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 AF4223AE6B for ; Wed, 7 Jun 2023 20:32:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3153DC4339B; Wed, 7 Jun 2023 20:32:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686169958; bh=8v6Fac6SZ6ouCapkxCHC4pGmbw5oXxrFrM6Yu0uxpZc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kgaVIgg4cGcqsEuYfWiFCuWtUsgL3h5QUe59BIDZKkTDzvH2AAxg/lPMZI01nDDql /n17TAh9uXkCU8hJYfPdBQ6wd0naonGCvPT/7w4/AfqTZh/7oBO2FPFJLtXOcupT7l 3zWQ8eBxzBteWKf5+m/99KD6CQunjGXWuWlBGYd4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Kuan-Ting Chen , Namjae Jeon , Steve French Subject: [PATCH 6.3 278/286] ksmbd: fix slab-out-of-bounds read in smb2_handle_negotiate Date: Wed, 7 Jun 2023 22:16:17 +0200 Message-ID: <20230607200932.367681541@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230607200922.978677727@linuxfoundation.org> References: <20230607200922.978677727@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Kuan-Ting Chen commit d738950f112c8f40f0515fe967db998e8235a175 upstream. Check request_buf length first to avoid out-of-bounds read by req->DialectCount. [ 3350.990282] BUG: KASAN: slab-out-of-bounds in smb2_handle_negotiate+0x35d7/0x3e60 [ 3350.990282] Read of size 2 at addr ffff88810ad61346 by task kworker/5:0/276 [ 3351.000406] Workqueue: ksmbd-io handle_ksmbd_work [ 3351.003499] Call Trace: [ 3351.006473] [ 3351.006473] dump_stack_lvl+0x8d/0xe0 [ 3351.006473] print_report+0xcc/0x620 [ 3351.006473] kasan_report+0x92/0xc0 [ 3351.006473] smb2_handle_negotiate+0x35d7/0x3e60 [ 3351.014760] ksmbd_smb_negotiate_common+0x7a7/0xf00 [ 3351.014760] handle_ksmbd_work+0x3f7/0x12d0 [ 3351.014760] process_one_work+0xa85/0x1780 Cc: stable@vger.kernel.org Signed-off-by: Kuan-Ting Chen Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/ksmbd/smb2pdu.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1081,16 +1081,16 @@ int smb2_handle_negotiate(struct ksmbd_w return rc; } - if (req->DialectCount == 0) { - pr_err("malformed packet\n"); + smb2_buf_len = get_rfc1002_len(work->request_buf); + smb2_neg_size = offsetof(struct smb2_negotiate_req, Dialects); + if (smb2_neg_size > smb2_buf_len) { rsp->hdr.Status = STATUS_INVALID_PARAMETER; rc = -EINVAL; goto err_out; } - smb2_buf_len = get_rfc1002_len(work->request_buf); - smb2_neg_size = offsetof(struct smb2_negotiate_req, Dialects); - if (smb2_neg_size > smb2_buf_len) { + if (req->DialectCount == 0) { + pr_err("malformed packet\n"); rsp->hdr.Status = STATUS_INVALID_PARAMETER; rc = -EINVAL; goto err_out;