From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f50.google.com (mail-pj1-f50.google.com [209.85.216.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3671E71469 for ; Mon, 18 Dec 2023 15:40:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pj1-f50.google.com with SMTP id 98e67ed59e1d1-28b5f4a1b48so1676665a91.2 for ; Mon, 18 Dec 2023 07:40:27 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702914026; x=1703518826; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=wUeAFnXPzz37W5frsfNFs63mkTMKw7FVXw7I1Ks2E10=; b=hwfJYgdq8rQrkqqDof+ccy4Gn0UeoHxiipRVPHlDpsWTtZvTM3oZnBy6DluvlYXigV D6e7qZMfJsCmn2vB4sPhUsw8e4vughRrCk+qFxbmH0tRKQ9JfI5AEm+L0hTAPc7RCbJV V0L3Qly2P75AUFlOeekGQE0P0g09cogYgX1jmkE5OPCfJJ7rFgbqrr8kmmeZHsVDpFML SiS+L9eePZFTeeHndNRmFIDS3ZcYwqx+IeW4WYHkGuWLJh8htHsXunY2xrbeCnjbgxZE rgSPhTWqIJSWovi+gTIj9N5uT3oxh5i3ama9prbOhf/2GkvcyKdyl4AW9cDCSeooiSyF ru0Q== X-Gm-Message-State: AOJu0Ywel1InIkYGwmXHxd2AvgA9acFbhyphW9QxSx7uEuKOsO3qb/4M jm1YgfdqeWFpLpV+dPKh3/Dt8FDjMIY= X-Google-Smtp-Source: AGHT+IGiDOOpXeXdWRk2I3uv1ehfgB1tSMRBNCzlSaj1Y1Iz6ouN7P7aAnnQzik5OMipgr5WZ4f9Lw== X-Received: by 2002:a17:90a:dc18:b0:28b:9035:632c with SMTP id i24-20020a17090adc1800b0028b9035632cmr837665pjv.51.1702914026465; Mon, 18 Dec 2023 07:40:26 -0800 (PST) Received: from localhost.localdomain ([110.14.71.32]) by smtp.gmail.com with ESMTPSA id fs7-20020a17090af28700b00286ed94466dsm5613041pjb.32.2023.12.18.07.40.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Dec 2023 07:40:26 -0800 (PST) From: Namjae Jeon To: gregkh@linuxfoundation.org, stable@vger.kernel.org Cc: smfrench@gmail.com, Kuan-Ting Chen , Namjae Jeon , Steve French Subject: [PATCH 5.15.y 095/154] ksmbd: fix multiple out-of-bounds read during context decoding Date: Tue, 19 Dec 2023 00:33:55 +0900 Message-Id: <20231218153454.8090-96-linkinjeon@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231218153454.8090-1-linkinjeon@kernel.org> References: <20231218153454.8090-1-linkinjeon@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Kuan-Ting Chen [ Upstream commit 0512a5f89e1fae74251fde6893ff634f1c96c6fb ] Check the remaining data length before accessing the context structure to ensure that the entire structure is contained within the packet. Additionally, since the context data length `ctxt_len` has already been checked against the total packet length `len_of_ctxts`, update the comparison to use `ctxt_len`. Cc: stable@vger.kernel.org Signed-off-by: Kuan-Ting Chen Acked-by: Namjae Jeon Signed-off-by: Steve French --- fs/ksmbd/smb2pdu.c | 53 +++++++++++++++++++++++++++++----------------- 1 file changed, 34 insertions(+), 19 deletions(-) diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 0e6f39f05af2..62bcc440ad31 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -879,13 +879,14 @@ static void assemble_neg_contexts(struct ksmbd_conn *conn, static __le32 decode_preauth_ctxt(struct ksmbd_conn *conn, struct smb2_preauth_neg_context *pneg_ctxt, - int len_of_ctxts) + int ctxt_len) { /* * sizeof(smb2_preauth_neg_context) assumes SMB311_SALT_SIZE Salt, * which may not be present. Only check for used HashAlgorithms[1]. */ - if (len_of_ctxts < 6) + if (ctxt_len < + sizeof(struct smb2_neg_context) + 6) return STATUS_INVALID_PARAMETER; if (pneg_ctxt->HashAlgorithms != SMB2_PREAUTH_INTEGRITY_SHA512) @@ -897,15 +898,23 @@ static __le32 decode_preauth_ctxt(struct ksmbd_conn *conn, static void decode_encrypt_ctxt(struct ksmbd_conn *conn, struct smb2_encryption_neg_context *pneg_ctxt, - int len_of_ctxts) + int ctxt_len) { - int cph_cnt = le16_to_cpu(pneg_ctxt->CipherCount); - int i, cphs_size = cph_cnt * sizeof(__le16); + int cph_cnt; + int i, cphs_size; + + if (sizeof(struct smb2_encryption_neg_context) > ctxt_len) { + pr_err("Invalid SMB2_ENCRYPTION_CAPABILITIES context size\n"); + return; + } conn->cipher_type = 0; + cph_cnt = le16_to_cpu(pneg_ctxt->CipherCount); + cphs_size = cph_cnt * sizeof(__le16); + if (sizeof(struct smb2_encryption_neg_context) + cphs_size > - len_of_ctxts) { + ctxt_len) { pr_err("Invalid cipher count(%d)\n", cph_cnt); return; } @@ -953,15 +962,22 @@ static void decode_compress_ctxt(struct ksmbd_conn *conn, static void decode_sign_cap_ctxt(struct ksmbd_conn *conn, struct smb2_signing_capabilities *pneg_ctxt, - int len_of_ctxts) + int ctxt_len) { - int sign_algo_cnt = le16_to_cpu(pneg_ctxt->SigningAlgorithmCount); - int i, sign_alos_size = sign_algo_cnt * sizeof(__le16); + int sign_algo_cnt; + int i, sign_alos_size; + + if (sizeof(struct smb2_signing_capabilities) > ctxt_len) { + pr_err("Invalid SMB2_SIGNING_CAPABILITIES context length\n"); + return; + } conn->signing_negotiated = false; + sign_algo_cnt = le16_to_cpu(pneg_ctxt->SigningAlgorithmCount); + sign_alos_size = sign_algo_cnt * sizeof(__le16); if (sizeof(struct smb2_signing_capabilities) + sign_alos_size > - len_of_ctxts) { + ctxt_len) { pr_err("Invalid signing algorithm count(%d)\n", sign_algo_cnt); return; } @@ -999,18 +1015,16 @@ static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, len_of_ctxts = len_of_smb - offset; while (i++ < neg_ctxt_cnt) { - int clen; - - /* check that offset is not beyond end of SMB */ - if (len_of_ctxts == 0) - break; + int clen, ctxt_len; if (len_of_ctxts < sizeof(struct smb2_neg_context)) break; pctx = (struct smb2_neg_context *)((char *)pctx + offset); clen = le16_to_cpu(pctx->DataLength); - if (clen + sizeof(struct smb2_neg_context) > len_of_ctxts) + ctxt_len = clen + sizeof(struct smb2_neg_context); + + if (ctxt_len > len_of_ctxts) break; if (pctx->ContextType == SMB2_PREAUTH_INTEGRITY_CAPABILITIES) { @@ -1021,7 +1035,7 @@ static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, status = decode_preauth_ctxt(conn, (struct smb2_preauth_neg_context *)pctx, - len_of_ctxts); + ctxt_len); if (status != STATUS_SUCCESS) break; } else if (pctx->ContextType == SMB2_ENCRYPTION_CAPABILITIES) { @@ -1032,7 +1046,7 @@ static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, decode_encrypt_ctxt(conn, (struct smb2_encryption_neg_context *)pctx, - len_of_ctxts); + ctxt_len); } else if (pctx->ContextType == SMB2_COMPRESSION_CAPABILITIES) { ksmbd_debug(SMB, "deassemble SMB2_COMPRESSION_CAPABILITIES context\n"); @@ -1051,9 +1065,10 @@ static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, } else if (pctx->ContextType == SMB2_SIGNING_CAPABILITIES) { ksmbd_debug(SMB, "deassemble SMB2_SIGNING_CAPABILITIES context\n"); + decode_sign_cap_ctxt(conn, (struct smb2_signing_capabilities *)pctx, - len_of_ctxts); + ctxt_len); } /* offsets must be 8 byte aligned */ -- 2.25.1