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 BE8023E3156; Wed, 30 Sep 2026 19:28:33 +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=1790796514; cv=none; b=aaseg9xVlfeyDGCdpUx+pGyBs482a6wgxr7k5NFPMA5hud6KoAtEwGUEMwiiZYEAEgBNaNWLZTiZBOzp9MzGJCFepManXrC3mmMi7A8apL8ZvfUDVH7CPKkHPx8HuXX+RawNFb/odwTkNLKG5UzmTr9L+UZuaaxX/UDkoKfZ1vc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790796514; c=relaxed/simple; bh=6hUxgZ0ksHWv2oUhnpn0nzcNPJSbZoqEigQpKvYSgYI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NXZGcp5zfAFIEWYZZrIONSvZ/mYEQHnTU7HAv8OOMYvWMdpSY1AJEHPn5IvUnk+11wKZHulOkhihDo0fLatRRh5TafLNqLO/TCnXq/N0yvuxTyo9u+j/7v8gtiW08ShjPhT0cfiWL0wbdZHcDA6E/7iGMNfH2/zbl/kZ7i7oDkc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=fWzho3W5; 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="fWzho3W5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E61581F000FF; Wed, 30 Sep 2026 19:28:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790796513; bh=MQJ2GSI9LfLCwfYQuXuLazx7o6koSiDuM3JiExpsExg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=fWzho3W51PWq2z3X/marNPoyy+sULfiO/pvVRuXffBb0UEoounssAxGPfOtKv+PSp JhQoUadmc99VAHAcT4U27R/c/pC9vtxfREYu/9EGBEgLrYCY58rzDCyqyEVwJSmLvM kD2UIHuPOrW9CbE4vxhQHwNP0GuwgtdFKZQLEfNM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Frank Sorenson , David Howells , Paulo Alcantara Subject: [PATCH 6.6 0939/1193] smb: client: fix server->total_read for compound encrypted PDUs Date: Wed, 30 Sep 2026 17:27:03 +0200 Message-ID: <20260930152455.101991876@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152434.301151190@linuxfoundation.org> References: <20260930152434.301151190@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Frank Sorenson commit f73726b83e4756fdaa099e1bc1143293bd57ad79 upstream. In receive_encrypted_standard(), server->total_read is left at the full decrypted frame size when walking sub-PDUs of a compound encrypted frame. As a result, cifs_handle_standard() passes this full size to smb2_check_message(), causing the PDU length guards to incorrectly validate the entire compound frame instead of the current sub-PDU. This allows truncated non-last sub-PDUs to bypass length validation, leading to out-of-bounds reads in smb2_get_data_area_len(). Fix this by setting server->total_read to the true length of the current sub-PDU: next_cmd for non-last sub-PDUs, and the remaining pdu_length for the last one. Fixes: b24df3e30cbf ("cifs: update receive_encrypted_standard to handle compounded responses") Cc: stable@vger.kernel.org Signed-off-by: Frank Sorenson Reviewed-by: David Howells Signed-off-by: Paulo Alcantara Signed-off-by: Greg Kroah-Hartman --- fs/smb/client/smb2ops.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -4975,6 +4975,7 @@ receive_encrypted_standard(struct TCP_Se one_more: shdr = (struct smb2_hdr *)buf; next_cmd = le32_to_cpu(shdr->NextCommand); + server->total_read = next_cmd ? next_cmd : pdu_length; if (*num_mids >= MAX_COMPOUND) { cifs_server_dbg(VFS, "too many PDUs in compound\n");