From fe14f880500cd842eadd581b7261538bb9646b7f Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt 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 --- 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; }