From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 0A6DB3F8E05 for ; Wed, 1 Apr 2026 10:57:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775041068; cv=none; b=kt+s/tn2PqvxZJhlTjVupFmPGCceTvqDnKxqx7QQuzGcNRKKPJ2Jb+InxEDAuv5AIAZmt4miDf/CBR4DlISUEqKeh0vwnddrct7fQhqy4FyqTeEbHEIACpFztQqwRp83tecnDGaZa7Ga4iXJ+6NW3elHS/saXg391ycBCE5f2CU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775041068; c=relaxed/simple; bh=7MLTMlM7F0ak10w0E2LplrY8tvTboOdFeE2eoMmUNUM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=r1eIPdiagYXphSYovUDDj+8K1hcbykBwGQBG4TRUn8+QrVQ0q4/zWaiwY75yxcV7CNt4dLPUZp7sDm+iPO8skN7f3ju3YhDTZZg6C1Nc+bpqXps7xcRDdWBjMuxPFWIMRRo4EAwYPZa5PJYKYCVxM4/a8dKpaIJkUV30OCqCRew= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Sg2kHDmo; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Sg2kHDmo" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1775041062; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KppfArEcP/QUXz58nWtzKdGZYsRDSnk43Kui514i9+Q=; b=Sg2kHDmoOXQzaDOT4ohyA/J13p2ds4CM3rp469us2OhbiaausKnG4trNo80corXNifqJu7 oaLL7sJV3oUHpF6K2SrUjoYcRwXLy57Cwc4DH5cEDMEZz9tamJnvIE24A6NgN5ERLboS8K IaDvgEFdwcQ0ihCiiS4XFRqNCEm0f/k= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-352-VupY1O3zNxKC3hBNVmvdzQ-1; Wed, 01 Apr 2026 06:57:41 -0400 X-MC-Unique: VupY1O3zNxKC3hBNVmvdzQ-1 X-Mimecast-MFC-AGG-ID: VupY1O3zNxKC3hBNVmvdzQ_1775041058 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9EE7F195608B; Wed, 1 Apr 2026 10:57:38 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.44.35.245]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id E16581953947; Wed, 1 Apr 2026 10:57:32 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , Marc Dionne , Jakub Kicinski , "David S. Miller" , Eric Dumazet , Paolo Abeni , linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org, Yuqi Xu , Yifan Wu , Juefei Pu , Yuan Tan , Xin Liu , Ren Wei , Ren Wei , Simon Horman , stable@kernel.org Subject: [PATCH net v4 12/15] rxrpc: reject undecryptable rxkad response tickets Date: Wed, 1 Apr 2026 11:56:05 +0100 Message-ID: <20260401105614.1696001-13-dhowells@redhat.com> In-Reply-To: <20260401105614.1696001-1-dhowells@redhat.com> References: <20260401105614.1696001-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 From: Yuqi Xu rxkad_decrypt_ticket() decrypts the RXKAD response ticket and then parses the buffer as plaintext without checking whether crypto_skcipher_decrypt() succeeded. A malformed RESPONSE can therefore use a non-block-aligned ticket length, make the decrypt operation fail, and still drive the ticket parser with attacker-controlled bytes. Check the decrypt result and abort the connection with RXKADBADTICKET when ticket decryption fails. Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Tested-by: Ren Wei Signed-off-by: Yuqi Xu Signed-off-by: Ren Wei Signed-off-by: David Howells cc: Marc Dionne cc: Eric Dumazet cc: "David S. Miller" cc: Jakub Kicinski cc: Paolo Abeni cc: Simon Horman cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: stable@kernel.org --- net/rxrpc/rxkad.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c index e923d6829008..0f79d694cb08 100644 --- a/net/rxrpc/rxkad.c +++ b/net/rxrpc/rxkad.c @@ -958,6 +958,7 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn, struct in_addr addr; unsigned int life; time64_t issue, now; + int ret; bool little_endian; u8 *p, *q, *name, *end; @@ -977,8 +978,11 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn, sg_init_one(&sg[0], ticket, ticket_len); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, sg, ticket_len, iv.x); - crypto_skcipher_decrypt(req); + ret = crypto_skcipher_decrypt(req); skcipher_request_free(req); + if (ret < 0) + return rxrpc_abort_conn(conn, skb, RXKADBADTICKET, -EPROTO, + rxkad_abort_resp_tkt_short); p = ticket; end = p + ticket_len;