[PATCH 3.15 012/109] fuse: handle large user and group ID

Greg Kroah-Hartman
2014-07-26T19:42:39Z

From: Miklos Szeredi <mszeredi@suse.cz>

commit 233a01fa9c4c7c41238537e8db8434667ff28a2f upstream.

If the number in "user_id=N" or "group_id=N" mount options was larger than
INT_MAX then fuse returned EINVAL.

Fix this to handle all valid uid/gid values.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/fuse/inode.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)

--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -478,6 +478,17 @@ static const match_table_t tokens = {
{OPT_ERR, NULL}
};

+static int fuse_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_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
{
char *p;
@@ -488,6 +499,7 @@ static int parse_fuse_opt(char *opt, str
while ((p = strsep(&opt, ",")) != NULL) {
int token;
int value;
+ unsigned uv;
substring_t args[MAX_OPT_ARGS];
if (!*p)
continue;
@@ -511,18 +523,18 @@ static int parse_fuse_opt(char *opt, str
break;

case OPT_USER_ID:
- if (match_int(&args[0], &value))
+ if (fuse_match_uint(&args[0], &uv))
return 0;
- d->user_id = make_kuid(current_user_ns(), value);
+ d->user_id = make_kuid(current_user_ns(), uv);
if (!uid_valid(d->user_id))
return 0;
d->user_id_present = 1;
break;

case OPT_GROUP_ID:
- if (match_int(&args[0], &value))
+ if (fuse_match_uint(&args[0], &uv))
return 0;
- d->group_id = make_kgid(current_user_ns(), value);
+ d->group_id = make_kgid(current_user_ns(), uv);
if (!gid_valid(d->group_id))
return 0;
d->group_id_present = 1;