Re: [PATCH] tools/mxsimage: Remove fclose on empty FILE pointer

[Wolfgang Denk]

Dear Mattias Hansson,

In message <20211123080633.8318-1-hansson.matt...@gmail.com> you wrote:
> If `sb_load_cmdfile()` fails to open the configuration file it will jump
> to error handling where the code will try to `fclose()` the FILE pointer
> which is NULL causing `mkimage` to segfault.
>
> This patch removes the `fclose()` since `fopen()` always returns NULL
> instead of the file descriptor when failing.
> ---
>  tools/mxsimage.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/tools/mxsimage.c b/tools/mxsimage.c
> index 002f4b525a..c7bd86ce52 100644
> --- a/tools/mxsimage.c
> +++ b/tools/mxsimage.c
> @@ -1618,7 +1618,6 @@ static int sb_load_cmdfile(struct sb_image_ctx *ictx)
>       return 0;
>  
>  err_file:
> -     fclose(fp);
>       fprintf(stderr, "ERR: Failed to load file \"%s\"\n",
>               ictx->cfg_filename);
>       return -EINVAL;

The whole code with the goto is ugly.  Such an error exit may make
sense when used in several places, but here it just makes reading
the code more difficult.  I suggest to fix this like this:


diff --git a/tools/mxsimage.c b/tools/mxsimage.c
index 002f4b525a..801aaa62ce 100644
--- a/tools/mxsimage.c
+++ b/tools/mxsimage.c
@@ -1595,8 +1595,11 @@ static int sb_load_cmdfile(struct sb_image_ctx *ictx)
        size_t len;
 
        fp = fopen(ictx->cfg_filename, "r");
-       if (!fp)
-               goto err_file;
+       if (!fp) {
+               fprintf(stderr, "ERR: Failed to load file \"%s\"\n",
+                       ictx->cfg_filename);
+               return -EINVAL;
+       }
 
        while ((rlen = getline(&line, &len, fp)) > 0) {
                memset(&cmd, 0, sizeof(cmd));
@@ -1616,12 +1619,6 @@ static int sb_load_cmdfile(struct sb_image_ctx *ictx)
        fclose(fp);
 
        return 0;
-
-err_file:
-       fclose(fp);
-       fprintf(stderr, "ERR: Failed to load file \"%s\"\n",
-               ictx->cfg_filename);
-       return -EINVAL;
 }
 
 static int sb_build_tree_from_cfg(struct sb_image_ctx *ictx)



Thanks.


Best regards,

Wolfgang Denk

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