blob: ac08be515bf109b8be1b5fddd1c04799908e57d4 [file] [log] [blame]
From 2eaea70111f65b16d55998386e4ceb4273c19eb4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20G=C3=B6ttsche?= <cgzones@googlemail.com>
Date: Fri, 31 Mar 2023 14:46:50 +0200
Subject: [PATCH] Overhaul valid_field()
e5905c4b ("Added control character check") introduced checking for
control characters but had the logic inverted, so it rejects all
characters that are not control ones.
Cast the character to `unsigned char` before passing to the character
checking functions to avoid UB.
Use strpbrk(3) for the illegal character test and return early.
Upstream-Status: Backport [https://github.com/shadow-maint/shadow/commit/2eaea70111f65b16d55998386e4ceb4273c19eb4]
Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
---
lib/fields.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/lib/fields.c b/lib/fields.c
index fb51b582..53929248 100644
--- a/lib/fields.c
+++ b/lib/fields.c
@@ -37,26 +37,22 @@ int valid_field (const char *field, const char *illegal)
/* For each character of field, search if it appears in the list
* of illegal characters. */
+ if (illegal && NULL != strpbrk (field, illegal)) {
+ return -1;
+ }
+
+ /* Search if there are non-printable or control characters */
for (cp = field; '\0' != *cp; cp++) {
- if (strchr (illegal, *cp) != NULL) {
+ unsigned char c = *cp;
+ if (!isprint (c)) {
+ err = 1;
+ }
+ if (iscntrl (c)) {
err = -1;
break;
}
}
- if (0 == err) {
- /* Search if there are non-printable or control characters */
- for (cp = field; '\0' != *cp; cp++) {
- if (!isprint (*cp)) {
- err = 1;
- }
- if (!iscntrl (*cp)) {
- err = -1;
- break;
- }
- }
- }
-
return err;
}
--
2.34.1