Commit d09b8fa1 authored May 24, 2014 by Michael Tokarev

libcacard: fix wrong array expansion logic



The currrent code in libcacard/vcard_emul_nss.c:vcard_emul_options()
has a weird bug in variable usage around expanding opts->vreader
array.

There's a helper variable, vreaderOpt, which is first needlessly
initialized to NULL, next, conditionally, only we have to expand
opts->vreader, receives array expansion from g_renew(), and next,
even if we don't actually perform expansion, the value of this
variable is assigned to the actual array, opts->vreader, which
was supposed to be expanded.

So, since we expand the array by READER_STEP increments, only
once in READER_STEP (=4) the code will work, in other 3/4 times
it will fail badly.

Fix this by not using this temp variable when expanding the
array, and by dropping the useless =NULL initializer too -
if it wasn't in place initially, compiler would have warned
us about this problem at the beginning.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Markus Armbruster <armbru@redhat.com>

parent 42119fa3

libcacard/vcard_emul_nss.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -1149,7 +1149,7 @@ vcard_emul_options(const char *args)
		char type_str[100];
		VCardEmulType type;
		int count, i;
		VirtualReaderOptions *vreaderOpt = NULL;
		VirtualReaderOptions *vreaderOpt;

		args = strip(args + 5);
		if (*args != '(') {
		@@ -1173,11 +1173,10 @@ vcard_emul_options(const char *args)

		if (opts->vreader_count >= reader_count) {
		reader_count += READER_STEP;
		vreaderOpt = g_renew(VirtualReaderOptions, opts->vreader,
		opts->vreader = g_renew(VirtualReaderOptions, opts->vreader,
		reader_count);
		}
		opts->vreader = vreaderOpt;
		vreaderOpt = &vreaderOpt[opts->vreader_count];
		vreaderOpt = &opts->vreader[opts->vreader_count];
		vreaderOpt->name = g_strndup(name, name_length);
		vreaderOpt->vname = g_strndup(vname, vname_length);
		vreaderOpt->card_type = type;