Patch "btrfs: check unsupported filters in balance arguments" has been added to the 4.2-stable tree

This is a note to let you know that I've just added the patch titled

btrfs: check unsupported filters in balance arguments

to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
btrfs-check-unsupported-filters-in-balance-arguments.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: David Sterba <[email protected]>
Date: Mon, 12 Oct 2015 16:55:54 +0200
Subject: btrfs: check unsupported filters in balance arguments

From: David Sterba <[email protected]>

commit 849ef9286f30c88113906dc35f44a499c0cb385d 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.

---
 fs/btrfs/ioctl.c   |    5 +++++
 fs/btrfs/volumes.h |    8 ++++++++
 2 files changed, 13 insertions(+)

@@ -4652,6 +4652,11 @@ locked:
 		goto out_bctl;
 	}
 
+	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

@@ -384,6 +384,14 @@ struct map_lookup {
 	 BTRFS_BALANCE_ARGS_VRANGE |		\
 	 BTRFS_BALANCE_ARGS_LIMIT)
 
+#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

Patches currently in stable-queue which might be from [email protected] are

queue-4.2/btrfs-check-unsupported-filters-in-balance-arguments.patch queue-4.2/btrfs-fix-signed-overflows-in-btrfs_sync_file.patch