Re: [PATCH][next] fs: dlm: Fix memory leak of object mh

[Dan Carpenter]

On Wed, May 26, 2021 at 02:40:39PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> 
> There is an error return path that is not kfree'ing mh after
> it has been successfully allocates.  Fix this by free'ing it.
> 
> Addresses-Coverity: ("Resource leak")
> Fixes: a070a91cf140 ("fs: dlm: add more midcomms hooks")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
>  fs/dlm/rcom.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c
> index 085f21966c72..19298edc1573 100644
> --- a/fs/dlm/rcom.c
> +++ b/fs/dlm/rcom.c
> @@ -393,6 +393,7 @@ static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
>  	if (rc_in->rc_id == 0xFFFFFFFF) {
>  		log_error(ls, "receive_rcom_lookup dump from %d", nodeid);
>  		dlm_dump_rsb_name(ls, rc_in->rc_buf, len);
> +		kfree(mh);

Am I looking at the same code as you?  (I often am not able to review
your patches because you're doing development on stuff that hasn't hit
linux-next).  Anyway, to me this doesn't seem like the correct fix at
all.  There are some other things to free and the "mh" pointer is on
a bunch of lists so it leads to use after frees.

regards,
dan carpenter