* Re: [PATCH] drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy()
2024-09-12 8:44 [PATCH] drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy() Dan Carpenter
@ 2024-09-12 9:05 ` AngeloGioacchino Del Regno
2024-10-23 5:47 ` CK Hu (胡俊光)
2024-10-23 14:13 ` Chun-Kuang Hu
2 siblings, 0 replies; 4+ messages in thread
From: AngeloGioacchino Del Regno @ 2024-09-12 9:05 UTC (permalink / raw)
To: Dan Carpenter, Chun-Kuang Hu
Cc: Philipp Zabel, David Airlie, Simona Vetter, Matthias Brugger,
dri-devel, linux-mediatek, linux-kernel, linux-arm-kernel,
kernel-janitors, Jason-JH Lin (林睿祥)
Il 12/09/24 10:44, Dan Carpenter ha scritto:
> In mtk_crtc_create(), if the call to mbox_request_channel() fails then we
> set the "mtk_crtc->cmdq_client.chan" pointer to NULL. In that situation,
> we do not call cmdq_pkt_create().
>
> During the cleanup, we need to check if the "mtk_crtc->cmdq_client.chan"
> is NULL first before calling cmdq_pkt_destroy(). Calling
> cmdq_pkt_destroy() is unnecessary if we didn't call cmdq_pkt_create() and
> it will result in a NULL pointer dereference.
>
> Fixes: 7627122fd1c0 ("drm/mediatek: Add cmdq_handle in mtk_crtc")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy()
2024-09-12 8:44 [PATCH] drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy() Dan Carpenter
2024-09-12 9:05 ` AngeloGioacchino Del Regno
@ 2024-10-23 5:47 ` CK Hu (胡俊光)
2024-10-23 14:13 ` Chun-Kuang Hu
2 siblings, 0 replies; 4+ messages in thread
From: CK Hu (胡俊光) @ 2024-10-23 5:47 UTC (permalink / raw)
To: dan.carpenter@linaro.org, chunkuang.hu@kernel.org
Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mediatek@lists.infradead.org,
Jason-JH Lin (林睿祥), simona@ffwll.ch,
p.zabel@pengutronix.de, dri-devel@lists.freedesktop.org,
airlied@gmail.com, linux-arm-kernel@lists.infradead.org,
matthias.bgg@gmail.com, AngeloGioacchino Del Regno
Hi, Dan:
On Thu, 2024-09-12 at 11:44 +0300, Dan Carpenter wrote:
>
> External email : Please do not click links or open attachments until you have verified the sender or the content.
> In mtk_crtc_create(), if the call to mbox_request_channel() fails then we
> set the "mtk_crtc->cmdq_client.chan" pointer to NULL. In that situation,
> we do not call cmdq_pkt_create().
>
> During the cleanup, we need to check if the "mtk_crtc->cmdq_client.chan"
> is NULL first before calling cmdq_pkt_destroy(). Calling
> cmdq_pkt_destroy() is unnecessary if we didn't call cmdq_pkt_create() and
> it will result in a NULL pointer dereference.
Reviewed-by: CK Hu <ck.hu@mediatek.com>
>
> Fixes: 7627122fd1c0 ("drm/mediatek: Add cmdq_handle in mtk_crtc")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> drivers/gpu/drm/mediatek/mtk_crtc.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
> index 175b00e5a253..c15013792583 100644
> --- a/drivers/gpu/drm/mediatek/mtk_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
> @@ -127,9 +127,8 @@ static void mtk_crtc_destroy(struct drm_crtc *crtc)
>
> mtk_mutex_put(mtk_crtc->mutex);
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> -cmdq_pkt_destroy(&mtk_crtc->cmdq_client, &mtk_crtc->cmdq_handle);
> -
> if (mtk_crtc->cmdq_client.chan) {
> +cmdq_pkt_destroy(&mtk_crtc->cmdq_client, &mtk_crtc->cmdq_handle);
> mbox_free_channel(mtk_crtc->cmdq_client.chan);
> mtk_crtc->cmdq_client.chan = NULL;
> }
> --
> 2.45.2
>
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy()
2024-09-12 8:44 [PATCH] drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy() Dan Carpenter
2024-09-12 9:05 ` AngeloGioacchino Del Regno
2024-10-23 5:47 ` CK Hu (胡俊光)
@ 2024-10-23 14:13 ` Chun-Kuang Hu
2 siblings, 0 replies; 4+ messages in thread
From: Chun-Kuang Hu @ 2024-10-23 14:13 UTC (permalink / raw)
To: Dan Carpenter
Cc: Chun-Kuang Hu, Philipp Zabel, David Airlie, Simona Vetter,
Matthias Brugger, AngeloGioacchino Del Regno, dri-devel,
linux-mediatek, linux-kernel, linux-arm-kernel, kernel-janitors,
Jason-JH Lin (林睿祥)
Hi, Dan:
Dan Carpenter <dan.carpenter@linaro.org> 於 2024年9月12日 週四 下午4:45寫道：
>
> In mtk_crtc_create(), if the call to mbox_request_channel() fails then we
> set the "mtk_crtc->cmdq_client.chan" pointer to NULL. In that situation,
> we do not call cmdq_pkt_create().
>
> During the cleanup, we need to check if the "mtk_crtc->cmdq_client.chan"
> is NULL first before calling cmdq_pkt_destroy(). Calling
> cmdq_pkt_destroy() is unnecessary if we didn't call cmdq_pkt_create() and
> it will result in a NULL pointer dereference.
Applied to mediatek-drm-fixes [1], thanks.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-fixes
Regards,
Chun-Kuang.
>
> Fixes: 7627122fd1c0 ("drm/mediatek: Add cmdq_handle in mtk_crtc")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> drivers/gpu/drm/mediatek/mtk_crtc.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
> index 175b00e5a253..c15013792583 100644
> --- a/drivers/gpu/drm/mediatek/mtk_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
> @@ -127,9 +127,8 @@ static void mtk_crtc_destroy(struct drm_crtc *crtc)
>
> mtk_mutex_put(mtk_crtc->mutex);
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> - cmdq_pkt_destroy(&mtk_crtc->cmdq_client, &mtk_crtc->cmdq_handle);
> -
> if (mtk_crtc->cmdq_client.chan) {
> + cmdq_pkt_destroy(&mtk_crtc->cmdq_client, &mtk_crtc->cmdq_handle);
> mbox_free_channel(mtk_crtc->cmdq_client.chan);
> mtk_crtc->cmdq_client.chan = NULL;
> }
> --
> 2.45.2
>
^ permalink raw reply [flat|nested] 4+ messages in thread