Description

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...

Classification

CVE ID: CVE-2024-50175

CVSS Base Severity: MEDIUM

CVSS Base Score: 5.5

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.03% (probability of being exploited)

EPSS Percentile: 5.3% (scored less or equal to compared to others)

EPSS Date: 2025-06-02 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2024-50175
https://git.kernel.org/stable/c/c2218a82f795dc3d0b6210bcaa3d9c5ca736fcd9
https://git.kernel.org/stable/c/a975db8aea152f9907aa53a7f517e557ccb40da3
https://git.kernel.org/stable/c/d7d4dde3decef1b5aa1f5c390147f79aae412dee
https://git.kernel.org/stable/c/25f18cb1b673220b76a86ebef8e7fb79bd303b27

Timeline