multipath-tools-0.5.0 segfault with blacklist/blacklist_exceptions

[Brian De Wolf <bldewolf@cpp.edu>]

Hello,

I was upgrading multipath-tools and noticed our old config causes the
various programs to segfault in libmultipath.  The culprit appeared to
be our blacklist entries with a vendor listed but no product (for
filtering the local disk controllers), e.g:

	blacklist {
		device {
			vendor "LSILOGIC"
		}
	}

Adding a product of .* makes things work as expected, but this
shouldn't be necessary.  It looks like this is because compiling the
product regex is optional:

http://git.opensvc.com/gitweb.cgi?p=multipath-tools/.git;a=blob;f=libmultipath/blacklist.c;h=3f9e80b6bf92502ce01a4a287d17039a1ad9c2ce;hb=HEAD#l89

But the regexec is not:

http://git.opensvc.com/gitweb.cgi?p=multipath-tools/.git;a=blob;f=libmultipath/blacklist.c;h=3f9e80b6bf92502ce01a4a287d17039a1ad9c2ce;hb=HEAD#l151

I couldn't find any posts about this and it didn't look fixed yet,
so I figured I should report the issue.