[PATCH] Hamradio: Fix a NULL pointer dereference in net/hamradio/mkiss.c

[Eugene Teo <eugene.teo@eugeneteo.net>]

Pointer ax is dereferenced before NULL check.

Coverity bug #817

Signed-off-by: Eugene Teo <eugene.teo@eugeneteo.net>

--- linux-2.6/drivers/net/hamradio/mkiss.c~	2006-03-15 10:05:35.000000000 +0800
+++ linux-2.6/drivers/net/hamradio/mkiss.c	2006-03-16 14:31:35.000000000 +0800
@@ -844,13 +844,16 @@ static void mkiss_close(struct tty_struc
 static int mkiss_ioctl(struct tty_struct *tty, struct file *file,
 	unsigned int cmd, unsigned long arg)
 {
-	struct mkiss *ax = mkiss_get(tty);
-	struct net_device *dev = ax->dev;
+	struct mkiss *ax;
+	struct net_device *dev;
 	unsigned int tmp, err;
 
 	/* First make sure we're connected. */
 	if (ax == NULL)
 		return -ENXIO;
+	
+	ax = mkiss_get(tty);
+	dev = ax->dev;
 
 	switch (cmd) {
  	case SIOCGIFNAME:

-- 
1024D/A6D12F80 print D51D 2633 8DAC 04DB 7265  9BB8 5883 6DAA A6D1 2F80
main(i) { putchar(182623909 >> (i-1) * 5&31|!!(i<7)<<6) && main(++i); }

-
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