From: Karel Zak <kzak@redhat.com>
Date: Thu, 11 Jul 2024 12:15:44 +0000 (+0200)
Subject: cal: make sure day_in_week() does not overrun array size [coverity scan]
X-Git-Tag: v2.42-start~259^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=54ff6aff58a59ad50a77483786b209da25e1ed73;p=thirdparty%2Futil-linux.git

cal: make sure day_in_week() does not overrun array size [coverity scan]

It's very theoretical, but protect against this possibility.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/misc-utils/cal.c b/misc-utils/cal.c
index 89bce4051..1af95124c 100644
--- a/misc-utils/cal.c
+++ b/misc-utils/cal.c
@@ -1175,6 +1175,9 @@ static int day_in_week(const struct cal_control *ctl, int day,
 	static const int reform[] = { 0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4 };
 	static const int old[]    = { 5, 1, 0, 3, 5, 1, 3, 6, 2, 4, 0, 2 };
 
+	if (month > 0 && month - 1 >= (int) ARRAY_SIZE(old))
+		month = ARRAY_SIZE(old);	/* for sure */
+
 	if (year != ctl->reform_year + 1)
 		year -= month < MARCH;
 	else