Re: [PATCH] net/handshake: Fix memory leak in tls_handshake_accept()

[Simon Horman <horms@kernel.org>]

On Thu, Nov 06, 2025 at 02:45:11PM +0000, Zilin Guan wrote:
> In tls_handshake_accept(), a netlink message is allocated using
> genlmsg_new(). In the error handling path, genlmsg_cancel() is called
> to cancel the message construction, but the message itself is not freed.
> This leads to a memory leak.
> 
> Fix this by calling nlmsg_free() in the error path after genlmsg_cancel()
> to release the allocated memory.
> 
> Fixes: 2fd5532044a89 ("net/handshake: Add a kernel API for requesting a TLSv1.3 handshake")
> Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
> ---
>  net/handshake/tlshd.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/net/handshake/tlshd.c b/net/handshake/tlshd.c
> index 081093dfd553..8f9532a15f43 100644
> --- a/net/handshake/tlshd.c
> +++ b/net/handshake/tlshd.c
> @@ -259,6 +259,7 @@ static int tls_handshake_accept(struct handshake_req *req,
>  
>  out_cancel:
>  	genlmsg_cancel(msg, hdr);

Hi Zilin Guan,

I don't think genlmsg_cancel() is necessary if msg is freed on the next line.
If so, I suggest removing it, and renaming out_cancel accordingly.

> +	nlmsg_free(msg);
>  out:
>  	return ret;
>  }
> -- 
> 2.34.1
>