From fe14f880500cd842eadd581b7261538bb9646b7f Mon Sep 17 00:00:00 2001
From: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Date: Sat, 29 Jan 2022 16:43:20 +0100
Subject: [PATCH] lib: fix snprintf() for UTF-16 strings
snprintf() must return the required buffer length.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
---
lib/vsprintf.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 69b2f6a1ad..fe06aa2d71 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -285,15 +285,25 @@ static __maybe_unused char *string16(char *buf, char *end, u16 *s,
if (!(flags & LEFT))
for (; len < field_width; --field_width)
ADDCH(buf, ' ');
- for (i = 0; i < len && buf + utf16_utf8_strnlen(str, 1) <= end; ++i) {
+ if (buf < end)
+ *buf = 0;
+ for (i = 0; i < len; ++i) {
+ int slen = utf16_utf8_strnlen(str, 1);
s32 s = utf16_get(&str);
if (s < 0)
s = '?';
- utf8_put(s, &buf);
+ if (buf + slen < end) {
+ utf8_put(s, &buf);
+ if (buf < end)
+ *buf = 0;
+ } else {
+ buf += slen;
+ }
}
for (; len < field_width; --field_width)
ADDCH(buf, ' ');
+
return buf;
}
--
2.39.5