From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Fri, 7 Jun 2019 10:29:24 +0000 (+0200)
Subject: passwd: do not set 0 as date of last password change, closes 11951
X-Git-Tag: 1_31_0~15
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=a5c5dc6f0b96f9ef8c567f40388d91d44aec1eb7;p=oweals%2Fbusybox.git

passwd: do not set 0 as date of last password change, closes 11951

function                                             old     new   delta
update_passwd                                       1491    1505     +14

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---

diff --git a/libbb/update_passwd.c b/libbb/update_passwd.c
index 95423d19b..dc967683a 100644
--- a/libbb/update_passwd.c
+++ b/libbb/update_passwd.c
@@ -270,10 +270,16 @@ int FAST_FUNC update_passwd(const char *filename,
 			if (shadow && *cp == ':') {
 				/* /etc/shadow's field 3 (passwd change date) needs updating */
 				/* move past old change date */
+				unsigned time_days = (unsigned long)(time(NULL)) / (24*60*60);
+
+				if (time_days == 0) {
+					/* 0 as change date has special meaning, avoid it */
+					time_days = 1;
+				}
 				cp = strchrnul(cp + 1, ':');
 				/* "name:" + "new_passwd" + ":" + "change date" + ":rest of line" */
 				fprintf(new_fp, "%s%s:%u%s\n", name_colon, new_passwd,
-					(unsigned)(time(NULL)) / (24*60*60), cp);
+					time_days, cp);
 			} else {
 				/* "name:" + "new_passwd" + ":rest of line" */
 				fprintf(new_fp, "%s%s%s\n", name_colon, new_passwd, cp);