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 B6E4E1FC8 for ; Tue, 14 Apr 2026 11:56:13 +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=1776167773; cv=none; b=rKG/lJ/S/cNcaQ1iLb/J6jC5BLSo/2q+Z0JbCCanG49RtfaIDndSjHLauzYq/Ro15DItGOb04ti+l4GNgz0yw/d57yj0OFD/L89wEOmBaV9BExsocjaFtU50ctjGDAjXSAW703yYtX3qJhrY6J6rISpdbKyGRPkeFYNiRevA8HY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776167773; c=relaxed/simple; bh=EQBGI9VP1BsghsyEgYeLGsl360/Q21GEup8Rcy4I85A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GPEKbLfIE6CKWWrf7cj7O9LILoQg0qMWVvHxk+zwWcAhyX6KGBL8KH2indB1nC4FyLcm51b7abWdjC4KokW2R7uOtkKEK1frMlXotE4kOTOtLwfYEy7QkQ0FHedv6GsWU6HD028aUsW1UByhAYAAM1I64Ap8I5p2Y1ctGqv35I4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tYl4KoZ9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tYl4KoZ9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E900AC19425; Tue, 14 Apr 2026 11:56:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776167773; bh=EQBGI9VP1BsghsyEgYeLGsl360/Q21GEup8Rcy4I85A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tYl4KoZ9erShgElXIXYCtjVN0qWqF4P/DXiW8w+qDgau2SHAJT7oB9ktWjyUMXLO5 pQGvdaqbNPGOfjhJWJqa7HocmyzUOFUWFuNLK7jNOuph7JsdrXqjGCoYyJaq3EScmB 7EFokUFUfKJZghAl1j/hWpkvuCMloZeFxi+v6ulf6EcQMURqCvSmvN+LnIE09Owimu ctET36+cAqzGHPz/7UPkxJfS52v/3xK73rhaz8uWNxuqik+xdOlTGZTAZ0oPTm19QL HbX8zUfleYr9NZdmOlBdml855554HABVDDFwd15TBvQNzPeXArZb0KhkUYsZ9BvCtq NQDA8fx2S0pZg== From: Sasha Levin To: stable@vger.kernel.org Cc: Yuqi Xu , Yifan Wu , Juefei Pu , Yuan Tan , Xin Liu , Ren Wei , Ren Wei , David Howells , Marc Dionne , Simon Horman , linux-afs@lists.infradead.org, stable@kernel.org, Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15.y] rxrpc: reject undecryptable rxkad response tickets Date: Tue, 14 Apr 2026 07:56:10 -0400 Message-ID: <20260414115610.548230-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026041319-ethanol-outflank-3480@gregkh> References: <2026041319-ethanol-outflank-3480@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Yuqi Xu [ Upstream commit fe4447cd95623b1cfacc15f280aab73a6d7340b2 ] 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: Simon Horman cc: linux-afs@lists.infradead.org cc: stable@kernel.org Link: https://patch.msgid.link/20260408121252.2249051-12-dhowells@redhat.com Signed-off-by: Jakub Kicinski [ adapted `rxrpc_abort_conn()` call to existing `goto other_error` error-handling pattern ] Signed-off-by: Sasha Levin --- net/rxrpc/rxkad.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c index db47844f4ac99..45a64eafa2006 100644 --- a/net/rxrpc/rxkad.c +++ b/net/rxrpc/rxkad.c @@ -1013,8 +1013,13 @@ 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) { + abort_code = RXKADBADTICKET; + ret = -EPROTO; + goto other_error; + } p = ticket; end = p + ticket_len; -- 2.53.0