| Message ID | 20231118075912.1303509-1-masahiroy@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/6] kconfig: require a space after '#' for valid input | expand |
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c index 2ba4dfdd1aee..556b7f087dbb 100644 --- a/scripts/kconfig/confdata.c +++ b/scripts/kconfig/confdata.c @@ -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_), ' ');
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@kernel.org> --- scripts/kconfig/confdata.c | 2 ++ 1 file changed, 2 insertions(+)