From mboxrd@z Thu Jan 1 00:00:00 1970 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 5333A502D76; Tue, 13 Oct 2026 12:02:41 +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=1791892962; cv=none; b=LptSNKSTw4yac3tCJH9CxLeg9sNq/lw0P3fndz4BPbvCkrBSw9NY3MhSS5Ge2h2DNhyK/Q/4Nw/rsOuzolD+sTBKabu2vIIE5iMxFC6EzQ4cXtl3go50Bu79tP/fGwO/QsA7+FCumetEGFrci1Js/Jji5bWn+P3DKYtiYvs2O6g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791892962; c=relaxed/simple; bh=7IvscZlgcTcd3yYlhM5SIFA0EzombU7MV6wS9K2q8nM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bu9bIr4KlV9q1sjazI+e1MO4XoO3ZS7fzXQQot3V6lA+JMkCTkvm3U6b+QTi4Fe9uEIuTciYfswnBjBtlGMdJsStTSu/Ac/DGJDABy7i1hV/h3YoNYybt1L0wbc5HCGFC9W5lVoTntMq9l7uebIbc3K5RlF2MAC/5CwDhKz9u0Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SKs12ksx; 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="SKs12ksx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5FAE31F00898; Tue, 13 Oct 2026 12:02:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791892960; bh=81bxOyLDuSfE5VNIQ034eJBTpVjnG9Sahe5XGa8ZnS0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=SKs12ksx0kPl9B5Oxiie139T9NVBHSYS3Z1nzjLfxbzOj8hFkeWThfO4aO77l+TDU o09Ad9ZJSoNEAaQK8oeWbVnUKq8d4saHBHhaT83eAnBKMVuCgB53w5o6un2RigClpF /2PlSSGpUavv0OyNuLSSG2mn1bu2z7UjdRvSSqDE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ido Schimmel , Daehyeon Ko <4ncienth@gmail.com>, Jakub Kicinski Subject: [PATCH 6.18 022/621] ipv6: do not warn on route notification size race Date: Tue, 13 Oct 2026 13:30:17 +0200 Message-ID: <20261013112921.393074309@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261013112920.855194808@linuxfoundation.org> References: <20261013112920.855194808@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: Daehyeon Ko <4ncienth@gmail.com> commit c97426ec649d99596d8969e1a052c16b14b7b485 upstream. fib6_info_hw_flags_set() sizes the skb with rt6_nlmsg_size() and later fills it with rt6_fill_node(). With nexthop compatibility mode enabled, a concurrent replacement can grow the group between these independent snapshots. rt6_fill_node() can then legitimately return -EMSGSIZE, so the warning does not prove a sizing bug. Remove the warning. The existing error path still frees the skb and reports the error to listeners. Fixes: 907eea486888 ("net: ipv6: Emit notification when fib hardware flags are changed") Reported-by: Ido Schimmel Link: https://lore.kernel.org/netdev/20261007114003.GA1011260@shredder/ Suggested-by: Ido Schimmel Cc: stable@vger.kernel.org Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Link: https://patch.msgid.link/4012604727e5ba80b69ccd4d08796511397ddaef.1791423190.git.4ncienth@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/ipv6/route.c | 2 -- 1 file changed, 2 deletions(-) --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -6468,8 +6468,6 @@ void fib6_info_hw_flags_set(struct net * err = rt6_fill_node(net, skb, f6i, NULL, NULL, NULL, 0, RTM_NEWROUTE, 0, 0, 0); if (err < 0) { - /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ - WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; }