From patchwork Tue Sep 21 22:51:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Namjae Jeon X-Patchwork-Id: 12509033 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59C81C433F5 for ; Tue, 21 Sep 2021 22:51:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 301C661100 for ; Tue, 21 Sep 2021 22:51:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230082AbhIUWw5 (ORCPT ); Tue, 21 Sep 2021 18:52:57 -0400 Received: from mail-pg1-f171.google.com ([209.85.215.171]:44830 "EHLO mail-pg1-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229589AbhIUWw4 (ORCPT ); Tue, 21 Sep 2021 18:52:56 -0400 Received: by mail-pg1-f171.google.com with SMTP id s11so564795pgr.11 for ; Tue, 21 Sep 2021 15:51:27 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=TscF5aL76QOIfd+LuFeUnYJd6cstd4+TrgvEpI/mcHk=; b=cOmTV8rykOzWPLBlpktaoKt1xJO0AZr3m1aMbmsnz3NjJH1U9/qZ3vhxbjUw8B64yl 7vLvetSrGNSwCNzAdYajQp+OCgp43fxPTcHIKGU1GDe6SQCOvXI2tMdH7By797TDi0Y0 z5dDXnL5v0AG6WXFTWxvSabIVhc2cXzUNTjTe3fP5LWVJcFnkALaGB1NELq8nMjP43g5 nnNSw406is7wXSRBDnLJf13nqb/Cs/JTNmqggwPXHYhicqC1oUTI/lueidT2n3rNLgu3 YeNCRgsTe6Iih/j6rZXwfO6c3ubnbQgkHcaRFeo1kXKW8hYEEs83sRN8ma6zqD4pjA/c tJJA== X-Gm-Message-State: AOAM531Xpy/cQiQqKqn0ufxdukZe2GQHStohrhLpHI0wzCZIFQwWq+lE o+U0wrgC9NPuSx7LwZ5+XfJrvbot6UzECw== X-Google-Smtp-Source: ABdhPJwxE8jr/AY3U4/5C2OcGVPO1ssuFbTy0KXCJO5pys0WJdaJTCPtuceY6ADvRdcxMkP2NRQOQA== X-Received: by 2002:a63:185b:: with SMTP id 27mr30401311pgy.0.1632264687475; Tue, 21 Sep 2021 15:51:27 -0700 (PDT) Received: from localhost.localdomain ([61.74.27.164]) by smtp.gmail.com with ESMTPSA id e18sm167053pfj.159.2021.09.21.15.51.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Sep 2021 15:51:27 -0700 (PDT) From: Namjae Jeon To: linux-cifs@vger.kernel.org Cc: Namjae Jeon , Ronnie Sahlberg , =?utf-8?q?Ralph_B=C3=B6hme?= , Steve French Subject: [PATCH v2 2/3] ksmbd: add validation in smb2 negotiate Date: Wed, 22 Sep 2021 07:51:08 +0900 Message-Id: <20210921225109.6388-2-linkinjeon@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210921225109.6388-1-linkinjeon@kernel.org> References: <20210921225109.6388-1-linkinjeon@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org This patch add validation to check request buffer check in smb2 negotiate. Cc: Ronnie Sahlberg Cc: Ralph Böhme Cc: Steve French Signed-off-by: Namjae Jeon --- fs/ksmbd/smb2pdu.c | 41 ++++++++++++++++++++++++++++++++++++++++- fs/ksmbd/smb_common.c | 22 ++++++++++++++++++++-- 2 files changed, 60 insertions(+), 3 deletions(-) diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index baf7ce31d557..1fe37ad4e5bc 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1071,7 +1071,7 @@ int smb2_handle_negotiate(struct ksmbd_work *work) struct ksmbd_conn *conn = work->conn; struct smb2_negotiate_req *req = work->request_buf; struct smb2_negotiate_rsp *rsp = work->response_buf; - int rc = 0; + int rc = 0, smb2_buf_len, smb2_neg_size; __le32 status; ksmbd_debug(SMB, "Received negotiate request\n"); @@ -1089,6 +1089,45 @@ int smb2_handle_negotiate(struct ksmbd_work *work) goto err_out; } + smb2_buf_len = get_rfc1002_len(work->request_buf); + smb2_neg_size = offsetof(struct smb2_negotiate_req, Dialects) - 4; + if (conn->dialect == SMB311_PROT_ID) { + int nego_ctxt_off = le32_to_cpu(req->NegotiateContextOffset); + int nego_ctxt_count = le16_to_cpu(req->NegotiateContextCount); + + if (smb2_buf_len < nego_ctxt_off + nego_ctxt_count) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + + if (smb2_neg_size > nego_ctxt_off) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + + if (smb2_neg_size + le16_to_cpu(req->DialectCount) * sizeof(__le16) > + nego_ctxt_off) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + } else { + if (smb2_neg_size > smb2_buf_len) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + + if (smb2_neg_size + le16_to_cpu(req->DialectCount) * sizeof(__le16) > + smb2_buf_len) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + } + conn->cli_cap = le32_to_cpu(req->Capabilities); switch (conn->dialect) { case SMB311_PROT_ID: diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c index 1da67217698d..da17b21ac685 100644 --- a/fs/ksmbd/smb_common.c +++ b/fs/ksmbd/smb_common.c @@ -229,13 +229,22 @@ int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count) static int ksmbd_negotiate_smb_dialect(void *buf) { - __le32 proto; + int smb_buf_length = get_rfc1002_len(buf); + __le32 proto = ((struct smb2_hdr *)buf)->ProtocolId; - proto = ((struct smb2_hdr *)buf)->ProtocolId; if (proto == SMB2_PROTO_NUMBER) { struct smb2_negotiate_req *req; + int smb2_neg_size = + offsetof(struct smb2_negotiate_req, Dialects) - 4; req = (struct smb2_negotiate_req *)buf; + if (smb2_neg_size > smb_buf_length) + goto err_out; + + if (smb2_neg_size + le16_to_cpu(req->DialectCount) * sizeof(__le16) > + smb_buf_length) + goto err_out; + return ksmbd_lookup_dialect_by_id(req->Dialects, req->DialectCount); } @@ -245,10 +254,19 @@ static int ksmbd_negotiate_smb_dialect(void *buf) struct smb_negotiate_req *req; req = (struct smb_negotiate_req *)buf; + if (le16_to_cpu(req->ByteCount) < 2) + goto err_out; + + if (offsetof(struct smb_negotiate_req, DialectsArray) - 4 + + le16_to_cpu(req->ByteCount) > smb_buf_length) { + goto err_out; + } + return ksmbd_lookup_dialect_by_name(req->DialectsArray, req->ByteCount); } +err_out: return BAD_PROT_ID; }