Bug 2516744 (CVE-2026-74404)

Summary: CVE-2026-74404 kernel: crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's crypto: ccp component. An off-by-one error in the `snp_filter_reserved_mem_regions()` function can lead to a heap buffer overflow. This vulnerability could allow an attacker to corrupt memory, potentially leading to a denial of service or arbitrary code execution.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-08-15 06:31:18 UTC 
In the Linux kernel, the following vulnerability has been resolved:

crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one

Sashiko notes:

> regarding the bounds check in snp_filter_reserved_mem_regions()
> called via walk_iomem_res_desc(): does the check
> if ((range_list->num_elements * 16 + 8) > PAGE_SIZE)
> allow an off-by-one heap buffer overflow?
>
> If range_list->num_elements is 255, 255 * 16 + 8 = 4088, which is <= 4096.
> Writing range->base (8 bytes) fills 4088-4095, but writing range->page_count
> (4 bytes) would write to 4096-4099, overflowing the kzalloc-allocated
> PAGE_SIZE buffer.

Fix this by accounting for the entry about to be written to, in addition to
the entries that are already allocated.
Comment 1 Keith Grant 2026-08-20 21:05:54 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081509-CVE-2026-74404-2b54@gregkh/T