Re: [PATCH v3 02/16] tracing/filters: Fix MATCH_END_ONLY regex matching for fixed-size strings

From: Masami Hiramatsu (Google)

Date: Tue Oct 27 2026 - 21:18:14 EST


On Wed, 28 Oct 2026 09:43:43 +0900, Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> wrote:

> diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> --- a/kernel/trace/trace_events_filter.c
> +++ b/kernel/trace/trace_events_filter.c
> @@ -1087,6 +1087,20 @@ static int regex_match_end(char *str, struct regex *r, int len)
> +{
> + int slen;
> +
> + if (len < r->len)

BTW, this is required for skipping strnlen().

> + return 0;
> +
> + slen = strnlen(str, len);
> + if (slen >= r->len &&

And this also checks actual length.

> + memcmp(str + slen - r->len, r->pattern, r->len) == 0)
> + return 1;
> + return 0;

Thanks,

--
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>