From: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> [ Upstream commit b5beffa20d83c4e15306c991ffd00de0d8628338 ] With the `-z unique-symbol` linker flag or any similar mechanism, it is possible to trigger the following: ERROR: modpost: "param_set_uint.0" [vmlinux] is a static EXPORT_SYMBOL The reason is that for now the condition from remove_dot(): if (m && (s[n + m] == '.' || s[n + m] == 0)) which was designed to test if it's a dot or a '\0' after the suffix is never satisfied. This is due to that `s[n + m]` always points to the last digit of a numeric suffix, not on the symbol next to it (from a custom debug print added to modpost): param_set_uint.0, s[n + m] is '0', s[n + m + 1] is '\0' So it's off-by-one and was like that since 2014. Fix this for the sake of any potential upcoming features, but don't bother stable-backporting, as it's well hidden -- apart from that LD flag, it can be triggered only with GCC LTO which never landed upstream. Fixes: fcd38ed0ff26 ("scripts: modpost: fix compilation warning") Signed-off-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> Reviewed-by: Petr Mladek <pmladek@xxxxxxxx> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- scripts/mod/modpost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index e04ae56931e2..3b098e26938e 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1986,7 +1986,7 @@ static char *remove_dot(char *s) if (n && s[n]) { size_t m = strspn(s + n + 1, "0123456789"); - if (m && (s[n + m] == '.' || s[n + m] == 0)) + if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0)) s[n] = 0; /* strip trailing .lto */ -- 2.35.1