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Date:   Thu, 2 Jul 2020 10:25:58 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Sasha Levin <sashal@kernel.org>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Waiman Long <longman@redhat.com>,
        David Sterba <dsterba@suse.com>, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH AUTOSEL 5.7 11/53] btrfs: use kfree() in
 btrfs_ioctl_get_subvol_info()
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References: <20200702012202.2700645-1-sashal@kernel.org>
 <20200702012202.2700645-11-sashal@kernel.org>
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On Wed, Jul 01, 2020 at 09:21:20PM -0400, Sasha Levin wrote:
> From: Waiman Long <longman@redhat.com>
> 
> [ Upstream commit b091f7fede97cc64f7aaad3eeb37965aebee3082 ]
> 
> In btrfs_ioctl_get_subvol_info(), there is a classic case where kzalloc()
> was incorrectly paired with kzfree(). According to David Sterba, there
> isn't any sensitive information in the subvol_info that needs to be
> cleared before freeing. So kzfree() isn't really needed, use kfree()
> instead.

I don't think this patch is necessary for any stable tree, it's meant
only to ease merging a tree-wide patchset to rename kzfree.  In btrfs
code there was no point using it so it's plain kfree.