| From 44f06ba8297c7e9dfd0e49b40cbe119113cca094 Mon Sep 17 00:00:00 2001 |
| From: Jan Kara <jack@suse.cz> |
| Date: Thu, 12 Apr 2018 17:22:23 +0200 |
| Subject: udf: Fix leak of UTF-16 surrogates into encoded strings |
| |
| From: Jan Kara <jack@suse.cz> |
| |
| commit 44f06ba8297c7e9dfd0e49b40cbe119113cca094 upstream. |
| |
| OSTA UDF specification does not mention whether the CS0 charset in case |
| of two bytes per character encoding should be treated in UTF-16 or |
| UCS-2. The sample code in the standard does not treat UTF-16 surrogates |
| in any special way but on systems such as Windows which work in UTF-16 |
| internally, filenames would be treated as being in UTF-16 effectively. |
| In Linux it is more difficult to handle characters outside of Base |
| Multilingual plane (beyond 0xffff) as NLS framework works with 2-byte |
| characters only. Just make sure we don't leak UTF-16 surrogates into the |
| resulting string when loading names from the filesystem for now. |
| |
| CC: stable@vger.kernel.org # >= v4.6 |
| Reported-by: Mingye Wang <arthur200126@gmail.com> |
| Signed-off-by: Jan Kara <jack@suse.cz> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| fs/udf/unicode.c | 6 ++++++ |
| 1 file changed, 6 insertions(+) |
| |
| --- a/fs/udf/unicode.c |
| +++ b/fs/udf/unicode.c |
| @@ -28,6 +28,9 @@ |
| |
| #include "udf_sb.h" |
| |
| +#define SURROGATE_MASK 0xfffff800 |
| +#define SURROGATE_PAIR 0x0000d800 |
| + |
| static int udf_uni2char_utf8(wchar_t uni, |
| unsigned char *out, |
| int boundlen) |
| @@ -37,6 +40,9 @@ static int udf_uni2char_utf8(wchar_t uni |
| if (boundlen <= 0) |
| return -ENAMETOOLONG; |
| |
| + if ((uni & SURROGATE_MASK) == SURROGATE_PAIR) |
| + return -EINVAL; |
| + |
| if (uni < 0x80) { |
| out[u_len++] = (unsigned char)uni; |
| } else if (uni < 0x800) { |
