From 61ed3913790901f2ad4973de60b373150fde01e0 Mon Sep 17 00:00:00 2001
From: Jan Synacek <jsynacek@redhat.com>
Date: Wed, 20 Apr 2016 09:51:12 +0200
Subject: [PATCH] ping: do not allow oversized packets to root

The code later fails anyways (as the original comment suggests), which
results in a weird recvmsg() loop that times out eventually.

Reproducer:

./ping -c 1 -s 65530 127.0.0.1
---
 ping.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/ping.c b/ping.c
index f435fe2..ea37c4f 100644
--- a/ping.c
+++ b/ping.c
@@ -80,8 +80,6 @@ ping_func_set_st ping4_func_set = {
 #define	NROUTES		9		/* number of record route slots */
 #define TOS_MAX		255		/* 8-bit TOS field */
 
-static const int max_ping4_packet = 0x10000;
-
 static int ts_type;
 static int nroute = 0;
 static __u32 route[10];
@@ -806,12 +804,8 @@ int ping4_run(int argc, char **argv, struct addrinfo *ai, socket_st *sock)
 	}
 
 	if (datalen > 0xFFFF - 8 - optlen - 20) {
-		if (uid || datalen > max_ping4_packet-8 || datalen > MAXPACKET-8) {
-			fprintf(stderr, "Error: packet size %d is too large. Maximum is %d\n", datalen, 0xFFFF-8-20-optlen);
-			exit(2);
-		}
-		/* Allow small oversize to root yet. It will cause EMSGSIZE. */
-		fprintf(stderr, "WARNING: packet size %d is too large. Maximum is %d\n", datalen, 0xFFFF-8-20-optlen);
+		fprintf(stderr, "Error: packet size %d is too large. Maximum is %d\n", datalen, 0xFFFF-8-20-optlen);
+		exit(2);
 	}
 
 	if (datalen >= sizeof(struct timeval))	/* can we time transfer */
-- 
2.7.4