Re: [PATCH v1 1/2] perf maps: Avoid RC_CHK use after free

[Namhyung Kim]

On Tue, 18 Nov 2025 21:05:54 -0800, Ian Rogers wrote:
> The case of __maps__fixup_overlap_and_insert where the "new" maps
> covers existing mappings can create a use-after-free with reference
> count checking enabled. The issue is that "pos" holds a map pointer
> from maps_by_address that is put from maps_by_address but then used to
> look for a map in maps_by_name (the compared map is now a
> use-after-free). The issue stems from using maps__remove which redoes
> some of the searches already done by __maps__fixup_overlap_and_insert,
> so optimize the code (by avoiding repeated searches) and avoid the
> use-after-free by inlining the appropriate removal code.
> 
> [...]
Applied to perf-tools-next, thanks!

Best regards,
Namhyung