public inbox for linux-cifs@vger.kernel.org
 help / color / mirror / Atom feed
From: Namjae Jeon <linkinjeon@kernel.org>
To: linux-cifs@vger.kernel.org
Cc: Namjae Jeon <linkinjeon@kernel.org>
Subject: [PATCH] ksmbd: validate compound response buffer
Date: Tue, 12 Oct 2021 10:20:05 +0900	[thread overview]
Message-ID: <20211012012006.5037-2-linkinjeon@kernel.org> (raw)
In-Reply-To: <20211012012006.5037-1-linkinjeon@kernel.org>

Add the check to validate compound response buffer.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
 fs/ksmbd/smb2pdu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 7b4689f2df49..89c187aa8db2 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -449,6 +449,12 @@ bool is_chained_smb2_message(struct ksmbd_work *work)
 			return false;
 		}
 
+		if ((u64)get_rfc1002_len(work->response_buf) + MAX_CIFS_SMALL_BUFFER_SIZE >
+		    work->response_sz) {
+			pr_err("next response offset exceeds response buffer size\n");
+			return false;
+		}
+
 		ksmbd_debug(SMB, "got SMB2 chained command\n");
 		init_chained_smb2_rsp(work);
 		return true;
-- 
2.25.1


      reply	other threads:[~2021-10-12  1:20 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-12  1:20 [PATCH] ksmbd: fix potencial 32bit overflow from data area check in smb2_write Namjae Jeon
2021-10-12  1:20 ` Namjae Jeon [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211012012006.5037-2-linkinjeon@kernel.org \
    --to=linkinjeon@kernel.org \
    --cc=linux-cifs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox