Linux CVE-2026-23260

The vulnerability resides in the regmap (register map) subsystem of the Linux kernel, specifically in the maple tree-based register cache implementation (regcache_maple_write function). The regmap framework provides an abstraction layer for hardware register access, with caching mechanisms to optimize I/O operations. The maple tree is a modern data structure used for efficient range management in the kernel. When regcache_maple_write() attempts to merge adjacent register ranges, it allocates a new memory block ('entry') and attempts to store it using mas_store_gfp(). The root cause is improper error handling (CWE-401: Missing Release of Memory After Effective Lifetime) where the newly allocated entry is not freed when mas_store_gfp() fails, while the code correctly frees previously replaced neighbor blocks ('lower' and 'upper') on the success path. This affects the Linux kernel across all versions implementing this vulnerable pattern, as identified by CPE cpe:2.3:a:linux:linux:*:*:*:*:*:*:*:*.