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 7782A3AFD16; Mon, 17 Aug 2026 14:27:05 +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=1786976826; cv=none; b=td1qYBDAKP3GihUg4i9vVRczKvisyptNr6krRXq3OvC4y/i7BddluW5v2UjlImKqH41Mp3wc26CRG9cuZA0uajPWrCRb/m2wZ2P5HmGs7vgUJfifYaJEU0R1/Of4yQVaVZdiPnuYaMFKhmsNMMEiOuvWqQZK4cDAioX5owzUIVY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786976826; c=relaxed/simple; bh=qRF/Q3iV0PcCfZe0E6ulA3KhcF4xP8OT3zeKD5k/JG8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YlkDNPTT/BiTHPk1OEc7nAVQeZQ804q2bXVMsmVcSL50TuIwZ24QNgnVjhoZbHXs5544r/SmAt8VrdM+88u/02baULtoYn+ZYHELr55XR2x1Y6kPL9KNcQxg3CQ8oUi3vU2ly0Ho9gUSA173j+IxkrbaA9aAFFndRojluHsMHdI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vD++Tjoc; 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="vD++Tjoc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFEDB1F000E9; Mon, 17 Aug 2026 14:27:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786976825; bh=O0LhHmZbYuc6455NnsGzGBUTVutgu4BVDIgUBJShyVI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=vD++Tjocf03p3+kdPzpxoXKuk7HOw7EHNphnEggAX63Ih15iWn4LwQgTH2Kmkf3ge LgWN86c0n6jITY6mwDmg+GIwi/HKYlXdoWudd+H4ICqVaBp5HkQ+8Tc725qSyJ9Rcf lVgiQfm/C43ZynfpfsH/NN3sq9SjdrYauTiP3ryA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qing Luo , Xin Long , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 118/456] sctp: auth: verify auth requirement when auth_chunk is NULL Date: Mon, 17 Aug 2026 15:28:28 +0200 Message-ID: <20260817132544.705401826@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132539.792407575@linuxfoundation.org> References: <20260817132539.792407575@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qing Luo [ Upstream commit 8e04823c120b376ef7dab14b60ebf6823aa16c14 ] sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when: 1. skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this. 2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never called and auth_chunk remains NULL. Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally. Fixes: bbd0d59809f9 ("[SCTP]: Implement the receive and verification of AUTH chunk") Signed-off-by: Qing Luo Acked-by: Xin Long Link: https://patch.msgid.link/20260721015532.120157-2-l1138897701@163.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sctp/sm_statefuns.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 572055ee129f86..d57ec436775059 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -639,7 +639,7 @@ static bool sctp_auth_chunk_verify(struct net *net, struct sctp_chunk *chunk, struct sctp_chunk auth; if (!chunk->auth_chunk) - return true; + return !sctp_auth_recv_cid(chunk->chunk_hdr->type, asoc); /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo * is supposed to be authenticated and we have to do delayed -- 2.53.0