[PATCH] ubiformat: get buffer from malloc

[Alexander Aring]

Hi,

On Mon, Mar 25, 2013 at 04:15:57PM +0100, Jan Weitzel wrote:
> There was a erase block sized (here 131072) char buf array on the stack.
> Changed this to get the space from malloc preventing stack overflows.
> Also fix a wrong return without clean up.
> 
> Signed-off-by: Jan Weitzel <j.weitzel at phytec.de>
> ---
>  commands/ubiformat.c |   22 +++++++++++++++-------
>  1 files changed, 15 insertions(+), 7 deletions(-)
> 
> diff --git a/commands/ubiformat.c b/commands/ubiformat.c
> index 47941be..121816f 100644
> --- a/commands/ubiformat.c
> +++ b/commands/ubiformat.c
> @@ -296,13 +296,20 @@ static int mark_bad(const struct mtd_dev_info *mtd, struct ubi_scan_info *si, in
>  static int flash_image(const struct mtd_dev_info *mtd,
>  		       const struct ubigen_info *ui, struct ubi_scan_info *si)
>  {
> -	int fd, img_ebs, eb, written_ebs = 0, divisor;
> +	int fd, img_ebs, eb, written_ebs = 0, divisor, ret = -1;
>  	off_t st_size;
> +	char *buf = NULL;
>  
>  	fd = open_file(&st_size);
>  	if (fd < 0)
>  		return fd;
>  
> +	buf = malloc(mtd->eb_size);
> +	if (!buf) {
> +		sys_errmsg("cannot allocate %d bytes of memory", mtd->eb_size);
> +		goto out_close;

meep, out_close will call free(buf). You need to add a new label above
free(buf);

> +	}
> +
>  	img_ebs = st_size / mtd->eb_size;
>  
>  	if (img_ebs > si->good_cnt) {
> @@ -312,8 +319,9 @@ static int flash_image(const struct mtd_dev_info *mtd,
>  	}
>  
>  	if (st_size % mtd->eb_size) {
> -		return sys_errmsg("file \"%s\" (size %lld bytes) is not multiple of ""eraseblock size (%d bytes)",
> -				  args.image, (long long)st_size, mtd->eb_size);
> +		sys_errmsg("file \"%s\" (size %lld bytes) is not multiple of "
> +			   "eraseblock size (%d bytes)",
> +			   args.image, (long long)st_size, mtd->eb_size);
>  		goto out_close;
>  	}
>  
> @@ -321,7 +329,6 @@ static int flash_image(const struct mtd_dev_info *mtd,
>  	divisor = img_ebs;
>  	for (eb = 0; eb < mtd->eb_cnt; eb++) {
>  		int err, new_len;
> -		char buf[mtd->eb_size];
>  		long long ec;
>  
>  		if (!args.quiet && !args.verbose) {
> @@ -404,12 +411,13 @@ static int flash_image(const struct mtd_dev_info *mtd,
>  
>  	if (!args.quiet && !args.verbose)
>  		printf("\n");
> -	close(fd);
> -	return eb + 1;
> +
> +	ret = eb + 1;
>  
>  out_close:
> +	free(buf);
here!
>  	close(fd);
> -	return -1;
> +	return ret;
>  }
>  
>  static int format(const struct mtd_dev_info *mtd,
> -- 
> 1.7.0.4
> 
> 

Alex