Commit a64d7894 authored Dec 09, 2019 by Thomas Hebb Committed by Greg Kroah-Hartman Jan 12, 2020

kconfig: don't crash on NULL expressions in expr_eq()



[ Upstream commit 272a72103012862e3a24ea06635253ead0b6e808 ]

NULL expressions are taken to always be true, as implemented by the
expr_is_yes() macro and by several other functions in expr.c. As such,
they ought to be valid inputs to expr_eq(), which compares two
expressions.

Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 17a6e26e

scripts/kconfig/expr.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -252,6 +252,13 @@ static int expr_eq(struct expr e1, struct expr e2)
		{
		int res, old_count;

		/*
		* A NULL expr is taken to be yes, but there's also a different way to
		* represent yes. expr_is_yes() checks for either representation.
		*/
		if (!e1 \|\| !e2)
		return expr_is_yes(e1) && expr_is_yes(e2);

		if (e1->type != e2->type)
		return 0;
		switch (e1->type) {