Executive brief
A vulnerability in the Linux kernel's Qualcomm graphics clock driver can cause the system to crash when attempting to adjust graphics performance. This issue occurs during routine power management tasks, such as when the system automatically scales GPU frequency to save power or improve performance. An exploit would result in a denial-of-service (system crash), impacting system availability and potentially causing data loss for unsaved work.
Technical details
A regression was introduced in the Linux kernel's Qualcomm GFX3D clock driver following the transition from round_rate() to determine_rate() in the clock divider framework. The clk_gfx3d_determine_rate function in drivers/clk/qcom/clk-rcg2.c failed to properly initialize the best_parent_hw field in the parent request structure. When __clk_determine_rate is subsequently called, the missing parent hardware reference leads to a kernel panic (crash). This is reachable via local power management or graphics frequency scaling operations (devfreq). The issue has been resolved by ensuring the parent request map correctly inherits the parent hardware reference from the primary request.
Affected products
- Linux Linux kernel v6.12 and later
Timeline
- 2026-01-17: other: Patch authored by Dmitry Baryshkov
- 2026-06-03: disclosed: CVE published by kernel.org
- 2026-06-03: patched: Fixes merged into stable branches
References
- https://git.kernel.org/stable/c/2583cb925ca1ce450aa5d74a05a67448db970193
- https://git.kernel.org/stable/c/547ae2f17349c7586953af5ef50de43ef3f65e9e
- https://git.kernel.org/stable/c/56360aa4ddd736fc19e6d0b0206c5e437e0d6ff8
- https://git.kernel.org/stable/c/82cfe5292b11deb1dc33822f67f73cfbe8eafe25
- https://git.kernel.org/stable/c/8aa972eba1f29068d13bec716d33abca30fb3f2a
- https://git.kernel.org/stable/c/aed53da569fb96eec09b4817b1953bcc2e467eea