drm/nouveau/clk: fix list cursor use after loop in nvkm_clk_ustate_update

Summary

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau/clk: fix list cursor use after loop in nvkm_clk_ustate_update If list_for_each_entry() exits without hitting a break then "pstate" is not a valid pstate pointer. Introduce a "found" variable instead. The check is reachable from userspace: nvkm_clk_ustate_update() takes the pstate id straight from the 'pstate' debugfs file, so requesting an id that is not in clk->states - or any id at all when the perf tables are broken and the list is empty - makes the pstate->pstate != req test dereference the list head cast to a struct nvkm_pstate, which is an out-of-bounds read. [Francesco: rebased on drm-misc-next, expanded the commit message]

Timeline

1. Oct 18, 2026, 3:19 PM UTCCVE published
2. Oct 19, 2026, 9:22 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in db5dd9f47b4df1be322f498d846e9a82940a7390; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in 9d550924961f61a491dd95359c63494fa8a23d9f; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in 492e9cfa12f35f7946ea1b78a19f1f9337d62248; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in a867abcfa85ab487066c3d3008a1ba905da04113; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in 5315c7bacfe274ddfe649d9556e9a341ffa812da; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in 0d096a7f7d79207490858dde731b16da5337e90c; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in 391517da7fd54ae40e4a7fe1cc696217343b0061; From 7c856522069755ab9d163a24ac332cd3cb35fe30 · fixed in aff09d9e37e02dc60bde79035ac15b136d602259

• Linux Linux

  3.13

• KernelLinux

  From 3.13.0 · fixed in 5.10.271; From 5.11.0 · fixed in 5.15.222; From 5.16.0 · fixed in 6.1.189; From 6.2.0 · fixed in 6.6.158; From 6.7.0 · fixed in 6.12.112; From 6.13.0 · fixed in 6.18.55; From 6.19.0 · fixed in 7.2.9

References 8