Bug 2516858 (CVE-2026-74403)

Summary: CVE-2026-74403 kernel: crypto: ccp - Check for page allocation failure correctly in TIO
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 Cryptographic Co-processor (CCP) driver. Under memory pressure, if a page allocation fails, the driver incorrectly processes the allocation result. This can lead to the dereferencing of an invalid memory address, potentially causing a system crash or other unpredictable behavior.
 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 06:37:10 UTC 
In the Linux kernel, the following vulnerability has been resolved:

crypto: ccp - Check for page allocation failure correctly in TIO

Sashiko notes:

> if __snp_alloc_firmware_pages() returns NULL under memory pressure, is it
> safe to pass it directly to page_address()?
>
> On architectures without HASHED_PAGE_VIRTUAL, page_address(NULL) might
> compute a deterministic but invalid, non-zero virtual address. The
> subsequent if (tio_status) check would then evaluate to true, and
> sev_tsm_init_locked() would dereference the invalid pointer.

Indeed, page_address(NULL) will return non-NULL garbage here. Fix this by
checking the page allocation itself for NULL, not the resulting virtual
address.
Comment 1 gkamathe 2026-08-19 12:43:27 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081509-CVE-2026-74403-03bc@gregkh/T