old buffer overflow in moxa driver

I noticed that the moxa input checking security bug described by
CVE-2005-0504 appears to remain unfixed upstream.

The issue is described here:
  http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-0504

Debian has been shipping the following patch from Andres Salomon.

(akpm: it's a privileged operation)

Signed-off-by: dann frazier <dannf@hp.com>
Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c
index 7dbaee8d..e0d35c2 100644
--- a/drivers/char/moxa.c
+++ b/drivers/char/moxa.c
@@ -1582,7 +1582,7 @@
 
 	if(copy_from_user(&dltmp, argp, sizeof(struct dl_str)))
 		return -EFAULT;
-	if(dltmp.cardno < 0 || dltmp.cardno >= MAX_BOARDS)
+	if(dltmp.cardno < 0 || dltmp.cardno >= MAX_BOARDS || dltmp.len < 0)
 		return -EINVAL;
 
 	switch(cmd)
@@ -2529,6 +2529,8 @@
 	void __iomem *baseAddr;
 	int i;
 
+	if(len < 0 || len > sizeof(moxaBuff))
+		return -EINVAL;
 	if(copy_from_user(moxaBuff, tmp, len))
 		return -EFAULT;
 	baseAddr = moxa_boards[cardno].basemem;
@@ -2576,7 +2578,7 @@
 	void __iomem *baseAddr;
 	int i;
 
-	if(len > sizeof(moxaBuff))
+	if(len < 0 || len > sizeof(moxaBuff))
 		return -EINVAL;
 	if(copy_from_user(moxaBuff, tmp, len))
 		return -EFAULT;
@@ -2596,6 +2598,8 @@
 	void __iomem *baseAddr, *ofsAddr;
 	int retval, port, i;
 
+	if(len < 0 || len > sizeof(moxaBuff))
+		return -EINVAL;
 	if(copy_from_user(moxaBuff, tmp, len))
 		return -EFAULT;
 	baseAddr = moxa_boards[cardno].basemem;