From 4991a5faab7368daac463181e786608b4eb63675 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 31 Jan 2012 11:52:01 +0300 Subject: [PATCH] cifs: check offset in decode_ntlmssp_challenge() We should check that we're not copying memory from beyond the end of the blob. Signed-off-by: Dan Carpenter Reviewed-by: Jeff Layton --- fs/cifs/sess.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index d85efad5765f..eb767412177d 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -395,6 +395,10 @@ static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len, ses->ntlmssp->server_flags = le32_to_cpu(pblob->NegotiateFlags); tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset); tilen = le16_to_cpu(pblob->TargetInfoArray.Length); + if (tioffset > blob_len || tioffset + tilen > blob_len) { + cERROR(1, "tioffset + tilen too high %u + %u", tioffset, tilen); + return -EINVAL; + } if (tilen) { ses->auth_key.response = kmalloc(tilen, GFP_KERNEL); if (!ses->auth_key.response) { -- 2.39.5