Patch "Btrfs: fix memory leak in the extent_same ioctl" has been added to the 4.1-stable tree

[<gregkh@linuxfoundation.org>]

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

    Btrfs: fix memory leak in the extent_same ioctl

to the 4.1-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-fix-memory-leak-in-the-extent_same-ioctl.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 497b4050e0eacd4c746dd396d14916b1e669849d Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana@suse.com>
Date: Fri, 3 Jul 2015 08:36:11 +0100
Subject: Btrfs: fix memory leak in the extent_same ioctl

From: Filipe Manana <fdmanana@suse.com>

commit 497b4050e0eacd4c746dd396d14916b1e669849d upstream.

We were allocating memory with memdup_user() but we were never releasing
that memory. This affected pretty much every call to the ioctl, whether
it deduplicated extents or not.

This issue was reported on IRC by Julian Taylor and on the mailing list
by Marcel Ritter, credit goes to them for finding the issue.

Reported-by: Julian Taylor <jtaylor.debian@googlemail.com>
Reported-by: Marcel Ritter <ritter.marcel@gmail.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/btrfs/ioctl.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2938,7 +2938,7 @@ out_unlock:
 static long btrfs_ioctl_file_extent_same(struct file *file,
 			struct btrfs_ioctl_same_args __user *argp)
 {
-	struct btrfs_ioctl_same_args *same;
+	struct btrfs_ioctl_same_args *same = NULL;
 	struct btrfs_ioctl_same_extent_info *info;
 	struct inode *src = file_inode(file);
 	u64 off;
@@ -2968,6 +2968,7 @@ static long btrfs_ioctl_file_extent_same
 
 	if (IS_ERR(same)) {
 		ret = PTR_ERR(same);
+		same = NULL;
 		goto out;
 	}
 
@@ -3038,6 +3039,7 @@ static long btrfs_ioctl_file_extent_same
 
 out:
 	mnt_drop_write_file(file);
+	kfree(same);
 	return ret;
 }
 


Patches currently in stable-queue which might be from fdmanana@suse.com are

queue-4.1/btrfs-fix-file-corruption-after-cloning-inline-extents.patch
queue-4.1/btrfs-fix-race-between-caching-kthread-and-returning-inode-to-inode-cache.patch
queue-4.1/btrfs-fix-list-transaction-pending_ordered-corruption.patch
queue-4.1/btrfs-fix-memory-leak-in-the-extent_same-ioctl.patch
queue-4.1/btrfs-use-kmem_cache_free-when-freeing-entry-in-inode-cache.patch
queue-4.1/btrfs-fix-fsync-data-loss-after-append-write.patch