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cat_backtrace() uses open_memstream() to build a backtrace string. When an invalid callchain context is encountered, zfree(&p) frees the memstream buffer, then the exit path calls fclose(f), which flushes to the already-freed buffer — a use-after-free. The function then returns a dangling pointer that the caller passes to a handler and subsequently double-frees. Fix by replacing the zfree(&p) with a 'corrupted' flag. At the exit label, always fclose(f) first (which finalizes the buffer), then conditionally free it when corrupted. This ensures the memstream contract is honored: the buffer remains valid until fclose(). While here, update the machine__resolve failure message to include file_offset and the event type name, matching the pattern from the preceding series. Also update the three legacy power event handlers under SUPPORT_OLD_POWER_EVENTS to include file_offset in their out-of-bounds CPU messages for consistency. Reported-by: sashiko-bot@kernel.org # Running on a local machine Reviewed-by: Ian Rogers <irogers@google.com> Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2090 lines
50 KiB
2090 lines
50 KiB