Re: [PATCH][next] NTB: ntb_tool: fix memory leak on 'buf' on error exit path

[Serge Semin]

On Mon, Jan 22, 2018 at 09:38:57AM +0000, Colin King <colin.king@xxxxxxxxxxxxx> wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> 
> Currently there is a memory leak on buf when the call to ntb_mw_get_align
> fails.  Add an exit err label and jump to this so that kfree on buf frees
> the memory.
> 
> Detected by CoverityScan, CID#1464286 ("Resource leak")
> 
> Fixes: d637628ce00c ("NTB: ntb_tool: Add full multi-port NTB API support")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Good catch, thanks!

Acked-by: Serge Semin <fancer.lancer@xxxxxxxxx>

> ---
>  drivers/ntb/test/ntb_tool.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ntb/test/ntb_tool.c b/drivers/ntb/test/ntb_tool.c
> index 920fc9b161b0..d592c0ffbd19 100644
> --- a/drivers/ntb/test/ntb_tool.c
> +++ b/drivers/ntb/test/ntb_tool.c
> @@ -659,7 +659,7 @@ static ssize_t tool_mw_trans_read(struct file *filep, char __user *ubuf,
>  	ret = ntb_mw_get_align(inmw->tc->ntb, inmw->pidx, inmw->widx,
>  			       &addr_align, &size_align, &size_max);
>  	if (ret)
> -		return ret;
> +		goto err;
>  
>  	off += scnprintf(buf + off, buf_size - off,
>  			 "Inbound MW     \t%d\n",
> @@ -694,6 +694,8 @@ static ssize_t tool_mw_trans_read(struct file *filep, char __user *ubuf,
>  			 &size_max);
>  
>  	ret = simple_read_from_buffer(ubuf, size, offp, buf, off);
> +
> +err:
>  	kfree(buf);
>  
>  	return ret;
> -- 
> 2.15.1
>