[Q] attr.c bug?

["Alex Zeltser" <alex_zeltser@securecomputing.com>]

Just came across something that seemed strange.  I'm doing some testing
with the NT port of slapd.  In attr.c, in attr_syntax_config the variable
'at' is allocated with a call to ch_calloc.  In the case of an error it is
freed a few lines later with a call to free; in the case of no error, it is
freed at the end of the function with ldap_memfree (which in turn calls
ber_memfree).  Looking at implementations of ch_calloc and ber_memfree, it
appears that the two are not compatible.  It seems ok to call free on a
ch_calloc'ed ptr, but not ber_memfree.  In my case, this triggered an
assert.  Has  noone else run into this?  (It seems that the use of three
potentially different memory management functions on the same pointer is a
little risky, or is it just me?)

(As an aside, why does attr_syntax_config even need to alloc at off the
heap, if it's always freed upon function exit?  Why not just declare it as
a stack variable and be done with it?  Am I missing something?)

(As another aside, are ch_xalloc functions meant to only be used for
allocations that _must_ succeed for the program to function properly?  They
all see to call 'exit' on allocation failures which seems a bit extreme
under normal conditions.)

Thanks,

Alex Zeltser