On 19 November 2012 15:30, Inki Dae <inki.dae at samsung.com> wrote: > > >> -----Original Message----- >> From: Sachin Kamat [mailto:sachin.kamat at linaro.org] >> Sent: Monday, November 19, 2012 6:56 PM >> To: Inki Dae >> Cc: dri-devel at lists.freedesktop.org; jy0922.shim at samsung.com; >> patches at linaro.org >> Subject: Re: [PATCH 1/1] drm/exynos: Fix potential NULL pointer >> dereference in exynos_drm_encoder.c >> >> Hi Inki, >> >> Thanks for your review. My comments inline. >> >> On 19 November 2012 15:14, Inki Dae <inki.dae at samsung.com> wrote: >> > >> > >> >> -----Original Message----- >> >> From: Sachin Kamat [mailto:sachin.kamat at linaro.org] >> >> Sent: Monday, November 19, 2012 6:21 PM >> >> To: dri-devel at lists.freedesktop.org >> >> Cc: inki.dae at samsung.com; jy0922.shim at samsung.com; >> > sachin.kamat at linaro.org; >> >> patches at linaro.org >> >> Subject: [PATCH 1/1] drm/exynos: Fix potential NULL pointer dereference >> in >> >> exynos_drm_encoder.c >> >> >> >> Check overlay_ops is not NULL as checked in the previous 'if' > condition. >> >> Fixes the following smatch error: >> >> drivers/gpu/drm/exynos/exynos_drm_encoder.c:509 >> >> exynos_drm_encoder_plane_disable() >> >> error: we previously assumed 'overlay_ops' could be null (see line 499) >> >> >> >> Signed-off-by: Sachin Kamat <sachin.kamat at linaro.org> >> >> --- >> >> drivers/gpu/drm/exynos/exynos_drm_encoder.c | 2 +- >> >> 1 files changed, 1 insertions(+), 1 deletions(-) >> >> >> >> diff --git a/drivers/gpu/drm/exynos/exynos_drm_encoder.c >> >> b/drivers/gpu/drm/exynos/exynos_drm_encoder.c >> >> index e51503f..a44238e 100644 >> >> --- a/drivers/gpu/drm/exynos/exynos_drm_encoder.c >> >> +++ b/drivers/gpu/drm/exynos/exynos_drm_encoder.c >> >> @@ -506,6 +506,6 @@ void exynos_drm_encoder_plane_disable(struct >> >> drm_encoder *encoder, void *data) >> >> * because the setting for disabling the overlay will be updated >> >> * at vsync. >> >> */ >> >> - if (overlay_ops->wait_for_vblank) >> >> + if (overlay_ops && overlay_ops->wait_for_vblank) >> >> overlay_ops->wait_for_vblank(manager->dev); >> > >> > This code will be removed at -next. >> >> Since this code is already in mainline, I think this patch should be >> applied as a fix during this rc (for completeness). >> You may subsequently delete it in the next release as per your plan. >> > > And NULL pointer checking was already done above like below, > if (overlay_ops && overlay_ops->disable) > overlay_ops->disable(manager->dev, zpos); Correct. But that check is applicable only for that one statement (overlay_ops->disable(manager->dev, zpos);).
Similar check needs to be added to below 'if' code too. > > This is your missing point. > >> > >> > Thanks, >> > Inki Dae >> > >> >> } >> >> -- >> >> 1.7.4.1 >> > >> >> >> >> -- >> With warm regards, >> Sachin > -- With warm regards, Sachin
