fs: udf: parse_options: blocksize check

Both affs and isofs check for blocksize integrity during
parse_options.Do the same thing for udf.

Valid values : 512, 1024, 2048 or 4096 bytes.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 5 insertions, 1 deletions

diff --git a/fs/udf/super.c b/fs/udf/super.c
index 3306b9f69bed..ac765386004e 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -505,6 +505,7 @@ static int udf_parse_options(char *options, struct udf_options *uopt,
         while ((p = strsep(&options, ",")) != NULL) {
                 substring_t args[MAX_OPT_ARGS];
                 int token;
+                unsigned n;
                 if (!*p)
                         continue;
 
@@ -516,7 +517,10 @@ static int udf_parse_options(char *options, struct udf_options *uopt,
                 case Opt_bs:
                         if (match_int(&args[0], &option))
                                 return 0;
-                        uopt->blocksize = option;
+                        n = option;
+                        if (n != 512 && n != 1024 && n != 2048 && n != 4096)
+                                return 0;
+                        uopt->blocksize = n;
                         uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
                         break;
                 case Opt_unhide: