linux - tools/objtool/tests/generic/test-init-reference.sh

29 lines · 1.1 KiB

1	#!/bin/bash
2	# SPDX-License-Identifier: GPL-2.0
3	#
4	# Init code and data are freed after boot, so a klp relocation against them can
5	# never resolve. Such a patch must be rejected.
6
7	. "$(dirname "$0")/../lib.sh"
8
9	setup
10	build_pair init_reference.c
11
12	# The rejection can only happen if the patched build really does reference the
13	# init symbol. The fixture makes init_only volatile so the read cannot be
14	# folded away, and this checks that it worked: without a relocation klp diff
15	# would succeed, and the failure below would read as a missing check rather
16	# than as a fixture which stopped posing the question.
17	# Either spelling will do. A file-local variable is reached through its
18	# section symbol -- .init.data -- and a global one by name; which of the two
19	# the compiler picks is its business, and the reference is what matters.
20	in_relocs "$patched_obj" \|
21	awk '$5 == ".init.data" \|\| $5 == "init_only"' \| grep -q . \|\|
22	fail "patched object has no reference into .init.data; the fixture tests nothing"
23
24	run_diff 255
25
26	diff_log \| grep -q "can't patch or reference init code/data" \|\|
27	fail "expected rejection, got: $(diff_log \| tail -1)"
28
29	pass "reference to init data rejected"