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: f3462aa9 ("Kbuild: Handle longer symbols in kallsyms.c")
Signed-off-by: NEugene Loh <eugene.loh@oracle.com>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>

scripts/kallsyms.c

@@ -120,8 +120,8 @@ static int read_symbol(FILE *in, struct sym_entry *s)
 			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;