6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masahiro Yamada <masahiroy@xxxxxxxxxx>
[ Upstream commit 4d137ab0107ead0f2590fc0314e627431e3b9e3f ]
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: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Stable-dep-of: a409fc1463d6 ("kconfig: fix memory leak in sym_warn_unmet_dep()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
scripts/kconfig/confdata.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index 02ac250b8fe9e..8694ab1e04067 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -432,6 +432,8 @@ 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_), ' ');
--
2.39.5
