From: BingJing Chang <[email protected]>

If uid or gid of mount options is larger than INT_MAX, isofs_fill_super
will return -EINVAL.

The problem can be encountered by a domain user or reproduced via:
mount -o loop,uid=2147483648 ubuntu-16.04.6-server-amd64.iso /mnt

This can be fixed as commit 233a01fa9c4c ("fuse: handle large user and
group ID").

Reviewed-by: Robbie Ko <[email protected]>
Reviewed-by: Chung-Chiang Cheng <[email protected]>
Signed-off-by: BingJing Chang <[email protected]>
---
 fs/isofs/inode.c | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index ec90773..342ac19 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -335,10 +335,23 @@ static const match_table_t tokens = {
        {Opt_err, NULL}
 };
 
+static int isofs_match_uint(substring_t *s, unsigned int *res)
+{
+       int err = -ENOMEM;
+       char *buf = match_strdup(s);
+
+       if (buf) {
+               err = kstrtouint(buf, 10, res);
+               kfree(buf);
+       }
+       return err;
+}
+
 static int parse_options(char *options, struct iso9660_options *popt)
 {
        char *p;
        int option;
+       unsigned int uv;
 
        popt->map = 'n';
        popt->rock = 1;
@@ -434,17 +447,17 @@ static int parse_options(char *options, struct 
iso9660_options *popt)
                case Opt_ignore:
                        break;
                case Opt_uid:
-                       if (match_int(&args[0], &option))
+                       if (isofs_match_uint(&args[0], &uv))
                                return 0;
-                       popt->uid = make_kuid(current_user_ns(), option);
+                       popt->uid = make_kuid(current_user_ns(), uv);
                        if (!uid_valid(popt->uid))
                                return 0;
                        popt->uid_set = 1;
                        break;
                case Opt_gid:
-                       if (match_int(&args[0], &option))
+                       if (isofs_match_uint(&args[0], &uv))
                                return 0;
-                       popt->gid = make_kgid(current_user_ns(), option);
+                       popt->gid = make_kgid(current_user_ns(), uv);
                        if (!gid_valid(popt->gid))
                                return 0;
                        popt->gid_set = 1;
-- 
2.7.4

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