CVE-2025-38517 lib/alloc_tag: do not acquire non-existent lock in alloc_tag_top_users()

In the Linux kernel, the following vulnerability has been resolved: lib/alloctag: do not acquire non-existent lock in alloctagtopusers alloctagtopusers attempts to lock alloctagcttype-modlock even when the alloctagcttype is not allocated because: 1 alloc tagging is disabled because mem profiling ...

CVE-2025-38517

CVE-2025-38517 is a Linux kernel issue in lib/alloc_tag where alloc_tag_top_users() may lock alloc_tag_cttype->mod_lock even when alloc_tag_cttype is NULL or invalid, leading to a crash on memory allocation failure. The root cause is that alloc_tag_cttype can be NULL or an error value in scena...