cd /sys/kernel/tracing

一、漏洞信息
漏洞编号：CVE-2023-52879
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:tracing: Have trace_event_file have ref countersThe following can crash the kernel: # cd /sys/kernel/tracing # echo p:sched schedule > kprobe_events # exec 5>>events/kprobes/sched/enable # > kprobe_events # exec 5>&-The above commands: 1. Change directory to the tracefs directory 2. Create a kprobe event (doesn t matter what one) 3. Open bash file descriptor 5 on the enable file of the kprobe event 4. Delete the kprobe event (removes the files too) 5. Close the bash file descriptor 5The above causes a crash! BUG: kernel NULL pointer dereference, address: 0000000000000028 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:tracing_release_file_tr+0xc/0x50What happens here is that the kprobe event creates a trace_event_file file descriptor that represents the file in tracefs to the event. Itmaintains state of the event (is it enabled for the given instance?).Opening the enable file gets a reference to the event file descriptorvia the open file descriptor. When the kprobe event is deleted, the file isalso deleted from the tracefs system which also frees the event file descriptor.But as the tracefs file is still opened by user space, it will not betotally removed until the final dput() is called on it. But this is nottrue with the event file descriptor that is already freed. If the userdoes a write to or simply closes the file descriptor it will reference theevent file descriptor that was just freed, causing a use-after-free bug.To solve this, add a ref count to the event file descriptor as well as anew flag called FREED . The file will not be freed until the lastreference is released. But the FREE flag will be set when the event isremoved to prevent any more modifications to that event from happening,even if there s still a reference to the event file descriptor.
漏洞公开时间：2024-05-22 00:15:24
漏洞创建时间：2024-05-23 00:44:11
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2023-52879

更多参考(点击展开)

参考来源	参考链接	来源链接
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2c9de867ca285c397cd71af703763fe416265706
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2fa74d29fc1899c237d51bf9a6e132ea5c488976
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/9034c87d61be8cff989017740a91701ac8195a1d
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/961c4511c7578d6b8f39118be919016ec3db1c1e
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a98172e36e5f1b3d29ad71fade2d611cfcc2fe6f
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/cbc7c29dff0fa18162f2a3889d82eeefd67305e0
suse_bugzilla	http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-52879	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2023/CVE-2023-52879.mbox	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/961c4511c7578d6b8f39118be919016ec3db1c1e	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/a98172e36e5f1b3d29ad71fade2d611cfcc2fe6f	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/cbc7c29dff0fa18162f2a3889d82eeefd67305e0	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/2fa74d29fc1899c237d51bf9a6e132ea5c488976	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/2c9de867ca285c397cd71af703763fe416265706	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/9034c87d61be8cff989017740a91701ac8195a1d	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://git.kernel.org/stable/c/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4	https://bugzilla.suse.com/show_bug.cgi?id=1225101
suse_bugzilla	https://www.cve.org/CVERecord?id=CVE-2023-52879	https://bugzilla.suse.com/show_bug.cgi?id=1225101
redhat_bugzilla	https://lore.kernel.org/linux-cve-announce/2024052122-CVE-2023-52879-fa4d@gregkh/T	https://bugzilla.redhat.com/show_bug.cgi?id=2282730
ubuntu	https://www.cve.org/CVERecord?id=CVE-2023-52879	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/linus/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4 (6.7-rc1)	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/961c4511c7578d6b8f39118be919016ec3db1c1e	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/a98172e36e5f1b3d29ad71fade2d611cfcc2fe6f	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/cbc7c29dff0fa18162f2a3889d82eeefd67305e0	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/2fa74d29fc1899c237d51bf9a6e132ea5c488976	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/2c9de867ca285c397cd71af703763fe416265706	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/9034c87d61be8cff989017740a91701ac8195a1d	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://git.kernel.org/stable/c/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://nvd.nist.gov/vuln/detail/CVE-2023-52879	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://launchpad.net/bugs/cve/CVE-2023-52879	https://ubuntu.com/security/CVE-2023-52879
ubuntu	https://security-tracker.debian.org/tracker/CVE-2023-52879	https://ubuntu.com/security/CVE-2023-52879
debian		https://security-tracker.debian.org/tracker/CVE-2023-52879

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：

详情(点击展开)

影响的包	修复版本	修复补丁	问题引入补丁	来源
linux		https://git.kernel.org/linus/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4	https://git.kernel.org/linus/f5ca233e2e66dc1c249bf07eefa37e34a6c9346a	ubuntu
linux		https://git.kernel.org/linus/9034c87d61be8cff989017740a91701ac8195a1d	https://git.kernel.org/linus/f5ca233e2e66dc1c249bf07eefa37e34a6c9346a	ubuntu

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:tracing: Have trace_event_file have ref countersThe following can crash the kernel: # cd /sys/kernel/tracing # echo p:sched schedule > kprobe_events # exec 5>>events/kprobes/sched/enable # > kprobe_events # exec 5>&-The above commands: 1. Change directory to the tracefs directory 2. Create a kprobe event (doesn t matter what one) 3. Open bash file descriptor 5 on the enable file of the kprobe event 4. Delete the kprobe event (removes the files too) 5. Close the bash file descriptor 5The above causes a crash! BUG: kernel NULL pointer dereference, address: 0000000000000028 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:tracing_release_file_tr+0xc/0x50What happens here is that the kprobe event creates a trace_event_file file descriptor that represents the file in tracefs to the event. Itmaintains state of the event (is it enabled for the given instance?).Opening the enable file gets a reference to the event file descriptorvia the open file descriptor. When the kprobe event is deleted, the file isalso deleted from the tracefs system which also frees the event file descriptor.But as the tracefs file is still opened by user space, it will not betotally removed until the final dput() is called on it. But this is nottrue with the event file descriptor that is already freed. If the userdoes a write to or simply closes the file descriptor it will reference theevent file descriptor that was just freed, causing a use-after-free bug.To solve this, add a ref count to the event file descriptor as well as anew flag called FREED . The file will not be freed until the lastreference is released. But the FREE flag will be set when the event isremoved to prevent any more modifications to that event from happening,even if there s still a reference to the event file descriptor.
openEuler评分：
4.4
Vector：CVSS：3.0/AV:L/AC:L/PR:H/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-22.03-LTS-SP1(5.10.0):受影响
2.openEuler-22.03-LTS-SP3(5.10.0):受影响
3.openEuler-22.03-LTS-SP4(5.10.0):受影响
4.openEuler-20.03-LTS-SP4(4.19.90):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

Hi openeuler-ci-bot, welcome to the openEuler Community.
I'm the Bot here serving you. You can find the instructions on how to interact with me at Here.
If you have any questions, please contact the SIG: Kernel, and any of the maintainers.

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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-SP1(4.19.90):
3.openEuler-20.03-LTS-SP4(4.19.90):
4.openEuler-22.03-LTS(5.10.0):
5.openEuler-22.03-LTS-Next(5.10.0):
6.openEuler-22.03-LTS-SP1(5.10.0):
7.openEuler-22.03-LTS-SP2(5.10.0):
8.openEuler-22.03-LTS-SP3(5.10.0):
9.openEuler-22.03-LTS-SP4:
10.openEuler-24.03-LTS:
11.openEuler-24.03-LTS-Next:

修复是否涉及abi变化(是/否)：
1.master(6.1.0):
2.openEuler-20.03-LTS-SP1(4.19.90):
3.openEuler-20.03-LTS-SP4(4.19.90):
4.openEuler-22.03-LTS(5.10.0):
5.openEuler-22.03-LTS-Next(5.10.0):
6.openEuler-22.03-LTS-SP1(5.10.0):
7.openEuler-22.03-LTS-SP2(5.10.0):
8.openEuler-22.03-LTS-SP3(5.10.0):
9.openEuler-22.03-LTS-SP4:
10.openEuler-24.03-LTS:
11.openEuler-24.03-LTS-Next:

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-2023-52879	None	None	https://git.kernel.org/stable/c/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4 https://git.kernel.org/stable/c/9034c87d61be8cff989017740a91701ac8195a1d https://git.kernel.org/stable/c/a98172e36e5f1b3d29ad71fade2d611cfcc2fe6f https://git.kernel.org/stable/c/2fa74d29fc1899c237d51bf9a6e132ea5c488976 https://git.kernel.org/stable/c/2c9de867ca285c397cd71af703763fe416265706 https://git.kernel.org/stable/c/cbc7c29dff0fa18162f2a3889d82eeefd67305e0 https://git.kernel.org/stable/c/961c4511c7578d6b8f39118be919016ec3db1c1e
https://www.opencve.io/cve/CVE-2023-52879	None	None	https://git.kernel.org/stable/c/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4 https://git.kernel.org/stable/c/9034c87d61be8cff989017740a91701ac8195a1d https://git.kernel.org/stable/c/a98172e36e5f1b3d29ad71fade2d611cfcc2fe6f https://git.kernel.org/stable/c/2fa74d29fc1899c237d51bf9a6e132ea5c488976 https://git.kernel.org/stable/c/2c9de867ca285c397cd71af703763fe416265706 https://git.kernel.org/stable/c/cbc7c29dff0fa18162f2a3889d82eeefd67305e0 https://git.kernel.org/stable/c/961c4511c7578d6b8f39118be919016ec3db1c1e
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2023-52879
https://security-tracker.debian.org/tracker/CVE-2023-52879	None	None	https://git.kernel.org/linus/bb32500fb9b78215e4ef6ee8b4345c5f5d7eafb4

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-2023-52879

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

tracing: Have trace_event_file have ref counters

The following can crash the kernel:

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

The above commands:

Change directory to the tracefs directory
Create a kprobe event (doesn't matter what one)
Open bash file descriptor 5 on the enable file of the kprobe event
Delete the kprobe event (removes the files too)
Close the bash file descriptor 5

The above causes a crash!

BUG: kernel NULL pointer dereference, address: 0000000000000028
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:tracing_release_file_tr+0xc/0x50

What happens here is that the kprobe event creates a trace_event_file
"file" descriptor that represents the file in tracefs to the event. It
maintains state of the event (is it enabled for the given instance?).
Opening the "enable" file gets a reference to the event "file" descriptor
via the open file descriptor. When the kprobe event is deleted, the file is
also deleted from the tracefs system which also frees the event "file"
descriptor.

But as the tracefs file is still opened by user space, it will not be
totally removed until the final dput() is called on it. But this is not
true with the event "file" descriptor that is already freed. If the user
does a write to or simply closes the file descriptor it will reference the
event "file" descriptor that was just freed, causing a use-after-free bug.

To solve this, add a ref count to the event "file" descriptor as well as a
new flag called "FREED". The "file" will not be freed until the last
reference is released. But the FREE flag will be set when the event is
removed to prevent any more modifications to that event from happening,
even if there's still a reference to the event "file" descriptor.

openEuler评分:(评分和向量)
0
CVSS: 3.0/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:N

受影响版本排查(受影响/不受影响):
1.openEuler-20.03-LTS-SP1:不受影响
2.openEuler-20.03-LTS-SP4:不受影响
3.openEuler-22.03-LTS:受影响
4.openEuler-22.03-LTS-SP1:受影响
5.openEuler-22.03-LTS-SP2:受影响
6.openEuler-22.03-LTS-SP3:受影响
7.master(6.1.0):不受影响
8.openEuler-22.03-LTS-Next:不受影响
9.openEuler-24.03-LTS:不受影响
10.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-SP1(4.19.90):否
2.openEuler-20.03-LTS-SP4:否
3.openEuler-22.03-LTS:否
4.openEuler-22.03-LTS-SP1:否
5.openEuler-22.03-LTS-SP2:否
6.openEuler-22.03-LTS-SP3:否
7.master(6.1.0):否
8.openEuler-22.03-LTS-Next:否
9.openEuler-24.03-LTS:否
10.openEuler-24.03-LTS-Next:否

@zhixiuzhou 2.openEulerScore=> 没有填写或正确填写(0-10)

@guo-mengqi 请确认分支: openEuler-22.03-LTS-SP4 受影响/不受影响.
请确认分支信息是否填写完整,否则将无法关闭当前issue.

CVE-2023-52879

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

tracing: Have trace_event_file have ref counters

The following can crash the kernel:

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

The above commands:

Change directory to the tracefs directory
Create a kprobe event (doesn't matter what one)
Open bash file descriptor 5 on the enable file of the kprobe event
Delete the kprobe event (removes the files too)
Close the bash file descriptor 5

The above causes a crash!

BUG: kernel NULL pointer dereference, address: 0000000000000028
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:tracing_release_file_tr+0xc/0x50

What happens here is that the kprobe event creates a trace_event_file
"file" descriptor that represents the file in tracefs to the event. It
maintains state of the event (is it enabled for the given instance?).
Opening the "enable" file gets a reference to the event "file" descriptor
via the open file descriptor. When the kprobe event is deleted, the file is
also deleted from the tracefs system which also frees the event "file"
descriptor.

But as the tracefs file is still opened by user space, it will not be
totally removed until the final dput() is called on it. But this is not
true with the event "file" descriptor that is already freed. If the user
does a write to or simply closes the file descriptor it will reference the
event "file" descriptor that was just freed, causing a use-after-free bug.

To solve this, add a ref count to the event "file" descriptor as well as a
new flag called "FREED". The "file" will not be freed until the last
reference is released. But the FREE flag will be set when the event is
removed to prevent any more modifications to that event from happening,
even if there's still a reference to the event "file" descriptor.

openEuler评分:(评分和向量)
4.4
CVSS:3.1/AV:L/AC:L/PR:H/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:不受影响
2.openEuler-22.03-LTS-SP1:受影响
3.openEuler-22.03-LTS-SP3:受影响
4.openEuler-22.03-LTS-SP4: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

===========================================================

CVE-2023-52879

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

tracing: Have trace_event_file have ref counters

The following can crash the kernel:

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

The above commands:

Change directory to the tracefs directory
Create a kprobe event (doesn't matter what one)
Open bash file descriptor 5 on the enable file of the kprobe event
Delete the kprobe event (removes the files too)
Close the bash file descriptor 5

The above causes a crash!

BUG: kernel NULL pointer dereference, address: 0000000000000028
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:tracing_release_file_tr+0xc/0x50

What happens here is that the kprobe event creates a trace_event_file
"file" descriptor that represents the file in tracefs to the event. It
maintains state of the event (is it enabled for the given instance?).
Opening the "enable" file gets a reference to the event "file" descriptor
via the open file descriptor. When the kprobe event is deleted, the file is
also deleted from the tracefs system which also frees the event "file"
descriptor.

But as the tracefs file is still opened by user space, it will not be
totally removed until the final dput() is called on it. But this is not
true with the event "file" descriptor that is already freed. If the user
does a write to or simply closes the file descriptor it will reference the
event "file" descriptor that was just freed, causing a use-after-free bug.

To solve this, add a ref count to the event "file" descriptor as well as a
new flag called "FREED". The "file" will not be freed until the last
reference is released. But the FREE flag will be set when the event is
removed to prevent any more modifications to that event from happening,
even if there's still a reference to the event "file" descriptor.

openEuler评分:(评分和向量)
4.4
CVSS:3.1/AV:L/AC:L/PR:H/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:不受影响
2.openEuler-22.03-LTS-SP1:受影响
3.openEuler-22.03-LTS-SP3:受影响
4.openEuler-22.03-LTS-SP4: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

===========================================================

@sanglipeng 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:tracing: Have trace_event_file have ref countersThe following can crash the kernel: # cd /sys/kernel/tracing # echo 'p:sched schedule' > kprobe_events # exec 5>>events/kprobes/sched/enable # > kprobe_events # exec 5>&-The above commands: 1. Change directory to the tracefs directory 2. Create a kprobe event (doesn't matter what one) 3. Open bash file descriptor 5 on the enable file of the kprobe event 4. Delete the kprobe event (removes the files too) 5. Close the bash file descriptor 5The above causes a crash! BUG: kernel NULL pointer dereference, address: 0000000000000028 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:tracing_release_file_tr+0xc/0x50What happens here is that the kprobe event creates a trace_event_file"file" descriptor that represents the file in tracefs to the event. Itmaintains state of the event (is it enabled for the given instance?).Opening the "enable" file gets a reference to the event "file" descriptorvia the open file descriptor. When the kprobe event is deleted, the file isalso deleted from the tracefs system which also frees the event "file"descriptor.But as the tracefs file is still opened by user space, it will not betotally removed until the final dput() is called on it. But this is nottrue with the event "file" descriptor that is already freed. If the userdoes a write to or simply closes the file descriptor it will reference theevent "file" descriptor that was just freed, causing a use-after-free bug.To solve this, add a ref count to the event "file" descriptor as well as anew flag called "FREED". The "file" will not be freed until the lastreference is released. But the FREE flag will be set when the event isremoved to prevent any more modifications to that event from happening,even if there's still a reference to the event "file" descriptor.
已分析	2.openEulerScore	4.4
已分析	3.openEulerVector	AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
已分析	4.受影响版本排查	openEuler-22.03-LTS-SP1:受影响,openEuler-22.03-LTS-SP3:受影响,openEuler-22.03-LTS-SP4:受影响,openEuler-20.03-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

请确认分析内容的准确性, 确认无误后, 您可以进行后续步骤, 否则您可以继续分析.

@gatieme ,@xiexiuqi ,@yangyingliang ,@pi3orama ,@jiaoff ,@guo-mengqi
关闭issue前,需要将受影响的分支在合并pr时关联上当前issue编号: #I9RG0I
受影响分支: openEuler-22.03-LTS-SP4
具体操作参考: https://gitee.com/help/articles/4142

src-openEuler/kernel

内容风险标识

CVE-2023-52879

评论 (52)

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

src-openEuler/kernel .gitee-modal { width: 500px !important; }

内容风险标识

CVE-2023-52879

评论 (52)

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

cd /sys/kernel/tracing

echo 'p:sched schedule' > kprobe_events

exec 5>>events/kprobes/sched/enable

> kprobe_events

exec 5>&-

搜索帮助

src-openEuler/kernel