mISDN: Remove VLAs

There's an ongoing effort to remove VLAs[1] from the kernel to eventually
turn on -Wvla. Remove the VLAs from the mISDN code by switching to using
kstrdup in one place and using an upper bound in another.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/mISDN/dsp_hwec.c

@@ -68,12 +68,12 @@ void dsp_hwec_enable(struct dsp *dsp, const char *arg)
 		goto _do;
 
 	{
-		char _dup[len + 1];
 		char *dup, *tok, *name, *val;
 		int tmp;
 
-		strcpy(_dup, arg);
-		dup = _dup;
+		dup = kstrdup(arg, GFP_ATOMIC);
+		if (!dup)
+			return;
 
 		while ((tok = strsep(&dup, ","))) {
 			if (!strlen(tok))
@@ -89,6 +89,8 @@ void dsp_hwec_enable(struct dsp *dsp, const char *arg)
 					deftaps = tmp;
 			}
 		}
+
+		kfree(dup);
 	}
 
 _do: