From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71FB6C7EE45 for ; Mon, 12 Jun 2023 06:35:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234605AbjFLGfA (ORCPT ); Mon, 12 Jun 2023 02:35:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233442AbjFLGet (ORCPT ); Mon, 12 Jun 2023 02:34:49 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26CA51717 for ; Sun, 11 Jun 2023 23:29:49 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4D4A661F91 for ; Mon, 12 Jun 2023 06:27:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3BFA2C433D2; Mon, 12 Jun 2023 06:27:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686551239; bh=bygE85h9KYcNqUg72GSGqDuDJfHaYqHV6bmzobl7ohY=; h=Subject:To:Cc:From:Date:From; b=qlA6M8QPf138/DufkBAHwgUn8YzR76WhJxu5MdKZ8/H4ZH91AHJHiAvifFmCrxIXa uUf2o/BI5AWoZ/EwyNz/2F1L7ilLuBVkDQrFgvxKEJ++I5iS9OSnXdvmr24RUtfG5o CBJqPxN3ww1HPzJG7bksokd/mQGhigapfIVboT1E= Subject: FAILED: patch "[PATCH] ksmbd: fix out-of-bound read in deassemble_neg_contexts()" failed to apply to 5.15-stable tree To: linkinjeon@kernel.org, cc85nod@gmail.com, stfrench@microsoft.com Cc: From: Date: Mon, 12 Jun 2023 08:27:16 +0200 Message-ID: <2023061216-striking-darkened-f7a5@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x f1a411873c85b642f13b01f21b534c2bab81fc1b # git commit -s git send-email --to '' --in-reply-to '2023061216-striking-darkened-f7a5@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f1a411873c85b642f13b01f21b534c2bab81fc1b Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Sun, 28 May 2023 00:23:09 +0900 Subject: [PATCH] ksmbd: fix out-of-bound read in deassemble_neg_contexts() The check in the beginning is `clen + sizeof(struct smb2_neg_context) <= len_of_ctxts`, but in the end of loop, `len_of_ctxts` will subtract `((clen + 7) & ~0x7) + sizeof(struct smb2_neg_context)`, which causes integer underflow when clen does the 8 alignment. We should use `(clen + 7) & ~0x7` in the check to avoid underflow from happening. Then there are some variables that need to be declared unsigned instead of signed. [ 11.671070] BUG: KASAN: slab-out-of-bounds in smb2_handle_negotiate+0x799/0x1610 [ 11.671533] Read of size 2 at addr ffff888005e86cf2 by task kworker/0:0/7 ... [ 11.673383] Call Trace: [ 11.673541] [ 11.673679] dump_stack_lvl+0x33/0x50 [ 11.673913] print_report+0xcc/0x620 [ 11.674671] kasan_report+0xae/0xe0 [ 11.675171] kasan_check_range+0x35/0x1b0 [ 11.675412] smb2_handle_negotiate+0x799/0x1610 [ 11.676217] ksmbd_smb_negotiate_common+0x526/0x770 [ 11.676795] handle_ksmbd_work+0x274/0x810 ... Cc: stable@vger.kernel.org Signed-off-by: Chih-Yen Chang Tested-by: Chih-Yen Chang Signed-off-by: Namjae Jeon Signed-off-by: Steve French diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 7a81541de602..25c0ba04c59d 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -963,13 +963,13 @@ static void decode_sign_cap_ctxt(struct ksmbd_conn *conn, static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, struct smb2_negotiate_req *req, - int len_of_smb) + unsigned int len_of_smb) { /* +4 is to account for the RFC1001 len field */ struct smb2_neg_context *pctx = (struct smb2_neg_context *)req; int i = 0, len_of_ctxts; - int offset = le32_to_cpu(req->NegotiateContextOffset); - int neg_ctxt_cnt = le16_to_cpu(req->NegotiateContextCount); + unsigned int offset = le32_to_cpu(req->NegotiateContextOffset); + unsigned int neg_ctxt_cnt = le16_to_cpu(req->NegotiateContextCount); __le32 status = STATUS_INVALID_PARAMETER; ksmbd_debug(SMB, "decoding %d negotiate contexts\n", neg_ctxt_cnt); @@ -983,7 +983,7 @@ static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, while (i++ < neg_ctxt_cnt) { int clen, ctxt_len; - if (len_of_ctxts < sizeof(struct smb2_neg_context)) + if (len_of_ctxts < (int)sizeof(struct smb2_neg_context)) break; pctx = (struct smb2_neg_context *)((char *)pctx + offset); @@ -1038,9 +1038,8 @@ static __le32 deassemble_neg_contexts(struct ksmbd_conn *conn, } /* offsets must be 8 byte aligned */ - clen = (clen + 7) & ~0x7; - offset = clen + sizeof(struct smb2_neg_context); - len_of_ctxts -= clen + sizeof(struct smb2_neg_context); + offset = (ctxt_len + 7) & ~0x7; + len_of_ctxts -= offset; } return status; }