[PATCH v2] posix: Avoid a stack overflow when glob is given many trailing slashes [BZ #30635]

[Andreas Schwab]

On Okt 07 2025, Collin Funk wrote:

> diff --git a/posix/glob.c b/posix/glob.c
> index a7c7dd1ebe..82ee873d80 100644
> --- a/posix/glob.c
> +++ b/posix/glob.c
> @@ -596,6 +596,10 @@ __glob (const char *pattern, int flags, int (*errfunc) (const char *, int),
>                    flags &= ~(GLOB_NOCHECK | GLOB_NOMAGIC);
>                  }
>              }
> +          /* Prevent stack overflows with many trailing '/' characters.  */
> +          for (char *p = &dirname[dirlen - 1];
> +               dirname < p && p[0] == '/' && p[-1] == '/'; --p)
                  p > dirname

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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