Bug 2467170 (CVE-2026-43124)

Summary: CVE-2026-43124 kernel: pstore: ram_core: fix incorrect success return when vmap() fails
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's pstore ram_core component. A local attacker could exploit a vulnerability where the `persistent_ram_buffer_map()` function incorrectly returns success even when the underlying `vmap()` memory mapping operation fails. This occurs if a non-zero offset is used, leading to attempts to access an invalid memory address. Successful exploitation of this flaw would result in a system crash, causing a Denial of Service (DoS).
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Description OSIDB Bzimport 2026-05-06 13:08:22 UTC 
In the Linux kernel, the following vulnerability has been resolved:

pstore: ram_core: fix incorrect success return when vmap() fails

In persistent_ram_vmap(), vmap() may return NULL on failure.

If offset is non-zero, adding offset_in_page(start) causes the function
to return a non-NULL pointer even though the mapping failed.
persistent_ram_buffer_map() therefore incorrectly returns success.

Subsequent access to prz->buffer may dereference an invalid address
and cause crashes.

Add proper NULL checking for vmap() failures.
Comment 1 Keith Grant 2026-05-06 17:37:46 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026050619-CVE-2026-43124-8141@gregkh/T