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Date: Wed, 20 Jan 2016 16:15:52 -0800
From: Nikhilesh Reddy <reddyn@codeaurora.org>
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To: Jann Horn <jann@thejh.net>
CC: torvalds@linux-foundation.org, Miklos Szeredi <miklos@szeredi.hu>,
	fuse-devel <fuse-devel@lists.sourceforge.net>,
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	Antonio SJ Musumeci <trapexit@spawn.link>, sven.utcke@gmx.de,
	Nikolaus Rath <nikolaus@rath.org>,
	Jann Horn <jannhorn@googlemail.com>
Subject: Re: [PATCH v3] fuse: Add support for passthrough read/write
References: <56A01642.7030806@codeaurora.org> <20160120233841.GA16235@pc.thejh.net>
In-Reply-To: <20160120233841.GA16235@pc.thejh.net>
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On Wed 20 Jan 2016 03:38:41 PM PST, Jann Horn wrote:
> On Wed, Jan 20, 2016 at 03:20:34PM -0800, Nikhilesh Reddy wrote:
>> Add support for filesystem passthrough read/write of files
>> when enabled in userspace through the option FUSE_PASSTHROUGH.
> [...]
>> +	daemon_fd = (int)open_out->passthrough_fd;
>> +	if (daemon_fd < 0)
>> +		return;
>> +
>> +	passthrough_filp = fget_raw(daemon_fd);
>> +	if (!passthrough_filp)
>> +		return;
>> +
>> +	passthrough_inode = file_inode(passthrough_filp);
>> +	passthrough_sb = passthrough_inode->i_sb;
>> +	fs_stack_depth = passthrough_sb->s_stack_depth + 1;
>> +
>> +	/* If we reached the stacking limit go through regular io */
>> +	if (fs_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
>> +		pr_err("FUSE: maximum fs stacking depth exceeded, cannot use passthrough for this file\n");
>> +		return;
>> +	}
>
> I think this needs an fput() in the error case to prevent a refcount leak.

Whoops my bad .. forgot to commit! :(
Thanks for the catch
fixed ... sending patch v4 in a few minutes
-- 
Thanks
Nikhilesh Reddy

Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.