Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3E85949D58C; Thu, 17 Sep 2026 17:21:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789665687; cv=none; b=K26iQ1KXVmcj9jWzBWyrBP6x9zH2L/fdjPDe2PhsNp1YjiKyNsvjmvzRgASkoRgs7xdz7rCUk3jIng58h/V5kKilYgNTVWeSXXia648SpxLYjimAKdMq4euFk1cgdaZh4tWqisXJhxTITlyFYLYuD1REqpsPE0C59C0z3jjEX9w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789665687; c=relaxed/simple; bh=yJuWz9ybUd7D3bNRMr4ZE4zIlM8c/gUaW+CAIysMpQA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KjFP+0lhFQFD8s1wyGPYLLzPC04rMhgzcZI16OPrDZDoD7RXCeth0Yk7Bia6aYe+jjjmf0aqodJ/3eYKc0hRTPwW+9B0BPgsyhRtOl6ptsrmEbceiTRZ2dl7tpbiAUkrLC/j0cW/ys4QNTfz0SqH2mTXgARW4ZC/tV3HravBe5k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=pgBRhDiq; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="pgBRhDiq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 94ED11F000FF; Thu, 17 Sep 2026 17:21:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789665686; bh=juvAF1ej/Jtv0UGTESquQVbuT8bh6SJVRqYPpXn3vUM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=pgBRhDiqkDAapnyqggNsIlDCJ+gl/4GCRzD1ush1aB0k29CY6wGVJNz+OSrTFq+rT 2Z02y7sB5lg6eBmvRHX45tNVXKkcAUZi7f8mL1eTdXDHyMLvpTQ8RCp8/svLpvvev0 3KhYSLEzjMQi75BVmRvdP2M4h5TiuO/g2gSJP2nI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ido Schimmel , Eric Dumazet , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 0788/1250] nexthop: Initialize extack in remove_nh_grp_entry() Date: Thu, 17 Sep 2026 16:09:43 +0100 Message-ID: <20260917151613.252932064@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151551.901433442@linuxfoundation.org> References: <20260917151551.901433442@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ido Schimmel [ Upstream commit 5bd9e4e7cdaa03879e9b73b12ab52cceb1edd55b ] remove_nh_grp_entry() prints the extack message when a listener fails to replace the reduced nexthop group. However, extack is not initialized and listeners are not required to set a message when returning an error. Neither netdevsim nor mlxsw do so when an allocation fails, resulting in the dereference of an uninitialized stack pointer. Fix by zero-initializing extack, as was done in commit 6347c5314cee ("nexthop: initialize extack in nh_res_bucket_migrate()"). Fixes: 833a1065eeb1 ("nexthop: Emit a notification when a nexthop group is reduced") Signed-off-by: Ido Schimmel Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20260903080259.10378-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/nexthop.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index a8bf1ec548995..66d5c996866bf 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -2025,7 +2025,7 @@ static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge, { struct nh_grp_entry *nhges, *new_nhges; struct nexthop *nhp = nhge->nh_parent; - struct netlink_ext_ack extack; + struct netlink_ext_ack extack = {}; struct nexthop *nh = nhge->nh; struct nh_group *nhg, *newg; int i, j, err; -- 2.53.0