Linux Kernel up to 6.6.54/6.10.13/6.11.2 on CSIPHY camss videobuf2-core.c stop_streaming reference count

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.6.54/6.10.13/6.11.2 on CSIPHY and classified as problematic. Impacted is the function stop_streaming of the file drivers/media/common/videobuf2/videobuf2-core.c of the component camss. The manipulation leads to reference count. This vulnerability is referenced as CVE-2024-50175. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 6.6.54/6.10.13/6.11.2 on CSIPHY. This issue affects the function stop_streaming of the file drivers/media/common/videobuf2/videobuf2-core.c of the component camss. The manipulation with an unknown input leads to a reference count vulnerability. Using CWE to declare the problem leads to CWE-911. The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: media: qcom: camss: Remove use_count guard in stop_streaming The use_count check was introduced so that multiple concurrent Raw Data Interfaces RDIs could be driven by different virtual channels VCs on the CSIPHY input driving the video pipeline. This is an invalid use of use_count though as use_count pertains to the number of times a video entity has been opened by user-space not the number of active streams. If use_count and stream-on count don't agree then stop_streaming() will break as is currently the case and has become apparent when using CAMSS with libcamera's released softisp 0.3. The use of use_count like this is a bit hacky and right now breaks regular usage of CAMSS for a single stream case. Stopping qcam results in the splat below, and then it cannot be started again and any attempts to do so fails with -EBUSY. [ 1265.509831] WARNING: CPU: 5 PID: 919 at drivers/media/common/videobuf2/videobuf2-core.c:2183 __vb2_queue_cancel+0x230/0x2c8 [videobuf2_common] ... [ 1265.510630] Call trace: [ 1265.510636] __vb2_queue_cancel+0x230/0x2c8 [videobuf2_common] [ 1265.510648] vb2_core_streamoff+0x24/0xcc [videobuf2_common] [ 1265.510660] vb2_ioctl_streamoff+0x5c/0xa8 [videobuf2_v4l2] [ 1265.510673] v4l_streamoff+0x24/0x30 [videodev] [ 1265.510707] __video_do_ioctl+0x190/0x3f4 [videodev] [ 1265.510732] video_usercopy+0x304/0x8c4 [videodev] [ 1265.510757] video_ioctl2+0x18/0x34 [videodev] [ 1265.510782] v4l2_ioctl+0x40/0x60 [videodev] ... [ 1265.510944] videobuf2_common: driver bug: stop_streaming operation is leaving buffer 0 in active state [ 1265.511175] videobuf2_common: driver bug: stop_streaming operation is leaving buffer 1 in active state [ 1265.511398] videobuf2_common: driver bug: stop_streaming operation is leaving buffer 2 in active st One CAMSS specific way to handle multiple VCs on the same RDI might be: - Reference count each pipeline enable for CSIPHY, CSID, VFE and RDIx. - The video buffers are already associated with msm_vfeN_rdiX so release video buffers when told to do so by stop_streaming. - Only release the power-domains for the CSIPHY, CSID and VFE when their internal refcounts drop. Either way refusing to release video buffers based on use_count is erroneous and should be reverted. The silicon enabling code for selecting VCs is perfectly fine. Its a "known missing feature" that concurrent VCs won't work with CAMSS right now. Initial testing with this code didn't show an error but, SoftISP and "real" usage with Google Hangouts breaks the upstream code pretty quickly, we need to do a partial revert and take another pass at VCs. This commit partially reverts commit 89013969e232 ("media: camss: sm8250: Pipeline starting and stopping for multiple virtual channels")

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2024-50175 since 10/21/2024. The exploitation is known to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 216760 (Ubuntu 22.04 LTS / 24.04 LTS : Linux kernel vulnerabilities (USN-7301-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.55, 6.10.14 or 6.11.3 eliminates this vulnerability. Applying the patch c2218a82f795/a975db8aea15/d7d4dde3dece/25f18cb1b673 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 (216760). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.10.0
• 6.10.1
• 6.10.2
• 6.10.3
• 6.10.4
• 6.10.5
• 6.10.6
• 6.10.7
• 6.10.8
• 6.10.9
• 6.10.10
• 6.10.11
• 6.10.12
• 6.10.13
• 6.11.0
• 6.11.1
• 6.11.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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

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