net: tcp_probe: adapt tbuf size for recent changes

Daniel Borkmann · davem330 · commit cc8c6c1b21c9 · 2013-09-04T00:27:28.000-04:00
With recent changes in tcp_probe module (e.g. f925d0a ("net: tcp_probe: add IPv6 support")) we also need to take into account that tbuf needs to be updated as format string will be further expanded. tbuf sits on the stack in tcpprobe_read() function that is invoked when user space reads procfs file /proc/net/tcpprobe, hence not fast path as in jtcp_rcv_established(). Having a size similarly as in sctp_probe module of 256 bytes is fully sufficient for that, we need theoretical maximum of 252 bytes otherwise we could get truncated. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_probe.c b/net/ipv4/tcp_probe.c
@@ -218,7 +218,7 @@ static ssize_t tcpprobe_read(struct file *file, char __user *buf,
 		return -EINVAL;
 
 	while (cnt < len) {
-		char tbuf[164];
+		char tbuf[256];
 		int width;
 
 		/* Wait for data in buffer */
