 of struct usb_request  69 02 40 F9    ldr  x9, [x19]  // x10 is null, crash, appears to be attempt to read cdev->gadget->max_speed  4B 5D 40 B9    ldr  w11, [x10, #0x5c]which seems to line up with ncm_do_notify() case NCM_NOTIFY_SPEED code fragment:  event->wLength = cpu_to_le16(8);  req->length = NCM_STATUS_BYTECOUNT;  /* SPEED_CHANGE data is up/down speeds in bits/sec */  data = req->buf + sizeof *event;  data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));My analysis of registers and NULL ptr deref crash offset  (Unable to handle kernel NULL pointer dereference at virtual address 000000000000005c)heavily suggests that the crash is due to  cdev->gadget  being NULL when executing:  data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));which calls:  ncm_bitrate(NULL)which then calls:  gadget_is_superspeed(NULL)which reads  ((struct usb_gadget *)NULL)->max_speedand hits a panic.AFAICT, if I m counting right, the offset of max_speed is indeed 0x5C.(remember there s a GKI KABI reservation of 16 bytes in struct work_struct)It s not at all clear to me how this is all supposed to work...but returning 0 seems much better than panic-ing...
 漏洞公开时间：2024-08-21 15:15:05
 漏洞创建时间：2024-08-21 23:45:49
 漏洞详情参考链接：
  https://nvd.nist.gov/vuln/detail/CVE-2023-52894
<details>
<summary>更多参考(点击展开)</summary>

| 参考来源 | 参考链接 | 来源链接 |
| ------- | -------- | -------- |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/09e4507ec8ef2d44da6ba4092b8ee2d81f216497 |  |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/63d161f29cd39c050e8873aa36e0c9fc013bb763 |  |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/a21da7f7aae618c785f7e4a275d43c06dc8412b6 |  |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/a69c8dfb85b44be9cc223be07d35cc3a9baefbea |  |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/c6ec929595c7443250b2a4faea988c62019d5cd2 |  |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/e92c70059178da751e5af7de02384b7dfadb5ec7 |  |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/fef6b29671b66dfb71f17e337c1ad14b5a2cedae |  |
| suse_bugzilla | http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-52894 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://www.cve.org/CVERecord?id=CVE-2023-52894 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/09e4507ec8ef2d44da6ba4092b8ee2d81f216497 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/63d161f29cd39c050e8873aa36e0c9fc013bb763 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/a21da7f7aae618c785f7e4a275d43c06dc8412b6 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/a69c8dfb85b44be9cc223be07d35cc3a9baefbea | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/c6ec929595c7443250b2a4faea988c62019d5cd2 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/e92c70059178da751e5af7de02384b7dfadb5ec7 | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/stable/c/fef6b29671b66dfb71f17e337c1ad14b5a2cedae | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| suse_bugzilla | https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2023/CVE-2023-52894.mbox | https://bugzilla.suse.com/show_bug.cgi?id=1229566 |
| ubuntu | https://www.cve.org/CVERecord?id=CVE-2023-52894 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/linus/c6ec929595c7443250b2a4faea988c62019d5cd2 (6.2-rc5) | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/fef6b29671b66dfb71f17e337c1ad14b5a2cedae | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/63d161f29cd39c050e8873aa36e0c9fc013bb763 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/a21da7f7aae618c785f7e4a275d43c06dc8412b6 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/e92c70059178da751e5af7de02384b7dfadb5ec7 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/a69c8dfb85b44be9cc223be07d35cc3a9baefbea | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/09e4507ec8ef2d44da6ba4092b8ee2d81f216497 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://git.kernel.org/stable/c/c6ec929595c7443250b2a4faea988c62019d5cd2 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://nvd.nist.gov/vuln/detail/CVE-2023-52894 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://launchpad.net/bugs/cve/CVE-2023-52894 | https://ubuntu.com/security/CVE-2023-52894 |
| ubuntu | https://security-tracker.debian.org/tracker/CVE-2023-52894 | https://ubuntu.com/security/CVE-2023-52894 |
| debian |  | https://security-tracker.debian.org/tracker/CVE-2023-52894 |

</details>

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：
  <details>
<summary>详情(点击展开)</summary>

| 影响的包 | 修复版本 | 修复补丁 | 问题引入补丁 | 来源  |
| ------- | -------- | ------- | -------- | --------- |
|  |  | https://git.kernel.org/stable/c/09e4507ec8ef2d44da6ba4092b8ee2d81f216497 |  | nvd |
|  |  | https://git.kernel.org/stable/c/63d161f29cd39c050e8873aa36e0c9fc013bb763 |  | nvd |
|  |  | https://git.kernel.org/stable/c/a21da7f7aae618c785f7e4a275d43c06dc8412b6 |  | nvd |
|  |  | https://git.kernel.org/stable/c/a69c8dfb85b44be9cc223be07d35cc3a9baefbea |  | nvd |
|  |  | https://git.kernel.org/stable/c/c6ec929595c7443250b2a4faea988c62019d5cd2 |  | nvd |
|  |  | https://git.kernel.org/stable/c/e92c70059178da751e5af7de02384b7dfadb5ec7 |  | nvd |
|  |  | https://git.kernel.org/stable/c/fef6b29671b66dfb71f17e337c1ad14b5a2cedae |  | nvd |
| linux |  | https://git.kernel.org/linus/c6ec929595c7443250b2a4faea988c62019d5cd2 | https://git.kernel.org/linus/1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | ubuntu |

</details>

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:usb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()In Google internal bug 265639009 we ve received an (as yet) unreproduciblecrash report from an aarch64 GKI 5.10.149-android13 running device.AFAICT the source code is at:  https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10The call stack is:  ncm_close() -> ncm_notify() -> ncm_do_notify()with the crash at:  ncm_do_notify+0x98/0x270Code: 79000d0b b9000a6c f940012a f9400269 (b9405d4b)Which I believe disassembles to (I don t know ARM assembly, but it looks sane enough to me...):  // halfword (16-bit) store presumably to event->wLength (at offset 6 of struct usb_cdc_notification)  0B 0D 00 79    strh w11, [x8, #6]  // word (32-bit) store presumably to req->Length (at offset 8 of struct usb_request)  6C 0A 00 B9    str  w12, [x19, #8]  // x10 (NULL) was read here from offset 0 of valid pointer x9  // IMHO we re reading  cdev->gadget  and getting NULL  // gadget is indeed at offset 0 of struct usb_composite_dev  2A 01 40 F9    ldr  x10, [x9]  // loading req->buf pointer, which is at offset 0 of struct usb_request  69 02 40 F9    ldr  x9, [x19]  // x10 is null, crash, appears to be attempt to read cdev->gadget->max_speed  4B 5D 40 B9    ldr  w11, [x10, #0x5c]which seems to line up with ncm_do_notify() case NCM_NOTIFY_SPEED code fragment:  event->wLength = cpu_to_le16(8);  req->length = NCM_STATUS_BYTECOUNT;  /* SPEED_CHANGE data is up/down speeds in bits/sec */  data = req->buf + sizeof *event;  data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));My analysis of registers and NULL ptr deref crash offset  (Unable to handle kernel NULL pointer dereference at virtual address 000000000000005c)heavily suggests that the crash is due to  cdev->gadget  being NULL when executing:  data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));which calls:  ncm_bitrate(NULL)which then calls:  gadget_is_superspeed(NULL)which reads  ((struct usb_gadget *)NULL)->max_speedand hits a panic.AFAICT, if I m counting right, the offset of max_speed is indeed 0x5C.(remember there s a GKI KABI reservation of 16 bytes in struct work_struct)It s not at all clear to me how this is all supposed to work...but returning 0 seems much better than panic-ing... 
 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

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

三、漏洞修复
安全公告链接：https://www.openeuler.org/zh/security/safety-bulletin/detail/?id=openEuler-SA-2024-2185

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**issue处理注意事项:** 
**1. 当前issue受影响的分支提交pr时, 须在pr描述中填写当前issue编号进行关联, 否则无法关闭当前issue;**
**2. 模板内容需要填写完整, 无论是受影响或者不受影响都需要填写完整内容,未引入的分支不需要填写, 否则无法关闭当前issue;**
**3. 以下为模板中需要填写完整的内容, 请复制到评论区回复, 注: 内容的标题名称(影响性分析说明, openEuler评分, 受影响版本排查(受影响/不受影响), 修复是否涉及abi变化(是/否))不能省略,省略后cve-manager将无法正常解析填写内容.**
************************************************************************
影响性分析说明:

openEuler评分: (评分和向量)

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):

-----------------------------------------------------------------------
issue处理具体操作请参考: 
https://gitee.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
pr关联issue具体操作请参考:
https://gitee.com/help/articles/4142

参考网址	关联pr	状态	补丁链接
https://nvd.nist.gov/vuln/detail/CVE-2023-52894	None	None	https://git.kernel.org/stable/c/c6ec929595c7443250b2a4faea988c62019d5cd2 https://git.kernel.org/stable/c/fef6b29671b66dfb71f17e337c1ad14b5a2cedae https://git.kernel.org/stable/c/a21da7f7aae618c785f7e4a275d43c06dc8412b6 https://git.kernel.org/stable/c/63d161f29cd39c050e8873aa36e0c9fc013bb763 https://git.kernel.org/stable/c/e92c70059178da751e5af7de02384b7dfadb5ec7 https://git.kernel.org/stable/c/09e4507ec8ef2d44da6ba4092b8ee2d81f216497 https://git.kernel.org/stable/c/a69c8dfb85b44be9cc223be07d35cc3a9baefbea
https://ubuntu.com/security/CVE-2023-52894	None	None	https://discourse.ubuntu.com/c/ubuntu-pro
https://www.opencve.io/cve/CVE-2023-52894	None	None	https://git.kernel.org/stable/c/c6ec929595c7443250b2a4faea988c62019d5cd2 https://git.kernel.org/stable/c/fef6b29671b66dfb71f17e337c1ad14b5a2cedae https://git.kernel.org/stable/c/a21da7f7aae618c785f7e4a275d43c06dc8412b6 https://git.kernel.org/stable/c/63d161f29cd39c050e8873aa36e0c9fc013bb763 https://git.kernel.org/stable/c/e92c70059178da751e5af7de02384b7dfadb5ec7 https://git.kernel.org/stable/c/09e4507ec8ef2d44da6ba4092b8ee2d81f216497 https://git.kernel.org/stable/c/a69c8dfb85b44be9cc223be07d35cc3a9baefbea
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2023-52894
https://security-tracker.debian.org/tracker/CVE-2023-52894

说明：补丁链接仅供初步排查参考，实际可用性请人工再次确认，补丁下载验证可使用CVE补丁工具。
若补丁不准确，烦请在此issue下评论 '/report-patch 参考网址补丁链接1,补丁链接2' 反馈正确信息，便于我们不断优化工具，不胜感激。
如 /report-patch https://security-tracker.debian.org/tracker/CVE-2021-3997 https://github.com/systemd/systemd/commit/5b1cf7a9be37e20133c0208005274ce4a5b5c6a1

CVE-2023-52894

影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()

In Google internal bug 265639009 we&#39;ve received an (as yet) unreproducible
crash report from an aarch64 GKI 5.10.149-android13 running device.

AFAICT the source code is at:
  <a
href="https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10">https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10</a>

The call stack is:
  ncm_close() -&gt; ncm_notify() -&gt; ncm_do_notify()
with the crash at:
  ncm_do_notify+0x98/0x270
Code: 79000d0b b9000a6c f940012a f9400269 (b9405d4b)

Which I believe disassembles to (I don&#39;t know ARM assembly, but it looks sane enough to me...):

// halfword (16-bit) store presumably to event-&gt;wLength (at offset 6 of struct usb_cdc_notification)
  0B 0D 00 79    strh w11, [x8, #6]

// word (32-bit) store presumably to req-&gt;Length (at offset 8 of struct usb_request)
  6C 0A 00 B9    str  w12, [x19, #8]

// x10 (NULL) was read here from offset 0 of valid pointer x9
  // IMHO we&#39;re reading &#39;cdev-&gt;gadget&#39; and getting NULL
  // gadget is indeed at offset 0 of struct usb_composite_dev
  2A 01 40 F9    ldr  x10, [x9]

// loading req-&gt;buf pointer, which is at offset 0 of struct usb_request
  69 02 40 F9    ldr  x9, [x19]

// x10 is null, crash, appears to be attempt to read cdev-&gt;gadget-&gt;max_speed
  4B 5D 40 B9    ldr  w11, [x10, #0x5c]

which seems to line up with ncm_do_notify() case NCM_NOTIFY_SPEED code fragment:

event-&gt;wLength = cpu_to_le16(8);
  req-&gt;length = NCM_STATUS_BYTECOUNT;

/* SPEED_CHANGE data is up/down speeds in bits/sec */
  data = req-&gt;buf + sizeof *event;
  data[0] = cpu_to_le32(ncm_bitrate(cdev-&gt;gadget));

My analysis of registers and NULL ptr deref crash offset
  (Unable to handle kernel NULL pointer dereference at virtual address 000000000000005c)
heavily suggests that the crash is due to &#39;cdev-&gt;gadget&#39; being NULL when executing:
  data[0] = cpu_to_le32(ncm_bitrate(cdev-&gt;gadget));
which calls:
  ncm_bitrate(NULL)
which then calls:
  gadget_is_superspeed(NULL)
which reads
  ((struct usb_gadget *)NULL)-&gt;max_speed
and hits a panic.

AFAICT, if I&#39;m counting right, the offset of max_speed is indeed 0x5C.
(remember there&#39;s a GKI KABI reservation of 16 bytes in struct work_struct)

It&#39;s not at all clear to me how this is all supposed to work...
but returning 0 seems much better than panic-ing...

The Linux kernel CVE team has assigned CVE-2023-52894 to this issue.

openEuler评分:(评分和向量)
3.9
AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L

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

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

@ 经过 cve-manager 解析, 已分析的内容如下表所示:
| 状态  | 需分析 | 内容 |
|:--:|:--:|---------|
|已分析|1.影响性分析说明|In the Linux kernel, the following vulnerability has been resolved:usb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()In Google internal bug 265639009 we&#39;ve received an (as yet) unreproduciblecrash report from an aarch64 GKI 5.10.149-android13 running device.AFAICT the source code is at:  <ahref="https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10">https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10</a>The call stack is:  ncm_close() -&gt; ncm_notify() -&gt; ncm_do_notify()with the crash at:  ncm_do_notify+0x98/0x270Code: 79000d0b b9000a6c f940012a f9400269 (b9405d4b)Which I believe disassembles to (I don&#39;t know ARM assembly, but it looks sane enough to me...):  // halfword (16-bit) store presumably to event-&gt;wLength (at offset 6 of struct usb_cdc_notification)  0B 0D 00 79    strh w11, [x8, #6]  // word (32-bit) store presumably to req-&gt;Length (at offset 8 of struct usb_request)  6C 0A 00 B9    str  w12, [x19, #8]  // x10 (NULL) was read here from offset 0 of valid pointer x9  // IMHO we&#39;re reading &#39;cdev-&gt;gadget&#39; and getting NULL  // gadget is indeed at offset 0 of struct usb_composite_dev  2A 01 40 F9    ldr  x10, [x9]  // loading req-&gt;buf pointer, which is at offset 0 of struct usb_request  69 02 40 F9    ldr  x9, [x19]  // x10 is null, crash, appears to be attempt to read cdev-&gt;gadget-&gt;max_speed  4B 5D 40 B9    ldr  w11, [x10, #0x5c]which seems to line up with ncm_do_notify() case NCM_NOTIFY_SPEED code fragment:  event-&gt;wLength = cpu_to_le16(8);  req-&gt;length = NCM_STATUS_BYTECOUNT;  /* SPEED_CHANGE data is up/down speeds in bits/sec */  data = req-&gt;buf + sizeof *event;  data[0] = cpu_to_le32(ncm_bitrate(cdev-&gt;gadget));My analysis of registers and NULL ptr deref crash offset  (Unable to handle kernel NULL pointer dereference at virtual address 000000000000005c)heavily suggests that the crash is due to &#39;cdev-&gt;gadget&#39; being NULL when executing:  data[0] = cpu_to_le32(ncm_bitrate(cdev-&gt;gadget));which calls:  ncm_bitrate(NULL)which then calls:  gadget_is_superspeed(NULL)which reads  ((struct usb_gadget *)NULL)-&gt;max_speedand hits a panic.AFAICT, if I&#39;m counting right, the offset of max_speed is indeed 0x5C.(remember there&#39;s a GKI KABI reservation of 16 bytes in struct work_struct)It&#39;s not at all clear to me how this is all supposed to work...but returning 0 seems much better than panic-ing...The Linux kernel CVE team has assigned CVE-2023-52894 to this issue.|
|已分析|2.openEulerScore|3.9|
|已分析|3.openEulerVector|AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L|
|已分析|4.受影响版本排查|openEuler-20.03-LTS-SP4:不受影响,openEuler-22.03-LTS-SP1:不受影响,openEuler-22.03-LTS-SP3:不受影响,openEuler-22.03-LTS-SP4:不受影响,master:不受影响,openEuler-24.03-LTS:不受影响,openEuler-24.03-LTS-Next:不受影响|
|已分析|5.修复是否涉及abi变化|openEuler-20.03-LTS-SP4:否,openEuler-22.03-LTS-SP1:否,openEuler-22.03-LTS-SP3:否,master:否,openEuler-24.03-LTS:否,openEuler-24.03-LTS-Next:否,openEuler-22.03-LTS-SP4:否|

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