kallsyms: Handle too long symbols in kallsyms.c

[ Upstream commit 6db2983cd8064808141ccefd75218f5b4345ffae ]

When checking for symbols with excessively long names,
account for null terminating character.

Fixes: f3462aa952cf ("Kbuild: Handle longer symbols in kallsyms.c")
Signed-off-by: Eugene Loh <eugene.loh@oracle.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index a9186a9..0c9c54b 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -120,8 +120,8 @@
 			fprintf(stderr, "Read error or end of file.\n");
 		return -1;
 	}
-	if (strlen(sym) > KSYM_NAME_LEN) {
-		fprintf(stderr, "Symbol %s too long for kallsyms (%zu vs %d).\n"
+	if (strlen(sym) >= KSYM_NAME_LEN) {
+		fprintf(stderr, "Symbol %s too long for kallsyms (%zu >= %d).\n"
 				"Please increase KSYM_NAME_LEN both in kernel and kallsyms.c\n",
 			sym, strlen(sym), KSYM_NAME_LEN);
 		return -1;