heres a simple patch for the -s stuff just using the same method as with -l :) --- netkit-base-0.10/ping/ping.c.orig Mon Dec 13 15:33:56 1999 +++ netkit-base-0.10/ping/ping.c Mon Dec 13 15:34:15 1999 @@ -302,6 +302,11 @@ options |= F_SO_DONTROUTE; break; case 's': /* size of packet to send */ + if (!am_i_root) { + (void)fprintf(stderr, + "ping: %s\n", strerror(EPERM)); + exit(2); + } datalen = atoi(optarg); if (datalen > MAXPACKET) { (void)fprintf(stderr, ------------------------------------- On Sat, 11 Dec 1999, Stephen White wrote: > Mike Ireton wrote: > > > i found that when u do a ping -s 65468 -R ANYIPADDRESS ( -R record > > > route) the system starts to print on the screen kernel dumps > > > , freezes complitely and after few secconds the system reboots. > > This can be 'fixed' (okay kludged around) by altering the > > #define MAXPACKET (65536 - 60 - 8)/* max packet size */ > > line in ping.c > > I've reduced it to 32K (32768) on my Linux 2.0.36 box, since that should > avoid all possible problems (air on the side of caution and all that). I > don't see users having any reason to need such large ping packets anyway > (other than for the purpose of local or remote exploits). > > For those using RedHat 5.2 I've made an SRPM and .i368 RPM containing my > new ping and they are avaiable via annon. ftp at > > ftp://ox.compsoc.net/users/swhite/ping/ > > You'll need to install with --force since the package reports the same > version as the normal redhat5.2 one so RPM thinks it's already > installed. > > It has also been suggested that ping could be patched to make '-s' only > available to root (like '-l' is), as an alternative solution. I haven't > tried this but it should be a fairly simple modification. > > Neither of these address the real problem in the kernel, but they do > mean that sysadmins can go on allowing users to run ping without the > worry of quite such a trivial DoS. > > The same problem does not appear to occur in Linux 2.2, Windows 95 or > Solaris 2.7. > > -- > Stephen White OU Compsoc System Administration Team > <swhiteat_private> http://www.ox.compsoc.net/~swhite/ >
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