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Date:   Wed, 24 Oct 2018 20:44:43 +0200
From:   David Sterba <dsterba@suse.cz>
To:     robbieko <robbieko@synology.com>
Cc:     linux-btrfs@vger.kernel.org
Subject: Re: [PATCH] btrfs-progs: super-recover: fix double free fs_devices
 memory
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On Fri, Oct 12, 2018 at 04:25:23PM +0800, robbieko wrote:
> From: Robbie Ko <robbieko@synology.com>
> 
> super-recover collects btrfs devices information using existed
> functions scan_one_devices().
> 
> Problem is fs_devices is freed twice. One in __open_ctree_fd() when
> error happens and the other in btrfs_close_devices(recover.fs_devices)
> when root is NULL.
> 
> Commit "30fd6f2e92695c355c8f76b8887cd4fade60cdac" add force-close
> all opened device before program exit, to avoid memory leak in all
> btrfs sub-command.
> Therefore, there is an unnecessary freed of fs_devices in
> btrfs_recover_superblocks.
> 
> Fix this problem by remove unnecessary freed of fs_devices.
> 
> Signed-off-by: Robbie Ko <robbieko@synology.com>

The fix for the double free has been in the devel branch, but thanks
anyway.