Re: [PATCH ndctl 1/4] ndctl/lib: fix usage of a non NUL-terminated string

[Alison Schofield <alison.schofield@intel.com>]

On Tue, Jan 10, 2023 at 04:09:14PM -0700, Vishal Verma wrote:
> Static analysis reports that in add_region(), a buffer from pread()
> won't have NUL-termination. Hence passing it to strtol subsequently can
> be wrong. Manually add the termination after pread() to fix this.
> 
> Fixes: c64cc150a21e ("ndctl: add support in libndctl to provide deep flush")
> Cc: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
> ---
>  ndctl/lib/libndctl.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/ndctl/lib/libndctl.c b/ndctl/lib/libndctl.c
> index f32f704..ddbdd9a 100644
> --- a/ndctl/lib/libndctl.c
> +++ b/ndctl/lib/libndctl.c
> @@ -2750,6 +2750,8 @@ static void *add_region(void *parent, int id, const char *region_base)
>  		goto out;
>  	}
>  
> +	/* pread() doesn't add NUL termination */
> +	buf[1] = 0;
>  	perm = strtol(buf, NULL, 0);
>  	if (perm == 0) {
>  		close(region->flush_fd);
> 

This diff is annoying because it didn't include enough to show the
pread().  Made me open up file ;)

Reviewed-by: Alison Schofield <alison.schofield@intel.com>


> -- 
> 2.39.0
>