Linux Kernel up to 6.0.9 File Descriptor p9_fd_close file descriptor consumption

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5.3	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.0.9. It has been rated as critical. This issue affects the function p9_fd_close of the component File Descriptor Handler. Performing a manipulation results in file descriptor consumption. This vulnerability is known as CVE-2022-49767. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.0.9. It has been classified as critical. This affects the function p9_fd_close of the component File Descriptor Handler. The manipulation with an unknown input leads to a file descriptor consumption vulnerability. CWE is classifying the issue as CWE-769. This entry has been deprecated because it was a duplicate of CWE-774. All content has been transferred to CWE-774. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: 9p/trans_fd: always use O_NONBLOCK read/write syzbot is reporting hung task at p9_fd_close() [1], for p9_mux_poll_stop() from p9_conn_destroy() from p9_fd_close() is failing to interrupt already started kernel_read() from p9_fd_read() from p9_read_work() and/or kernel_write() from p9_fd_write() from p9_write_work() requests. Since p9_socket_open() sets O_NONBLOCK flag, p9_mux_poll_stop() does not need to interrupt kernel_read()/kernel_write(). However, since p9_fd_open() does not set O_NONBLOCK flag, but pipe blocks unless signal is pending, p9_mux_poll_stop() needs to interrupt kernel_read()/kernel_write() when the file descriptor refers to a pipe. In other words, pipe file descriptor needs to be handled as if socket file descriptor. We somehow need to interrupt kernel_read()/kernel_write() on pipes. A minimal change, which this patch is doing, is to set O_NONBLOCK flag from p9_fd_open(), for O_NONBLOCK flag does not affect reading/writing of regular files. But this approach changes O_NONBLOCK flag on userspace- supplied file descriptors (which might break userspace programs), and O_NONBLOCK flag could be changed by userspace. It would be possible to set O_NONBLOCK flag every time p9_fd_read()/p9_fd_write() is invoked, but still remains small race window for clearing O_NONBLOCK flag. If we don't want to manipulate O_NONBLOCK flag, we might be able to surround kernel_read()/kernel_write() with set_thread_flag(TIF_SIGPENDING) and recalc_sigpending(). Since p9_read_work()/p9_write_work() works are processed by kernel threads which process global system_wq workqueue, signals could not be delivered from remote threads when p9_mux_poll_stop() from p9_conn_destroy() from p9_fd_close() is called. Therefore, calling set_thread_flag(TIF_SIGPENDING)/recalc_sigpending() every time would be needed if we count on signals for making kernel_read()/kernel_write() non-blocking. [Dominique: add comment at Christian's suggestion]

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2022-49767 since 04/16/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 237098 (SUSE SLES15 Security Update : kernel (SUSE-SU-2025:01620-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.9.334, 4.14.300, 4.19.267, 5.4.225, 5.10.156, 5.15.80 or 6.0.10 eliminates this vulnerability. Applying the patch 0b5e6bd72b8171364616841603a70e4ba9837063/9f8554615df668e4bf83294633ee9d232b28ce45/7abf40f06a76c0dff42eada10597917e9776fbd4/b1ad04da7fe4515e2ce2d5f2dcab3b5b6d45614b/a8e2fc8f7b41fa9d9ca5f624f4e4d34fce5b40a9/0e07032b4b4724b8ad1003698cb81083c1818999/5af16182c5639349415118e9e9aecd8355f7a08b/ef575281b21e9a34dfae544a187c6aac2ae424a9 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (237098). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.9.333
• 4.14.299
• 4.19.266
• 5.4.224
• 5.10.155
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.15.61
• 5.15.62
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• 5.15.64
• 5.15.65
• 5.15.66
• 5.15.67
• 5.15.68
• 5.15.69
• 5.15.70
• 5.15.71
• 5.15.72
• 5.15.73
• 5.15.74
• 5.15.75
• 5.15.76
• 5.15.77
• 5.15.78
• 5.15.79
• 6.0.0
• 6.0.1
• 6.0.2
• 6.0.3
• 6.0.4
• 6.0.5
• 6.0.6
• 6.0.7
• 6.0.8
• 6.0.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: File descriptor consumption
CWE: CWE-769 / CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 237098
Nessus Name: SUSE SLES15 Security Update : kernel (SUSE-SU-2025:01620-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.9.334/4.14.300/4.19.267/5.4.225/5.10.156/5.15.80/6.0.10
Patch: 0b5e6bd72b8171364616841603a70e4ba9837063/9f8554615df668e4bf83294633ee9d232b28ce45/7abf40f06a76c0dff42eada10597917e9776fbd4/b1ad04da7fe4515e2ce2d5f2dcab3b5b6d45614b/a8e2fc8f7b41fa9d9ca5f624f4e4d34fce5b40a9/0e07032b4b4724b8ad1003698cb81083c1818999/5af16182c5639349415118e9e9aecd8355f7a08b/ef575281b21e9a34dfae544a187c6aac2ae424a9

Timelineinfo

04/16/2025 🔍
05/01/2025 +15 days 🔍
05/01/2025 +0 days 🔍
11/07/2025 +190 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2022-49767 (🔍)
GCVE (CVE): GCVE-0-2022-49767
GCVE (VulDB): GCVE-100-306915

Entryinfo

Created: 05/01/2025 17:18
Updated: 11/07/2025 13:14
Changes: 05/01/2025 17:18 (59), 05/23/2025 13:09 (2), 11/07/2025 13:14 (12)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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