| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.4 326/411] modpost: fix removing numeric suffixes | Date | Mon, 13 Jun 2022 12:09:59 +0200 |
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From: Alexander Lobakin <alexandr.lobakin@intel.com>
[ 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@intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- 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 13cda6aa2688..74e2052f429d 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1998,7 +1998,7 @@ 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; } return s; -- 2.35.1
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