Memory Management Vulnerability in Linux Kernel Affecting Multiple Distributions

CVE-2026-80729

What is CVE-2026-80729?

A vulnerability in the Linux kernel's memory management system relates to the improper initialization of workingset states before folio splits. Specifically, the function xas_try_split() adds accounting for page-cache xa_nodes, however, __folio_split() fails to set the xa_state's xa_lru. This oversight permits a live, memory control group (memcg)-charged xa_node to exist without being linked to the corresponding mapping's shadow_nodes list_lru. Subsequently, when the reclaim process iterates through the list_lru, it triggers a warning due to the unexpected state of the control group. The issue has been corrected to ensure that both the workingset update callback and the shadow_nodes list_lru are appropriately initialized during the mapping set update process.

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