Bug 2535326 (CVE-2026-89976)

Summary: CVE-2026-89976 kernel: accel/ethosu: fix job completion fence cleanup
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 Linux kernel's accel/ethosu component. This vulnerability occurs due to improper handling of job completion fences, where an uninitialized fence can be leaked or a zeroed reference count is passed to the `dma_fence_put()` function. A local attacker could potentially exploit this flaw to cause a resource leak, leading to system instability or a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-16 12:04:14 UTC 
In the Linux kernel, the following vulnerability has been resolved:

accel/ethosu: fix job completion fence cleanup

ethosu_ioctl_submit_job() allocates done_fence before validating buffer
handles. Errors after allocation call ethosu_job_err_cleanup(), which frees
the job but leaks the uninitialized fence.

A scheduler dependency error also lets ethosu_job_run() return before
dma_fence_init(). Normal cleanup then passes a zeroed refcount to
dma_fence_put().

Release done_fence in the common cleanup path and use
dma_fence_was_initialized() to distinguish initialized fences from raw
allocations.

[robh: also fix goto]
Comment 1 gkamathe 2026-09-17 09:58:58 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89976.mbox