Bug 2507039 (CVE-2026-64260)

Summary: CVE-2026-64260 kernel: fuse-uring: Avoid queue->stopped races and set/read that value under lock
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: unspecifiedCC: rhel-process-autobot, 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 `fuse-uring` component of the Linux kernel. A race condition exists where the `queue->stopped` flag is not consistently checked under a lock. This can allow a `struct fuse_req` to be prematurely freed while other operations are still in progress, potentially leading to memory corruption. A local attacker could exploit this vulnerability to cause system instability or potentially escalate privileges.
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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 2026-07-25 10:01:49 UTC 
In the Linux kernel, the following vulnerability has been resolved:

fuse-uring: Avoid queue->stopped races and set/read that value under lock

There are several readers of queue->stopped that check the value
under lock, but fuse_uring_commit_fetch() did not and actually
the value was not set under the lock in fuse_uring_abort_end_requests()
either. Especially in fuse_uring_commit_fetch it is important
to check under a lock, because due to races 'struct fuse_req'
might be freed with fuse_request_end, but another thread/cpu
might already do teardown work.
Comment 1 Mauro Matteo Cascella 2026-07-28 16:20:58 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026072557-CVE-2026-64260-f7d4@gregkh/T