partway through its attempt to decode the result structure sent by
the server. If this happens, it can leave the result partially
populated with dynamically allocated memory. In this event, the
xdr_replymsg() failure is detected and RPC_CANTDECODERES is returned,
but the memory in the partially populated result struct is not
free()d.
The end result is that memory is leaked when an RPC_CANTDECODERES
error occurs. (This condition can occur if a CLIENT * handle is created
using clntudp_bufcreate() with a receive buffer size that is too small
to handle the result sent by the server.)
Fixed by setting reply_xdrs.x_op to XDR_FREE and calling
xdr_replymsg() again to free the memory if an RPC_CANTDECODERES error
is detected.
I suspect that the clnt_tcp.c, clnt_unix.c and clnt_raw.c modules
may ha a similar problem, but I haven't duplicated the condition with
those yet.
Found by: dbmalloc
This concludes tonight's entertainment. Once I'm sure I haven't destroyed
the world with all these changes, I'll import the utilities. Everything
should continue to work as before. If it doesn't let me know.
Special thanks to Mark Murray for running a test 'make world' for me to
shake out the bugs, which, hopefully, I have fixed.
(And there was much rejoicing.)
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
- fix timeout code
- better "random" initial transaction id for long running daemons
- unlimited number of file descriptors to select().
- 64 bit type safe wire protocol
Obtained from: a diff of FreeBSD vs. OpenBSD/NetBSD rpc code.
- typo (spelling police :-)
- dont die on select() that returns time remaining (on my systems)
1. Added missing function prototypes.
2. Added missing function return types.
3. Added missing function argument types.
4. Added missing headers for system function prototypes.
5. Corrected casts in select() args.
6. Got rid of more "extern int errno" rubbish.
7. Added extra parentheses around assignment used as truth value.
8. Fixed bug in clnt_{tcp, udp}create() where pointers could be free'd
even if they hadn't been successfully malloc()'d.
but a commit mail got lost, it's the same as for this commit:
lib/libc/gen confstr.c crypt.c disklabel.c fstab.c getcap.c
getgrent.c getgrouplist.c getpass.c getpwent.c
initgroups.c nlist.c psignal.c pwcache.c setmode.c
sleep.c sysconf.c sysctl.c syslog.c usleep.c
lib/libc/locale none.c read_runemagi.c setlocale.c
lib/libc/net gethostbydns.c getnetbydns.c getnetbynis.c
lib/libc/nls msgcat.c
lib/libc/quad Makefile.inc
lib/libc/regex engine.c regcomp.c regerror.c
Minor cleanup, mostly unused vars and missing #includes.
Limit the number of quad functions we pull in for 'i386'.
I still belive the quad stuff should go back into gcc.
Add compile-time warnings about crypt functions.
Back out the 'help NIS rebind faster' hack. This change used a
connect()/send() pair rather than the original sendto() to allow
RPC to pass ICMP host unreachable and similar errors up to RPC
programs that use UDP. This is not a terrible thing by itself, but it can
cause trouble in environments with multi-homed hosts: if the portmapper
on the multi-homed machine sends a reply with a source address
that's different than the one associated with the connection by
connect(), the kernel will send a port unreachable message and
drop the reply. For the sake of compatibility with everybody else
on the planet, it's best to revert to the old behavior.
*long, heavy sigh*
Obtained from: Casper H. Dik (by vay of Usenet)
Small patch to help improve NIS rebinding times (among other things):
>From: casper@fwi.uva.nl (Casper H.S. Dik)
>Newsgroups: comp.sys.sun.misc,comp.sys.sun.admin
>Subject: FIX for slow rebinding of NIS.
>Summary: a small change in libc makes life with NIS a lot easier.
>Message-ID: <1992Jan17.173905.11727@fwi.uva.nl>
>Date: 17 Jan 92 17:39:05 GMT
>Sender: news@fwi.uva.nl
>Organization: FWI, University of Amsterdam
>Lines: 138
>Nntp-Posting-Host: halo.fwi.uva.nl
Have you been plagued by long waits when your NIS server is rebooted?
READ ON!
Sun has a patch, but the README says:
********************* WARNING ******************************
This is a new version of ypbind that never uses the NIS
binding file to cache the servers binding. This will have
the effect of fixing the current symptom. However, it might
degrade the overall performance of the system when the
server is available. This is most likely to happen on an
overloaded server, which will cause the network to produce
a broadcast storm.
*************************************************************
Therefor, I have produced another fix.
o What goes wrong.
When the NIS server is rebooted, ypserv will obtain different ports
to listen for RPC requests. All clients will continue to use the old
binding they obtained earlier. The NIS server will send ICMP dst unreachable
messages for the RPC requests that arrive at the old port. These ICMPs
are dropped on the floor and the client code will continue sending the
requests until the timer has expired. The small fix at the end of this
message will pick up these ICMP messages and deliver them to the RPC layer.
o Before and after.
I've tested this on some machines and this is the result:
(kill and restart ypserv on the server)
original% time ypmatch user passwd
user:....
0.040u 0.090s 2:35.64 0.0% 0+126k 0+0io 0pf+0w (155 seconds elapsed time)
fixedhost% time ypmatch user passwd
user:....
0.050u 0.050s 0:10.20 0.9% 0+136k 0+0io 0pf+0w (10 seconds elapsed time)
Rebinding is almost instantaneous.
o Other benefits.
RPC calls that use UDP as transport will no longer time out but
will abort much sooner. (E.g., the remote host is unreachable or
111/udp is filtered by an intermediate router)
