Subject: bin/10047: amd with hesiod maps sometimes crashing
To: None <email@example.com>
From: Mark Davies <mark@MCS.VUW.AC.NZ>
Date: 05/04/2000 17:18:12
>Synopsis: amd with hesiod maps sometimes crashing
>Arrival-Date: Thu May 04 17:19:01 PDT 2000
>Originator: Mark Davies
Dept. of Comp. Sci., Victoria Uni. of Wellington, New Zealand.
System: NetBSD city-art.mcs.vuw.ac.nz 1.4X NetBSD 1.4X (MCS_WORKSTATION) #0: Sun Apr 9 10:29:55 NZST 2000 firstname.lastname@example.org:/src/build/src/sys/arch/i386/compile/MCS_WORKSTATION i386
amd will sometimes coredump when using hesiod maps when looking up
keys that start with a "."
Below is what I sent to the amd and hesiod developers about a year ago when I
first discovered this problem on Digital UNIX. The versions in NetBSD still
have the problem.
This is actually a hesiod bug but it makes amd core dump.
a call to hesiod_resolve in the "new style hesiod" (version 3.0.2 at least)
with a key of the form ".directory.others.u", or any key with a leading "."
returns NULL but _errno has value 0_.
The effect of this on amd is that under these circumstances hesiod_search will
not set pval but mapc_meta_search which calls it will assume that it has (due
to the lack of an positive errno) and will try to dereference it.
I started seeing this happen a lot once we started running KDE which tends to
want to look for the file ".directory" in every directory the file manager
My workaround is below:
*** info_hesiod.c~ Thu Feb 4 20:24:15 1999
--- info_hesiod.c Wed Mar 10 13:30:24 1999
*** 107,112 ****
--- 107,115 ----
(unsigned long) m, map, key, (unsigned long) pval, (unsigned long) tp);
#endif /* DEBUG */
+ if (key == '.')
+ return ENOENT;
sprintf(hes_key, "%s.%s", key, map + HES_PREFLEN);
On the assumption that a key with a leading "." is never valid in a hesiod