| From 8e8833ac289896cd10a30f35cc36ee11051aeaea Mon Sep 17 00:00:00 2001 |
| From: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> |
| Date: Fri, 22 Mar 2019 15:26:57 +0000 |
| Subject: drm/meson: Uninstall IRQ handler |
| |
| [ Upstream commit 2d8f92897ad816f5dda54b2ed2fd9f2d7cb1abde ] |
| |
| meson_drv_unbind() doesn't unregister the IRQ handler, which can lead to |
| use-after-free if the IRQ fires after unbind: |
| |
| [ 64.656876] Unable to handle kernel paging request at virtual address ffff000011706dbc |
| ... |
| [ 64.662001] pc : meson_irq+0x18/0x30 [meson_drm] |
| |
| I'm assuming that a similar problem could happen on the error path of |
| bind(), so uninstall the IRQ handler there as well. |
| |
| Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller") |
| Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> |
| Acked-by: Neil Armstrong <narmstrong@baylibre.com> |
| Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> |
| Link: https://patchwork.freedesktop.org/patch/msgid/20190322152657.13752-2-jean-philippe.brucker@arm.com |
| Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org> |
| --- |
| drivers/gpu/drm/meson/meson_drv.c | 5 ++++- |
| 1 file changed, 4 insertions(+), 1 deletion(-) |
| |
| diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c |
| index 1a1b0b9cf1fa..0608243c3387 100644 |
| --- a/drivers/gpu/drm/meson/meson_drv.c |
| +++ b/drivers/gpu/drm/meson/meson_drv.c |
| @@ -277,10 +277,12 @@ static int meson_drv_bind_master(struct device *dev, bool has_components) |
| |
| ret = drm_dev_register(drm, 0); |
| if (ret) |
| - goto free_drm; |
| + goto uninstall_irq; |
| |
| return 0; |
| |
| +uninstall_irq: |
| + drm_irq_uninstall(drm); |
| free_drm: |
| drm_dev_unref(drm); |
| |
| @@ -298,6 +300,7 @@ static void meson_drv_unbind(struct device *dev) |
| struct drm_device *drm = priv->drm; |
| |
| drm_dev_unregister(drm); |
| + drm_irq_uninstall(drm); |
| drm_kms_helper_poll_fini(drm); |
| drm_fbdev_cma_fini(priv->fbdev); |
| drm_mode_config_cleanup(drm); |
| -- |
| 2.19.1 |
| |