From: Jan Kara Date: Wed, 21 Jun 2023 09:32:35 +0000 (+0200) Subject: udf: Fix uninitialized array access for some pathnames X-Git-Tag: v4.14.324~51 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=008ae78d1e12efa904dc819b1ec83e2bca6b2c56;p=thirdparty%2Fkernel%2Fstable.git udf: Fix uninitialized array access for some pathnames [ Upstream commit 028f6055c912588e6f72722d89c30b401bbcf013 ] For filenames that begin with . and are between 2 and 5 characters long, UDF charset conversion code would read uninitialized memory in the output buffer. The only practical impact is that the name may be prepended a "unification hash" when it is not actually needed but still it is good to fix this. Reported-by: syzbot+cd311b1e43cc25f90d18@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/000000000000e2638a05fe9dc8f9@google.com Signed-off-by: Jan Kara Signed-off-by: Sasha Levin --- diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c index 61a1738895b7a..ad04dc2278339 100644 --- a/fs/udf/unicode.c +++ b/fs/udf/unicode.c @@ -268,7 +268,7 @@ static int udf_name_from_CS0(uint8_t *str_o, int str_max_len, } if (translate) { - if (str_o_len <= 2 && str_o[0] == '.' && + if (str_o_len > 0 && str_o_len <= 2 && str_o[0] == '.' && (str_o_len == 1 || str_o[1] == '.')) needsCRC = 1; if (needsCRC) {