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    SubjectRe: ping to broadcast address: permission denied?
    If you would have actually tried first to see if you could verify your
    claim, maybe you wouldn't have made such a fool of yourself.

    Observe:

    utopia:~$ ls -al /bin/ping
    -r-sr-xr-x 1 root bin 17412 Feb 18 1995 /bin/ping
    utopia:~$ ifconfig eth0
    eth0 Link encap:10Mbps Ethernet HWaddr 00:00:C0:F0:75:0E
    inet addr:206.84.74.11 Bcast:206.84.74.255 Mask:255.255.255.0
    UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
    RX packets:0 errors:927673 dropped:0 overruns:0
    TX packets:0 errors:0 dropped:620623 overruns:2
    (yeah ill upgrade ifconfig sometime :)
    Interrupt:10 Base address:0x6000

    utopia:~$ ping 206.84.74.255
    PING 206.84.74.255 (206.84.74.255): 56 data bytes
    ping: sendto: Permission denied
    ping: wrote 206.84.74.255 64 chars, ret=-1
    ping: sendto: Permission denied
    ping: wrote 206.84.74.255 64 chars, ret=-1

    --- 206.84.74.255 ping statistics ---
    2 packets transmitted, 0 packets received, 100% packet loss

    Obviously this is running as root...
    And pinging the broadcast address is still failing...
    Any network gurus know why?

    PS
    Maybe you could have noticed his '#' prompt... sure, thats doesn't
    necessarily imply that he is root, but its usually the case.

    On Fri, 7 Mar 1997, Bryn Paul Arnold Jones wrote:

    > On Fri, 7 Mar 1997, Paul Slootman wrote:
    >
    > > Niemi@linux.wauug.org wrote:
    > > >
    > > >I have fetched, compiled, and made available Trygve Gudmundsen's
    > > >Linux-modified version of Eric Wassenaar's excellent "ping" program. It is
    > > >all sitting on on wauug.erols.com in "/pub/net/wassenaar-ping". As Trygve
    > > >mentioned his site was about to be down for 5 days I figured this could be
    > > >a useful service 8^)
    > >
    > > I've picked up this version, compiled it, but it still doesn't
    > > do what I'd hoped (I had already expected it wasn't a ping code
    > > problem).
    > >
    > > The problem is this:
    > >
    > > I'm on a subnetted B-class network (141.93.34.0, netmask 255.255.255.0).
    > > This all works fine, however I cannot ping the broadcast address (which
    > > is 141.93.34.255). Ping says:
    > >
    > > # ./ping 141.93.34.255
    > > PING 141.93.34.255: 56 data bytes
    > > sendto: Permission denied
    > > no reply from 141.93.34.255 within 1 sec
    > > sendto: Permission denied
    > >
    > > ---- 141.93.34.255 PING Statistics ----
    > > 2 packets transmitted, 0 packets received, 100% packet loss
    > >
    >
    > This would be a setuid root problem, ie it isn't. Does it work if you run
    > the binary as root ?
    >
    > > This works perfectly from a Solaris 2.5 system on the same network...
    > > I tried tracing this into the kernel, but at a certain point I get
    > > lost. It's definitely sendto() that returns -1 EACCES, according to
    > > strace.
    > >
    >
    > Yep, the solaris binary will be setuid root.
    >
    > > Same thing when pinging the loopback broadcast address 127.255.255.255,
    > > so it doesn't look like it's a subnetting problem.
    > >
    >
    > Try setting the setuid bit on the binary:
    >
    > chown root.root ping; chmod 4555 ping
    >
    > It should now look like:
    >
    > -r-sr-xr-x 1 root root 12272 Jan 31 22:32 ping*
    > ^ setuid bit.
    >
    > > Anyone know what the problem is? Even better, what the solution is?
    > > Vanilla 2.0.29.
    > >
    > >
    > > Paul Slootman
    > > --
    > Bryn
    > --
    > PGP key pass phrase forgotten, \ Overload -- core meltdown sequence
    > again :( and I don't care ;) | initiated.
    > / This space is intentionally left
    > | blank, apart from this text ;-)
    > \____________________________________
    >


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