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    SubjectRe: [PATCH v2] drm/amdgpu: fix multiple memory leaks
    Hi Christian,

    On Thu, Sep 19, 2019 at 4:05 AM Koenig, Christian
    <Christian.Koenig@amd.com> wrote:
    >
    > > +out4:
    > > + kfree(i2s_pdata);
    > > +out3:
    > > + kfree(adev->acp.acp_res);
    > > +out2:
    > > + kfree(adev->acp.acp_cell);
    > > +out1:
    > > + kfree(adev->acp.acp_genpd);
    >
    > kfree on a NULL pointer is harmless, so a single error label should be
    > sufficient.

    That is true, but I notice that the adev structure comes from outside this
    driver:

    static int acp_hw_init(void *handle)
    {
    ...
    struct amdgpu_device *adev = (struct amdgpu_device *)handle;
    ...
    }

    As far as I can tell, the init() does not explicitly set these to NULL:
    adev->acp.acp_res
    adev->acp.acp_cell
    adev->acp.acp_genpd

    I am assuming that core code sets these to NULL, before calling
    acp_hw_init(). But is that guaranteed or simply a happy accident?
    Ie. if they are NULL today, are they likely to remain NULL tomorrow?

    Because calling kfree() on a stale pointer would be, well
    not good. Especially not on an error path, which typically
    does not receive much testing, if any.

    My apologies if I have misinterpreted this, I am not familiar with
    this code base.

    Sven

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