btrfs: filter invalid arg for btrfs resize

Originally following cmds will work:
	# btrfs fi resize -10A  <mnt>
	# btrfs fi resize -10Gaha <mnt>
Filter the arg by checking the return pointer of memparse.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 5962236..05f8df8 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1472,6 +1472,7 @@ static noinline int btrfs_ioctl_resize(struct file *file,
        struct btrfs_trans_handle *trans;
        struct btrfs_device *device = NULL;
        char *sizestr;
+       char *retptr;
        char *devstr = NULL;
        int ret = 0;
        int mod = 0;
@@ -1539,8 +1540,8 @@ static noinline int btrfs_ioctl_resize(struct file *file,
                        mod = 1;
                        sizestr++;
                }
-               new_size = memparse(sizestr, NULL);
-               if (new_size == 0) {
+               new_size = memparse(sizestr, &retptr);
+               if (*retptr != '\0' || new_size == 0) {
                        ret = -EINVAL;
                        goto out_free;
                }