btrfs: check unsupported filters in balance arguments

commit 8eb934591f8bf584969454a658f629cd06e59f3a upstream.

We don't verify that all the balance filter arguments supplemented by
the flags are actually known to the kernel. Thus we let it silently pass
and do nothing.

At the moment this means only the 'limit' filter, but we're going to add
a few more soon so it's better to have that fixed. Also in older stable
kernels so that it works with newer userspace tools.

Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index b9d2ce0d409333e231f5b8a692c748e7bed46a4e..8b71c6755e047174df1e24a8e29cded52e072c04 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4528,6 +4528,11 @@ locked:
                bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
        }
 
+       if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
+               ret = -EINVAL;
+               goto out_bargs;
+       }
+
 do_balance:
        /*
         * Ownership of bctl and mutually_exclusive_operation_running

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 2aaa00c4781637f508302829ed51e3ae05402c84..4292c68196ffb1d6fbdb7dfd649d2578fde41179 100644 (file)
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -260,6 +260,14 @@ struct map_lookup {
 #define BTRFS_BALANCE_ARGS_VRANGE      (1ULL << 4)
 #define BTRFS_BALANCE_ARGS_LIMIT       (1ULL << 5)
 
+#define BTRFS_BALANCE_ARGS_MASK                        \
+       (BTRFS_BALANCE_ARGS_PROFILES |          \
+        BTRFS_BALANCE_ARGS_USAGE |             \
+        BTRFS_BALANCE_ARGS_DEVID |             \
+        BTRFS_BALANCE_ARGS_DRANGE |            \
+        BTRFS_BALANCE_ARGS_VRANGE |            \
+        BTRFS_BALANCE_ARGS_LIMIT)
+
 /*
  * Profile changing flags.  When SOFT is set we won't relocate chunk if
  * it already has the target profile (even though it may be