From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA10A24B5B for ; Mon, 19 Feb 2024 09:54:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708336460; cv=none; b=qGpAR6+jN8s6bYFEaNRHBs7/dcH7Dzx9x2NcJD9Zt6XITZbWpOhmjXMVprB7ZeZwH30d+F7GW4zBELKjkTmgB7PeeiPZuY/OrH2nyBOPuHILetuuIDM5E5TymemGa5c4RMU4qMpvAdzg2jLtciJY4pBkG56IcdW0vdtmmrLS8nE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708336460; c=relaxed/simple; bh=eKHerGPEm1F87r5a7mg/1cWsJuRlXJiKhVep+HDLxh0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=R+QUyic1ovXgzec3BAhvVcXsQ+WWqEm/gWFIiGjfHqcTY7fjU3wlWQsVYkFciziV3BqPBTTLHEoJcg0NL/LBRTkcmoIEWEqILnE/yuOGMnOAbwktAs6PaCMhC6chKPgGs9SC9gfVdu7n7mGtG6GmI2AIb0ZOZDyu8SGWhjDvXE8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Sp7nDrH2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Sp7nDrH2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 045EBC433C7; Mon, 19 Feb 2024 09:54:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1708336460; bh=eKHerGPEm1F87r5a7mg/1cWsJuRlXJiKhVep+HDLxh0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Sp7nDrH2Mqp3D2zSx67dpacfwIA6q3rcY5WVWlmwaUeY/SIqUt2cqmiG47tC7LrAx NFhiS3clwx4c3S2YRVFqs78sVjlgCxJtIWJHILfwqbeaQjEm88jnC+vLB2l/O4kPJ8 kPJqcjz0LlLvQcBrPXIciCwO218P86d9Ro2zVPtwSkortU9IWf/2IFfdzfWc6jYY+h F5bLZlBGsAj588H/u/TV3XDhfqBznqmPP+pANOzjL5YU2HJkpXMpdkTe0Crwl4uVur g2smtLmHcD4kWqQOmW9BG0A0t44kzHi1ahplalKt5dl7IRsnBervhZjin4Ng7QqC1v SkutIXVLuDpXg== Date: Mon, 19 Feb 2024 09:52:47 +0000 From: Simon Horman To: Jeremy Kerr Cc: netdev@vger.kernel.org, Matt Johnston , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Subject: Re: [PATCH net] net: mctp: take ownership of skb in mctp_local_output Message-ID: <20240219095247.GV40273@kernel.org> References: Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Feb 15, 2024 at 03:53:09PM +0800, Jeremy Kerr wrote: > Currently, mctp_local_output only takes ownership of skb on success, and > we may leak an skb if mctp_local_output fails in specific states; the > skb ownership isn't transferred until the actual output routing occurs. > > Instead, make mctp_local_output free the skb on all error paths up to > the route action, so it always consumes the passed skb. > > Fixes: 833ef3b91de6 ("mctp: Populate socket implementation") > Signed-off-by: Jeremy Kerr ... > diff --git a/net/mctp/route.c b/net/mctp/route.c > index 7a47a58aa54b..a64788bc40a8 100644 > --- a/net/mctp/route.c > +++ b/net/mctp/route.c > @@ -888,7 +888,7 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, > dev = dev_get_by_index_rcu(sock_net(sk), cb->ifindex); > if (!dev) { > rcu_read_unlock(); > - return rc; > + goto out_free; > } > rt->dev = __mctp_dev_get(dev); > rcu_read_unlock(); > @@ -903,7 +903,7 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, > rt->mtu = 0; > > } else { > - return -EINVAL; > + goto out_free; Hi Jeremy, Previously this path returned -EINVAL. Now it will return rc. But by my reading rc is set to -ENODEV here. Should that be addressed? > } > > spin_lock_irqsave(&rt->dev->addrs_lock, flags); > @@ -966,12 +966,17 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, > rc = mctp_do_fragment_route(rt, skb, mtu, tag); > } > > + /* route output functions consume the skb, even on error */ > + skb = NULL; > + > out_release: > if (!ext_rt) > mctp_route_release(rt); > > mctp_dev_put(tmp_rt.dev); > > +out_free: > + kfree_skb(skb); > return rc; > } > > -- > 2.39.2 > >