[PATCH 1/5] cifs: change bleft in decode_unicode_ssetup back to signed type

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The buffer length checks in this function depend on this value being a
signed data type, but 690c522fa converted it to an unsigned type.

Also, eliminate a problem with the null termination check in the same
function. cifs_strndup_from_ucs handles that situation correctly
already, and the existing check could potentially lead to a buffer
overrun since it increments bleft without checking to see whether it
falls off the end of the buffer.

Cc: stable@xxxxxxxxxx
Reported-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
 fs/cifs/sess.c |   15 +--------------
 1 files changed, 1 insertions(+), 14 deletions(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index f6728eb..2e2c911 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -276,7 +276,7 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
 }
 
 static void
-decode_unicode_ssetup(char **pbcc_area, __u16 bleft, struct cifsSesInfo *ses,
+decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifsSesInfo *ses,
 		      const struct nls_table *nls_cp)
 {
 	int len;
@@ -284,19 +284,6 @@ decode_unicode_ssetup(char **pbcc_area, __u16 bleft, struct cifsSesInfo *ses,
 
 	cFYI(1, "bleft %d", bleft);
 
-	/*
-	 * Windows servers do not always double null terminate their final
-	 * Unicode string. Check to see if there are an uneven number of bytes
-	 * left. If so, then add an extra NULL pad byte to the end of the
-	 * response.
-	 *
-	 * See section 2.7.2 in "Implementing CIFS" for details
-	 */
-	if (bleft % 2) {
-		data[bleft] = 0;
-		++bleft;
-	}
-
 	kfree(ses->serverOS);
 	ses->serverOS = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
 	cFYI(1, "serverOS=%s", ses->serverOS);
-- 
1.7.4.4

--
To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux