b43: N-PHY: handle allocation fail in samples generation

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/b43/phy_n.c b/drivers/net/wireless/b43/phy_n.c
index 074b34c..795bb1e 100644
--- a/drivers/net/wireless/b43/phy_n.c
+++ b/drivers/net/wireless/b43/phy_n.c
@@ -1069,6 +1069,10 @@
 	}
 
 	samples = kzalloc(len * sizeof(struct b43_c32), GFP_KERNEL);
+	if (!samples) {
+		b43err(dev->wl, "allocation for samples generation failed\n");
+		return 0;
+	}
 	rot = (((freq * 36) / bw) << 16) / 100;
 	angle = 0;