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	Tue, 04 Jun 2024 19:10:05 +0000
Date: Tue, 4 Jun 2024 20:10:04 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Felix Kuehling <felix.kuehling@amd.com>
Cc: amd-gfx@lists.freedesktop.org,
	Maling list - DRI developers <dri-devel@lists.freedesktop.org>,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 1/2][RFC] amdgpu: fix a race in kfd_mem_export_dmabuf()
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References: <20240604021255.GO1629371@ZenIV>
 <20240604021354.GA3053943@ZenIV>
 <611b4f6e-e91b-4759-a170-fb43819000ce@amd.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Tue, Jun 04, 2024 at 02:08:30PM -0400, Felix Kuehling wrote:
> > +int drm_gem_prime_handle_to_fd(struct drm_device *dev,
> > +			       struct drm_file *file_priv, uint32_t handle,
> > +			       uint32_t flags,
> > +			       int *prime_fd)
> > +{
> > +	struct dma_buf *dmabuf;
> > +	int fd = get_unused_fd_flags(flags);
> > +
> > +	if (fd < 0)
> > +		return fd;
> > +
> > +	dmabuf = drm_gem_prime_handle_to_dmabuf(dev, file_priv, handle, flags);
> > +	if (IS_ERR(dmabuf))
> > +		return PTR_ERR(dmabuf);

That ought to be
	if (IS_ERR(dmabuf)) {
		put_unused_fd(fd);
		return PTR_ERR(dmabuf);
	}
or we'll leak an allocated descriptor.  Will fix and repost...