Re: [PATCH] build system: fix potential buffer overflow

On Sun, 29 Mar 2026 at 17:52, Michael D. Setzer II via busybox
<[email protected]> wrote:
>
> On 29 Mar 2026 at 13:20, Alyssa Ross via busybox wrote:
>
> To:                     [email protected]
> Subject:                [PATCH] build system: fix potential buffer overflow
> Date sent:              Sun, 29 Mar 2026 13:20:36 +0200
> From:                   Alyssa Ross via busybox <[email protected]>
> Send reply to:          Alyssa Ross <[email protected]>
>
> > This could potentially write one byte past the end of line.
> > Identified by fortify-headers.
> > ---
> >  scripts/basic/split-include.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/scripts/basic/split-include.c b/scripts/basic/split-include.c
> > index 6ef29195e..93011d511 100644
> > --- a/scripts/basic/split-include.c
> > +++ b/scripts/basic/split-include.c
> > @@ -195,7 +195,7 @@ int main(int argc, const char * argv [])
> >       ERROR_EXIT( "find" );
> >
> >      line[0] = '\n';
> > -    while (fgets(line+1, buffer_size, fp_find))
> > +    while (fgets(line+1, buffer_size-1, fp_find))
> >      {
> >       if (strstr(list_target, line) == NULL)
> >       {
> > --
> > 2.53.0
> >
>
> Question: Looked at file and there are multiple fgets lines.
>
> cat -n split-include.c | grep fgets
>    105      while (fgets(line, buffer_size, fp_config))
>    134              if (!fgets(old_line, buffer_size, fp_target) &&
> ferror(fp_target))
>    189       * fgets gives the incoming names a terminating \n.
>    198      while (fgets(line+1, buffer_size, fp_find))
>
> 189 is part of a comment, but wouldn't fix also apply to other lines?
>

At the moment I am just importing what has been submitted as-is, then
evaluation will be provided later (cfr: Status in others commit). Feel
free to clone the repository and submit any changes by patch or even
better request of pull. Please keep the "bug fixes" branch as
reference (even better at your specific last patch commit as HEAD).

Best regards, R-