[PATCH] tune2fs: Fix overflow of interval check

[Kazuya Mio <k-mio@sx.jp.nec.com>]

Add the check of maximum check interval.
s_checkinterval is 32bit variable, so it cannot be set more than 2^32.

Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
---
 misc/tune2fs.c |    6 ++++++
 1 file changed, 6 insertions(+)
diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index bcada11..625866f 100644
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -1705,6 +1705,12 @@ retry_open:
 		printf(_("Setting reserved blocks gid to %lu\n"), resgid);
 	}
 	if (i_flag) {
+		if (interval >= (1ULL << 32)) {
+			com_err(program_name, 0,
+				_("interval between checks is too big (%lu)"),
+				interval);
+			exit(1);
+		}
 		sb->s_checkinterval = interval;
 		ext2fs_mark_super_dirty(fs);
 		printf(_("Setting interval between checks to %lu seconds\n"),