Bug 2536411 (CVE-2026-90295)

Summary: CVE-2026-90295 kernel: cpufreq: imx6q: fix out-of-bounds write when probed more than once
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the `cpufreq: imx6q` driver within the Linux kernel. When the driver is unbound and then rebound, a static counter is not reset, causing an out-of-bounds write to memory. A local attacker could exploit this vulnerability to trigger a kernel crash, leading to a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-17 17:45:02 UTC 
In the Linux kernel, the following vulnerability has been resolved:

cpufreq: imx6q: fix out-of-bounds write when probed more than once

imx6_soc_volt is allocated fresh on every probe, sized to the number of
ARM OPPs:

	imx6_soc_volt = devm_kcalloc(cpu_dev, num, sizeof(*imx6_soc_volt),
				     GFP_KERNEL);

but it is filled through soc_opp_count, which has static storage and is
never reset. A second bind after an unbind keeps indexing from where the
first one stopped, and writes past the end of the new array.

Unbinding and rebinding the driver on qemu's mcimx6ul-evk, under KASAN:

  BUG: KASAN: slab-out-of-bounds in imx6q_cpufreq_probe+0x3b0/0xa34
  Write of size 4 at addr c5e90480 by task binder/73
   imx6q_cpufreq_probe from platform_probe+0x88/0xe4
   platform_probe from really_probe+0x108/0x384
   bind_store from kernfs_fop_write_iter+0x1b4/0x28c

The write lands one u32 past the end of the allocation.

soc_opp_count is only read a few lines below the loop that fills it, so it
never needed static storage. Make it a local.
Comment 1 gkamathe 2026-09-22 19:59:13 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90295.mbox