msm: ipa: Fix string out of bound issue.

Currently during RMNET_IOCTL_GET_MTU and RMNET_IOCTL_SET_MTU ioctls
we can recieve not null terminated string for if_name which was
resulting in string out of bound error while accessing the if_name.
Now adding null character at the end of string to prevent access
beyond its size.

Change-Id: I4d82a4b491f04a85d6ab4f0211671520156f7c61
Signed-off-by: Piyush Dhyani <[email protected]>

drivers/platform/msm/ipa/ipa_v3/rmnet_ipa.c

@@ -3029,6 +3029,8 @@ static int ipa3_wwan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 		/* Get MTU */
 		case RMNET_IOCTL_GET_MTU:
 			mux_channel = rmnet_ipa3_ctx->mux_channel;
+			ext_ioctl_data.u.mtu_params.if_name
+				[IFNAMSIZ-1] = '\0';
 			rmnet_index =
 				find_vchannel_name_index(ext_ioctl_data.u.mtu_params.if_name);
 
@@ -3049,6 +3051,8 @@ static int ipa3_wwan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 		/* Set MTU */
 		case RMNET_IOCTL_SET_MTU:
 			mux_channel = rmnet_ipa3_ctx->mux_channel;
+			ext_ioctl_data.u.mtu_params.if_name
+				[IFNAMSIZ-1] = '\0';
 			rmnet_index =
 				find_vchannel_name_index(ext_ioctl_data.u.mtu_params.if_name);