Bug 2454806 (CVE-2026-23474)

Summary: CVE-2026-23474 kernel: mtd: Avoid boot crash in RedBoot partition table parser
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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OS: Linux   
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A flaw was found in the Linux kernel's Memory Technology Device (mtd) subsystem, specifically within the RedBoot partition table parser. A local user could trigger a buffer overflow when the system attempts to read beyond the allocated buffer size during partition table parsing. This vulnerability can lead to a system boot crash, resulting in a Denial of Service (DoS).
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Description OSIDB Bzimport 2026-04-03 16:01:43 UTC
In the Linux kernel, the following vulnerability has been resolved:

mtd: Avoid boot crash in RedBoot partition table parser

Given CONFIG_FORTIFY_SOURCE=y and a recent compiler,
commit 439a1bcac648 ("fortify: Use __builtin_dynamic_object_size() when
available") produces the warning below and an oops.

    Searching for RedBoot partition table in 50000000.flash at offset 0x7e0000
    ------------[ cut here ]------------
    WARNING: lib/string_helpers.c:1035 at 0xc029e04c, CPU#0: swapper/0/1
    memcmp: detected buffer overflow: 15 byte read of buffer size 14
    Modules linked in:
    CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.19.0 #1 NONE

As Kees said, "'names' is pointing to the final 'namelen' many bytes
of the allocation ... 'namelen' could be basically any length at all.
This fortify warning looks legit to me -- this code used to be reading
beyond the end of the allocation."

Since the size of the dynamic allocation is calculated with strlen()
we can use strcmp() instead of memcmp() and remain within bounds.