Re: [patch] isdn: return -EFAULT if copy_from_user() fails

[David Miller <davem@davemloft.net>]

From: David Miller <davem@davemloft.net>
Date: Fri, 10 Dec 2010 16:47:21 -0800 (PST)

> From: Nicolas Kaiser <nikai@nikai.net>
> Date: Sat, 11 Dec 2010 01:41:54 +0100
> 
>> Ahem, we're printing this return value:
>> 
>> * Dan Carpenter <error27@gmail.com>:
>>> -	if ((ret = copy_from_user(&size, p, sizeof(int)))) {
>>              ^^^
>>> +	if (copy_from_user(&size, p, sizeof(int))) {
>>>  		printk(KERN_ERR"isar_load_firmware copy_from_user ret %d\n", ret);
>>                                                                              ^^^
>>> -		return ret;
>>> +		return -EFAULT;
> 
> I'll fix this, thanks.

As follows:

>From cf108fdd482e80161128c2ed01e7f4fb5bc728b9 Mon Sep 17 00:00:00 2001
From: David S. Miller <davem@davemloft.net>
Date: Fri, 10 Dec 2010 16:49:24 -0800
Subject: [PATCH] isdn: Fix printed out copy_from_user() return value after previous change.

Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/isdn/hisax/isar.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/isdn/hisax/isar.c b/drivers/isdn/hisax/isar.c
index c9cd4d2..313ce2d 100644
--- a/drivers/isdn/hisax/isar.c
+++ b/drivers/isdn/hisax/isar.c
@@ -189,7 +189,7 @@ ISARVersion(struct IsdnCardState *cs, char *s)
 static int
 isar_load_firmware(struct IsdnCardState *cs, u_char __user *buf)
 {
-	int ret, size, cnt, debug;
+	int cfu_ret, size, cnt, debug;
 	u_char len, nom, noc;
 	u_short sadr, left, *sp;
 	u_char __user *p = buf;
@@ -212,8 +212,9 @@ isar_load_firmware(struct IsdnCardState *cs, u_char __user *buf)
 	cs->debug &= ~(L1_DEB_HSCX | L1_DEB_HSCX_FIFO);
 #endif
 	
-	if (copy_from_user(&size, p, sizeof(int))) {
-		printk(KERN_ERR"isar_load_firmware copy_from_user ret %d\n", ret);
+	cfu_ret = copy_from_user(&size, p, sizeof(int));
+	if (cfu_ret) {
+		printk(KERN_ERR"isar_load_firmware copy_from_user ret %d\n", cfu_ret);
 		return -EFAULT;
 	}
 	p += sizeof(int);
-- 
1.7.3.2