lib: packing: catch kunit_kzalloc() failure in the pack() test

JIRA: https://issues.redhat.com/browse/RHEL-92666

Upstream commit(s):
commit 1405981
Author: Vladimir Oltean <vladimir.oltean@nxp.com>
Date:   Fri Oct 4 14:00:12 2024 +0300

    lib: packing: catch kunit_kzalloc() failure in the pack() test

    kunit_kzalloc() may fail. Other call sites verify that this is the case,
    either using a direct comparison with the NULL pointer, or the
    KUNIT_ASSERT_NOT_NULL() or KUNIT_ASSERT_NOT_ERR_OR_NULL().

    Pick KUNIT_ASSERT_NOT_NULL() as the error handling method that made most
    sense to me. It's an unlikely thing to happen, but at least we call
    __kunit_abort() instead of dereferencing this NULL pointer.

    Fixes: e9502ea ("lib: packing: add KUnit tests adapted from selftests")
    Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
    Link: https://patch.msgid.link/20241004110012.1323427-1-vladimir.oltean@nxp.com
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Signed-off-by: Petr Oros <poros@redhat.com>

Author: orosp

lib/packing_test.c

@@ -375,6 +375,7 @@ static void packing_test_pack(struct kunit *test)
 	int err;
 
 	pbuf = kunit_kzalloc(test, params->pbuf_size, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, pbuf);
 
 	err = pack(pbuf, params->uval, params->start_bit, params->end_bit,
 		   params->pbuf_size, params->quirks);