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

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
> 

with fgets shows (count in example is buffer_size.
count: The maximum number of characters to read, including the 
null terminator (\0). fgets reads at most count - 1 characters into 
the buffer.

buffer_size = 2 * stat_buf.st_size + 4096;

So, don't know how close it is the size of line and the buffer?





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 Michael D. Setzer II - Computer Science Instructor (Retired)     
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