DEBIAN-CVE-2026-64034
In the Linux kernel, the following vulnerability has been resolved: net: mana: Fix TOCTOU double-fetch of hwcmsgid from DMA buffer In manahwcrxeventhandler(), resp->response.hwcmsgid is read from DMA-coherent memory and bounds-checked, then manahwchandleresp() re-reads the same field from the same DMA buffer for testbit() and pointer arithmetic. DMA-coherent memory is mapped uncacheable on x86 and is shared, unencrypted, in Confidential VMs (SEV-SNP/TDX), so each load goes directly to host-visible memory. A H/W can modify the value between the check and the use, bypassing the bounds validation. Fix this by reading hwcmsgid exactly once using READONCE() into a stack-local variable in manahwcrxeventhandler(), and passing the validated value as a parameter to manahwchandleresp().
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version



Related Resources
References
https://security-tracker.debian.org/tracker/CVE-2026-64034