diff options
| author | Jan Kara <jack@suse.cz> | 2018-04-12 17:22:23 +0200 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2018-04-18 16:34:55 +0200 |
| commit | 44f06ba8297c7e9dfd0e49b40cbe119113cca094 (patch) | |
| tree | 376c1b3c48c949da90bd7cfebd254d2f72d76e98 /fs/udf/unicode.c | |
| parent | 06856938112b84ff3c6b0594d017f59cfda2a43d (diff) | |
| download | lwn-44f06ba8297c7e9dfd0e49b40cbe119113cca094.tar.gz lwn-44f06ba8297c7e9dfd0e49b40cbe119113cca094.zip | |
udf: Fix leak of UTF-16 surrogates into encoded strings
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>
Diffstat (limited to 'fs/udf/unicode.c')
| -rw-r--r-- | fs/udf/unicode.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c index f897e55f2cd0..16a8ad21b77e 100644 --- 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) { |