btrfs: check unsupported filters in balance arguments

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.

Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 4df0f2bd9af7964c6e5d03ac700721cddaffb103..7375cf2e6bbf9952603138350ef43538e63a04cb 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4691,6 +4691,11 @@ 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 99c208f6718d03353364d198ffa292f8bfa25a06..b8e64ea984f18e3b8d38630358c1e8122a229cb8 100644 (file)
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -381,6 +381,14 @@ 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