#1381 broken pipe cause snmptrapd to exit

[Anonymous]

If snmptrapd runs a traphandle and recive a SIGPIPE
(broken pipe) the daemon exits without an error.

<snip src="strace">
--- SIGCHLD (Child exited) ---
close(9) = 0
close(12) = 0
write(10, "hostname\nxxx.xxx.xxx.xxx\nS"..., 357) = -1
EPIPE (Broken pipe)
--- SIGPIPE (Broken pipe) ---
</snip>

You can reproduce this using /bin/true as traphandle
program.

There is no error in the logfile and all seems
completly OK, only that the snmptrapd is not runing any
more :-(

An error message and an runing snmptrapd seems for me
more reliable.

My email address is ak@ilk.net

net-snmp version: 5.1.2

[Thomas Anders]

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user_id=848638

This should be fixed in 5.1.3.pre1 and a patch has been
posted on the mailinglists. It basically involves to ignore
SIGPIPE.

[Thomas Anders]

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Can you please indicate whether 5.1.3.pre1 and/or the
addition of "signal(SIGPIPE, SIG_IGN)" fixes your problem?
We tend to think that this issue is already solved and the
bug should be closed.

[Nobody/Anonymous]

Logged In: NO

I did an test on my FreeBSD box.

$ snmptrapd -v

NET-SNMP Version: 5.2.1
Web: http://www.net-snmp.org/
Email: net-snmp-coders@lists.sourceforge.net

Strace on pid.

pipe([11, 12]) = 11
pipe([13, 14]) = 13
fork() = 67259
close(11) = 0
--- SIGCHLD (Child exited) ---
close(14) = 0
write(12, "localhost\nUDP: [127.0.0.1]:54936"..., 290) = -1
EPIPE (Broken pipe)
--- SIGPIPE (Broken pipe) ---
--- SIGPIPE (Broken pipe) ---
$ ps aux|grep snmp
$

As trap I send:

$ snmptrap -v 1 -c public localhost '' '' 3 0 ''

Btw, an logentry would be nicer ;-)

[Thomas Anders]

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user_id=848638

5.2.1 does *not* have the fix. You either need to use
5.1.3.pre1 or CVS (they all have the fix) or add
"signal(SIGPIPE, SIG_IGN)" around line 1128 in the 5.2.1
source of apps/snmptrapd.c manually.

[Thomas Anders]

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user_id=848638

As this is already fixed in CVS, I'm closing the bug.