Commit 4d137ab0 authored by Masahiro Yamada's avatar Masahiro Yamada
Browse files

kconfig: require a space after '#' for valid input 



Currently, when an input line starts with '#', (line + 2) is passed to
memcmp() without checking line[1].

It means that line[1] can be any arbitrary character. For example,
"#KCONFIG_FOO is not set" is accepted as valid input, functioning the
same as "# CONFIG_FOO is not set".

More importantly, this can potentially lead to a buffer overrun if
line[1] == '\0'. It occurs if the input only contains '#', as
(line + 2) points to an uninitialized buffer.

Check line[1], and skip the line if it is not a space.

Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
parent 61e3e3c2

scripts/kconfig/confdata.c

+2 −0
Original line number Diff line number Diff line
@@ -426,6 +426,8 @@ int conf_read_simple(const char *name, int def) 
		conf_lineno++;

		sym = NULL;

		if (line[0] == '#') {

			if (line[1] != ' ')

				continue;

			if (memcmp(line + 2, CONFIG_, strlen(CONFIG_)))

				continue;

			p = strchr(line + 2 + strlen(CONFIG_), ' ');