fuse-uring: fix moving cancelled entry to ent_in_userspace list
Published Jul 25, 2026
5.5
MEDIUMCVSS 3.1
EPSS 0.16%
Description
fuse_uring_cancel() moves entries that are available (these have no reqs attached) to the ent_in_userspace list. ent_list_request_expired() checks the first entry on ent_in_userspace and dereferences ent->fuse_req unconditionally, which will crash on a cancelled entry that was moved to this list.
Fix this by freeing the entry and dropping queue_refs directly in fuse_uring_cancel(). This is safe because cancel is the cancel handler itself - after io_uring_cmd_done(), no more cancels will be dispatched for this command, and teardown serializes with cancel via queue->lock.
Since cancel now decrements queue_refs, fuse_uring_abort() must no longer gate fuse_uring_abort_end_requests() on queue_refs > 0, as cancelled entries may have already dropped queue_refs while requests are still queued. Remove the gate so abort always flushes requests and stops queues.
Affected products
-
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version
-
- Version 6.16StatusaffectedConstraints-
- Version 0StatusunaffectedConstraints<6.16
- Version 6.18.39StatusunaffectedConstraints<=6.18.*
- Version 7.1.4StatusunaffectedConstraints<=7.1.*
- Version 7.2StatusunaffectedConstraints<=*
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
- ≥ 6.16 · < 6.18.39
- ≥ 6.19 · < 7.1.4
No data.
Red Hat Enterprise Linux 10
kernel
Not affected
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-rt
Not affected
Red Hat Enterprise Linux 8
kernel
Not affected
Red Hat Enterprise Linux 8
kernel-rt
Not affected
Red Hat Enterprise Linux 9
kernel
Not affected
Red Hat Enterprise Linux 9
kernel-rt
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise Linux 8 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 8 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise Linux 9 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 9 | kernel-rt | Not affected | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
References (9)
- https://access.redhat.com/security/cve/CVE-2026-64263 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2507179 Issue Tracking
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-48975 Advisory
- https://git.kernel.org/stable/c/198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc Patch
- https://git.kernel.org/stable/c/50f3e03db823cabc41fe35c27d77c2bdb112baad Patch
- https://git.kernel.org/stable/c/e8afc85acdf329361b2d8df2ad9b52364686235f Patch
- https://lore.kernel.org/linux-cve-announce/2026072558-CVE-2026-64263-971f@gregkh/T
- https://nvd.nist.gov/vuln/detail/CVE-2026-64263
- https://www.cve.org/CVERecord?id=CVE-2026-64263
Change history (0)
No recorded changes yet.