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 361B41A08A4; Wed, 23 Apr 2025 15:32:18 +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=1745422340; cv=none; b=mtMmVmTK0+mdwjHLBmAdlA2CbaJDn5/+mouXAk4BmbT8beinqo49I2Bpqfkx3RIIC2Tz28vygyWLO0ia6atKxcTciDYgYgytYXkrKHfGpOe154sNqUrM6XuxGvIKHi2vbothhWFoP8i7n/WCQbBraWZNnCMEIW2A1DLYgf/erJs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745422340; c=relaxed/simple; bh=JxFunUZSS6wB1LFTdhtxS7CkJIHUk8nn2Kbut9CmStM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=atcJf2J9pkHgCV86EXjrV6A7GYtHAccCNwKkQA1Z8vUecVk5SConKrmFEpOGgR7gX3RODkBfHp3bKq32Pwe/jhhf55TPrQh2QG7ZL2PerjxAYVM29P5Q80i4/P6fylmEofmOnjf7g5MoN//qx1Uquu/J91Kbelddc34W2l4fX8Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0DXNB/+c; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="0DXNB/+c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5641FC4CEE2; Wed, 23 Apr 2025 15:32:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745422338; bh=JxFunUZSS6wB1LFTdhtxS7CkJIHUk8nn2Kbut9CmStM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0DXNB/+cuqvOjQ2J2gwT18q7oV9an1hPuZCbpx7pt4kOwXiFNFNZpeE9m18Z/LVGo 6rH9UVlOZPv9aVTQNaTWTCfub9Pg0K0MPn+SKMlDs2Mbk4K2sIWpGRMl8iCf2+PAbF jh3evGDbnQm+bnv4K+97oJF5oQys4TCbwbDYU+EY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Michal Swiatkowski , Jakub Kicinski , Jamal Hadi Salim , "David S. Miller" , Jianqi Ren , He Zhe Subject: [PATCH 6.1 279/291] net/sched: act_mirred: dont override retval if we already lost the skb Date: Wed, 23 Apr 2025 16:44:28 +0200 Message-ID: <20250423142635.829213900@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250423142624.409452181@linuxfoundation.org> References: <20250423142624.409452181@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jakub Kicinski commit 166c2c8a6a4dc2e4ceba9e10cfe81c3e469e3210 upstream. If we're redirecting the skb, and haven't called tcf_mirred_forward(), yet, we need to tell the core to drop the skb by setting the retcode to SHOT. If we have called tcf_mirred_forward(), however, the skb is out of our hands and returning SHOT will lead to UaF. Move the retval override to the error path which actually need it. Reviewed-by: Michal Swiatkowski Fixes: e5cf1baf92cb ("act_mirred: use TC_ACT_REINSERT when possible") Signed-off-by: Jakub Kicinski Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller [Minor conflict resolved due to code context change.] Signed-off-by: Jianqi Ren Signed-off-by: He Zhe Signed-off-by: Greg Kroah-Hartman --- net/sched/act_mirred.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -259,13 +259,13 @@ static int tcf_mirred_act(struct sk_buff dev = rcu_dereference_bh(m->tcfm_dev); if (unlikely(!dev)) { pr_notice_once("tc mirred: target device is gone\n"); - goto out; + goto err_cant_do; } if (unlikely(!(dev->flags & IFF_UP)) || !netif_carrier_ok(dev)) { net_notice_ratelimited("tc mirred to Houston: device %s is down\n", dev->name); - goto out; + goto err_cant_do; } /* we could easily avoid the clone only if called by ingress and clsact; @@ -279,7 +279,7 @@ static int tcf_mirred_act(struct sk_buff if (!use_reinsert) { skb2 = skb_clone(skb, GFP_ATOMIC); if (!skb2) - goto out; + goto err_cant_do; } want_ingress = tcf_mirred_act_wants_ingress(m_eaction); @@ -321,12 +321,16 @@ static int tcf_mirred_act(struct sk_buff } err = tcf_mirred_forward(want_ingress, skb2); - if (err) { -out: + if (err) tcf_action_inc_overlimit_qstats(&m->common); - if (tcf_mirred_is_act_redirect(m_eaction)) - retval = TC_ACT_SHOT; - } + __this_cpu_dec(mirred_nest_level); + + return retval; + +err_cant_do: + if (is_redirect) + retval = TC_ACT_SHOT; + tcf_action_inc_overlimit_qstats(&m->common); __this_cpu_dec(mirred_nest_level); return retval;