* [PATCH v3 0/4] Fix mediatek-drm coverity issues
@ 2023-06-21 10:22 Jason-JH.Lin
2023-06-21 10:22 ` [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory Jason-JH.Lin
` (3 more replies)
0 siblings, 4 replies; 18+ messages in thread
From: Jason-JH.Lin @ 2023-06-21 10:22 UTC (permalink / raw)
To: Chun-Kuang Hu, AngeloGioacchino Del Regno, Alexandre Mergnat
Cc: Jason-JH . Lin, Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
Add this patch series to fix some mediatek-drm coverity issues.
Change in v3:
1. swap Fixes and Signed tag.
2. change cast (__u64) to '=' then ' *='.
Change in v2:
1. remove kfree(pkt) in mtk_drm_crtc_create_pkt().
2. change the statement of cnt reach to MAX_CRTC.
3. drop the mtk_gem_obj initialized patch.
4. change casting from unsined long to __u64.
5. add 'int offset' for multiplier calculation.
6. drop the unrelavaent modification in dereference null check patch.
Jason-JH.Lin (4):
drm/mediatek: Remove freeing not dynamic allocated memory
drm/mediatek: Add cnt checking for coverity issue
drm/mediatek: Add casting before assign
drm/mediatek: Fix dereference before null check
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 7 ++----
drivers/gpu/drm/mediatek/mtk_drm_drv.c | 5 ++++-
drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 ++-
drivers/gpu/drm/mediatek/mtk_drm_plane.c | 28 ++++++++++++------------
4 files changed, 22 insertions(+), 21 deletions(-)
--
2.18.0
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory
2023-06-21 10:22 [PATCH v3 0/4] Fix mediatek-drm coverity issues Jason-JH.Lin
@ 2023-06-21 10:22 ` Jason-JH.Lin
2023-06-21 12:12 ` Alexandre Mergnat
2023-07-10 4:01 ` CK Hu (胡俊光)
2023-06-21 10:22 ` [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue Jason-JH.Lin
` (2 subsequent siblings)
3 siblings, 2 replies; 18+ messages in thread
From: Jason-JH.Lin @ 2023-06-21 10:22 UTC (permalink / raw)
To: Chun-Kuang Hu, AngeloGioacchino Del Regno, Alexandre Mergnat
Cc: Jason-JH . Lin, Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
Fixing the coverity issue of:
mtk_drm_cmdq_pkt_destroy frees address of mtk_crtc->cmdq_handle
So remove the free function.
Fixes: 7627122fd1c0 ("drm/mediatek: Add cmdq_handle in mtk_crtc")
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index d40142842f85..8d44f3df116f 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -116,10 +116,9 @@ static int mtk_drm_cmdq_pkt_create(struct cmdq_client *client, struct cmdq_pkt *
dma_addr_t dma_addr;
pkt->va_base = kzalloc(size, GFP_KERNEL);
- if (!pkt->va_base) {
- kfree(pkt);
+ if (!pkt->va_base)
return -ENOMEM;
- }
+
pkt->buf_size = size;
pkt->cl = (void *)client;
@@ -129,7 +128,6 @@ static int mtk_drm_cmdq_pkt_create(struct cmdq_client *client, struct cmdq_pkt *
if (dma_mapping_error(dev, dma_addr)) {
dev_err(dev, "dma map failed, size=%u\n", (u32)(u64)size);
kfree(pkt->va_base);
- kfree(pkt);
return -ENOMEM;
}
@@ -145,7 +143,6 @@ static void mtk_drm_cmdq_pkt_destroy(struct cmdq_pkt *pkt)
dma_unmap_single(client->chan->mbox->dev, pkt->pa_base, pkt->buf_size,
DMA_TO_DEVICE);
kfree(pkt->va_base);
- kfree(pkt);
}
#endif
--
2.18.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue
2023-06-21 10:22 [PATCH v3 0/4] Fix mediatek-drm coverity issues Jason-JH.Lin
2023-06-21 10:22 ` [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory Jason-JH.Lin
@ 2023-06-21 10:22 ` Jason-JH.Lin
2023-06-21 12:15 ` Alexandre Mergnat
2023-07-10 6:45 ` CK Hu (胡俊光)
2023-06-21 10:22 ` [PATCH v3 3/4] drm/mediatek: Add casting before assign Jason-JH.Lin
2023-06-21 10:22 ` [PATCH v3 4/4] drm/mediatek: Fix dereference before null check Jason-JH.Lin
3 siblings, 2 replies; 18+ messages in thread
From: Jason-JH.Lin @ 2023-06-21 10:22 UTC (permalink / raw)
To: Chun-Kuang Hu, AngeloGioacchino Del Regno, Alexandre Mergnat
Cc: Jason-JH . Lin, Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
CERT-C Characters and Strings (CERT STR31-C)
all_drm_priv[cnt] evaluates to an address that could be at negative
offset of an array.
In mtk_drm_get_all_drm_priv():
Guarantee that storage for strings has sufficient space for character
data and the null terminator.
So change cnt to unsigned int and check its max value.
Fixes: 1ef7ed48356c ("drm/mediatek: Modify mediatek-drm for mt8195 multi mmsys support")
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
drivers/gpu/drm/mediatek/mtk_drm_drv.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index 6dcb4ba2466c..fc217e0acd45 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -354,7 +354,7 @@ static bool mtk_drm_get_all_drm_priv(struct device *dev)
const struct of_device_id *of_id;
struct device_node *node;
struct device *drm_dev;
- int cnt = 0;
+ unsigned int cnt = 0;
int i, j;
for_each_child_of_node(phandle->parent, node) {
@@ -375,6 +375,9 @@ static bool mtk_drm_get_all_drm_priv(struct device *dev)
all_drm_priv[cnt] = dev_get_drvdata(drm_dev);
if (all_drm_priv[cnt] && all_drm_priv[cnt]->mtk_drm_bound)
cnt++;
+
+ if (cnt == MAX_CRTC)
+ break;
}
if (drm_priv->data->mmsys_dev_num == cnt) {
--
2.18.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-06-21 10:22 [PATCH v3 0/4] Fix mediatek-drm coverity issues Jason-JH.Lin
2023-06-21 10:22 ` [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory Jason-JH.Lin
2023-06-21 10:22 ` [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue Jason-JH.Lin
@ 2023-06-21 10:22 ` Jason-JH.Lin
2023-06-21 12:34 ` Alexandre Mergnat
2023-07-14 5:45 ` CK Hu (胡俊光)
2023-06-21 10:22 ` [PATCH v3 4/4] drm/mediatek: Fix dereference before null check Jason-JH.Lin
3 siblings, 2 replies; 18+ messages in thread
From: Jason-JH.Lin @ 2023-06-21 10:22 UTC (permalink / raw)
To: Chun-Kuang Hu, AngeloGioacchino Del Regno, Alexandre Mergnat
Cc: Jason-JH . Lin, Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
1. Add casting before assign to avoid the unintentional integer
overflow or unintended sign extension.
2. Add a int varriable for multiplier calculation instead of calculating
different types multiplier with dma_addr_t varriable directly.
Fixes: 1a64a7aff8da ("drm/mediatek: Fix cursor plane no update")
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
---
drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 ++-
drivers/gpu/drm/mediatek/mtk_drm_plane.c | 22 +++++++++++++---------
2 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
index a25b28d3ee90..da087d74612d 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -121,7 +121,8 @@ int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
int ret;
args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
- args->size = args->pitch * args->height;
+ args->size = args->pitch;
+ args->size *= args->height;
mtk_gem = mtk_drm_gem_create(dev, args->size, false);
if (IS_ERR(mtk_gem))
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
index 31f9420aff6f..1cd41454d545 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
@@ -145,6 +145,7 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
dma_addr_t addr;
dma_addr_t hdr_addr = 0;
unsigned int hdr_pitch = 0;
+ int offset;
gem = fb->obj[0];
mtk_gem = to_mtk_gem_obj(gem);
@@ -154,8 +155,10 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
modifier = fb->modifier;
if (modifier == DRM_FORMAT_MOD_LINEAR) {
- addr += (new_state->src.x1 >> 16) * fb->format->cpp[0];
- addr += (new_state->src.y1 >> 16) * pitch;
+ offset = (new_state->src.x1 >> 16) * fb->format->cpp[0];
+ addr += offset;
+ offset = (new_state->src.y1 >> 16) * pitch;
+ addr += offset;
} else {
int width_in_blocks = ALIGN(fb->width, AFBC_DATA_BLOCK_WIDTH)
/ AFBC_DATA_BLOCK_WIDTH;
@@ -163,21 +166,22 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
/ AFBC_DATA_BLOCK_HEIGHT;
int x_offset_in_blocks = (new_state->src.x1 >> 16) / AFBC_DATA_BLOCK_WIDTH;
int y_offset_in_blocks = (new_state->src.y1 >> 16) / AFBC_DATA_BLOCK_HEIGHT;
- int hdr_size;
+ int hdr_size, hdr_offset;
hdr_pitch = width_in_blocks * AFBC_HEADER_BLOCK_SIZE;
pitch = width_in_blocks * AFBC_DATA_BLOCK_WIDTH *
AFBC_DATA_BLOCK_HEIGHT * fb->format->cpp[0];
hdr_size = ALIGN(hdr_pitch * height_in_blocks, AFBC_HEADER_ALIGNMENT);
+ hdr_offset = hdr_pitch * y_offset_in_blocks +
+ AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks;
+ hdr_addr = addr + hdr_offset;
- hdr_addr = addr + hdr_pitch * y_offset_in_blocks +
- AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks;
/* The data plane is offset by 1 additional block. */
- addr = addr + hdr_size +
- pitch * y_offset_in_blocks +
- AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT *
- fb->format->cpp[0] * (x_offset_in_blocks + 1);
+ offset = pitch * y_offset_in_blocks +
+ AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT *
+ fb->format->cpp[0] * (x_offset_in_blocks + 1);
+ addr = addr + hdr_size + offset;
}
mtk_plane_state->pending.enable = true;
--
2.18.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH v3 4/4] drm/mediatek: Fix dereference before null check
2023-06-21 10:22 [PATCH v3 0/4] Fix mediatek-drm coverity issues Jason-JH.Lin
` (2 preceding siblings ...)
2023-06-21 10:22 ` [PATCH v3 3/4] drm/mediatek: Add casting before assign Jason-JH.Lin
@ 2023-06-21 10:22 ` Jason-JH.Lin
2023-06-21 12:38 ` Alexandre Mergnat
2023-07-14 5:52 ` CK Hu (胡俊光)
3 siblings, 2 replies; 18+ messages in thread
From: Jason-JH.Lin @ 2023-06-21 10:22 UTC (permalink / raw)
To: Chun-Kuang Hu, AngeloGioacchino Del Regno, Alexandre Mergnat
Cc: Jason-JH . Lin, Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
Null-checking state suggests that it may be null, but it has already
been dereferenced on drm_atomic_get_new_plane_state(state, plane).
The parameter state will never be NULL currently, so just remove the
state is NULL flow in this function.
Fixes: 5ddb0bd4ddc3 ("drm/atomic: Pass the full state to planes async atomic check and update")
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
drivers/gpu/drm/mediatek/mtk_drm_plane.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
index 1cd41454d545..4828ffa75467 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
@@ -122,11 +122,7 @@ static int mtk_plane_atomic_async_check(struct drm_plane *plane,
if (ret)
return ret;
- if (state)
- crtc_state = drm_atomic_get_existing_crtc_state(state,
- new_plane_state->crtc);
- else /* Special case for asynchronous cursor updates. */
- crtc_state = new_plane_state->crtc->state;
+ crtc_state = drm_atomic_get_existing_crtc_state(state, new_plane_state->crtc);
return drm_atomic_helper_check_plane_state(plane->state, crtc_state,
DRM_PLANE_NO_SCALING,
--
2.18.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory
2023-06-21 10:22 ` [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory Jason-JH.Lin
@ 2023-06-21 12:12 ` Alexandre Mergnat
2023-07-10 4:01 ` CK Hu (胡俊光)
1 sibling, 0 replies; 18+ messages in thread
From: Alexandre Mergnat @ 2023-06-21 12:12 UTC (permalink / raw)
To: Jason-JH.Lin, Chun-Kuang Hu, AngeloGioacchino Del Regno
Cc: Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
On 21/06/2023 12:22, Jason-JH.Lin wrote:
> Fixing the coverity issue of:
> mtk_drm_cmdq_pkt_destroy frees address of mtk_crtc->cmdq_handle
>
> So remove the free function.
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
--
Regards,
Alexandre
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue
2023-06-21 10:22 ` [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue Jason-JH.Lin
@ 2023-06-21 12:15 ` Alexandre Mergnat
2023-07-10 6:45 ` CK Hu (胡俊光)
1 sibling, 0 replies; 18+ messages in thread
From: Alexandre Mergnat @ 2023-06-21 12:15 UTC (permalink / raw)
To: Jason-JH.Lin, Chun-Kuang Hu, AngeloGioacchino Del Regno
Cc: Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
On 21/06/2023 12:22, Jason-JH.Lin wrote:
> CERT-C Characters and Strings (CERT STR31-C)
> all_drm_priv[cnt] evaluates to an address that could be at negative
> offset of an array.
>
> In mtk_drm_get_all_drm_priv():
> Guarantee that storage for strings has sufficient space for character
> data and the null terminator.
>
> So change cnt to unsigned int and check its max value.
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
--
Regards,
Alexandre
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-06-21 10:22 ` [PATCH v3 3/4] drm/mediatek: Add casting before assign Jason-JH.Lin
@ 2023-06-21 12:34 ` Alexandre Mergnat
2023-06-22 8:02 ` Jason-JH Lin (林睿祥)
2023-07-14 5:45 ` CK Hu (胡俊光)
1 sibling, 1 reply; 18+ messages in thread
From: Alexandre Mergnat @ 2023-06-21 12:34 UTC (permalink / raw)
To: Jason-JH.Lin, Chun-Kuang Hu, AngeloGioacchino Del Regno
Cc: Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
On 21/06/2023 12:22, Jason-JH.Lin wrote:
> 1. Add casting before assign to avoid the unintentional integer
> overflow or unintended sign extension.
> 2. Add a int varriable for multiplier calculation instead of calculating
> different types multiplier with dma_addr_t varriable directly.
>
> Fixes: 1a64a7aff8da ("drm/mediatek: Fix cursor plane no update")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 ++-
> drivers/gpu/drm/mediatek/mtk_drm_plane.c | 22 +++++++++++++---------
> 2 files changed, 15 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> index a25b28d3ee90..da087d74612d 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> @@ -121,7 +121,8 @@ int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
> int ret;
>
> args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
> - args->size = args->pitch * args->height;
> + args->size = args->pitch;
> + args->size *= args->height;
>
> mtk_gem = mtk_drm_gem_create(dev, args->size, false);
> if (IS_ERR(mtk_gem))
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> index 31f9420aff6f..1cd41454d545 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> @@ -145,6 +145,7 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
> dma_addr_t addr;
> dma_addr_t hdr_addr = 0;
> unsigned int hdr_pitch = 0;
> + int offset;
I agree with Angelo, please set offset as unsigned.
>
> gem = fb->obj[0];
> mtk_gem = to_mtk_gem_obj(gem);
> @@ -154,8 +155,10 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
> modifier = fb->modifier;
>
> if (modifier == DRM_FORMAT_MOD_LINEAR) {
> - addr += (new_state->src.x1 >> 16) * fb->format->cpp[0];
> - addr += (new_state->src.y1 >> 16) * pitch;
> + offset = (new_state->src.x1 >> 16) * fb->format->cpp[0];
> + addr += offset;
> + offset = (new_state->src.y1 >> 16) * pitch;
> + addr += offset;
> } else {
> int width_in_blocks = ALIGN(fb->width, AFBC_DATA_BLOCK_WIDTH)
> / AFBC_DATA_BLOCK_WIDTH;
> @@ -163,21 +166,22 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
> / AFBC_DATA_BLOCK_HEIGHT;
> int x_offset_in_blocks = (new_state->src.x1 >> 16) / AFBC_DATA_BLOCK_WIDTH;
> int y_offset_in_blocks = (new_state->src.y1 >> 16) / AFBC_DATA_BLOCK_HEIGHT;
> - int hdr_size;
> + int hdr_size, hdr_offset;
>
> hdr_pitch = width_in_blocks * AFBC_HEADER_BLOCK_SIZE;
> pitch = width_in_blocks * AFBC_DATA_BLOCK_WIDTH *
> AFBC_DATA_BLOCK_HEIGHT * fb->format->cpp[0];
>
> hdr_size = ALIGN(hdr_pitch * height_in_blocks, AFBC_HEADER_ALIGNMENT);
> + hdr_offset = hdr_pitch * y_offset_in_blocks +
> + AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks;
> + hdr_addr = addr + hdr_offset;
>
> - hdr_addr = addr + hdr_pitch * y_offset_in_blocks +
> - AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks;
> /* The data plane is offset by 1 additional block. */
> - addr = addr + hdr_size +
> - pitch * y_offset_in_blocks +
> - AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT *
> - fb->format->cpp[0] * (x_offset_in_blocks + 1);
> + offset = pitch * y_offset_in_blocks +
> + AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT *
> + fb->format->cpp[0] * (x_offset_in_blocks + 1);
> + addr = addr + hdr_size + offset;
> }
>
> mtk_plane_state->pending.enable = true;
--
Regards,
Alexandre
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 4/4] drm/mediatek: Fix dereference before null check
2023-06-21 10:22 ` [PATCH v3 4/4] drm/mediatek: Fix dereference before null check Jason-JH.Lin
@ 2023-06-21 12:38 ` Alexandre Mergnat
2023-07-14 5:52 ` CK Hu (胡俊光)
1 sibling, 0 replies; 18+ messages in thread
From: Alexandre Mergnat @ 2023-06-21 12:38 UTC (permalink / raw)
To: Jason-JH.Lin, Chun-Kuang Hu, AngeloGioacchino Del Regno
Cc: Singo Chang, linux-kernel, dri-devel,
Project_Global_Chrome_Upstream_Group, Jason-ch Chen, Nancy Lin,
Johnson Wang, Shawn Sung, Matthias Brugger, linux-mediatek,
linux-arm-kernel
On 21/06/2023 12:22, Jason-JH.Lin wrote:
> Null-checking state suggests that it may be null, but it has already
> been dereferenced on drm_atomic_get_new_plane_state(state, plane).
>
> The parameter state will never be NULL currently, so just remove the
> state is NULL flow in this function.
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
--
Regards,
Alexandre
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-06-21 12:34 ` Alexandre Mergnat
@ 2023-06-22 8:02 ` Jason-JH Lin (林睿祥)
2023-07-12 13:07 ` Alexandre Mergnat
0 siblings, 1 reply; 18+ messages in thread
From: Jason-JH Lin (林睿祥) @ 2023-06-22 8:02 UTC (permalink / raw)
To: amergnat, chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
Johnson Wang (王聖鑫),
Shawn Sung (宋孝謙),
matthias.bgg, linux-mediatek, linux-arm-kernel
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Hi Alexandre,
Thanks for the reviews.
On Wed, 2023-06-21 at 14:34 +0200, Alexandre Mergnat wrote:
>
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>
>
> On 21/06/2023 12:22, Jason-JH.Lin wrote:
> > 1. Add casting before assign to avoid the unintentional integer
> > overflow or unintended sign extension.
> > 2. Add a int varriable for multiplier calculation instead of
> calculating
> > different types multiplier with dma_addr_t varriable directly.
> >
> > Fixes: 1a64a7aff8da ("drm/mediatek: Fix cursor plane no update")
> > Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 ++-
> > drivers/gpu/drm/mediatek/mtk_drm_plane.c | 22 +++++++++++++----
> -----
> > 2 files changed, 15 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > index a25b28d3ee90..da087d74612d 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > @@ -121,7 +121,8 @@ int mtk_drm_gem_dumb_create(struct drm_file
> *file_priv, struct drm_device *dev,
> > int ret;
> >
> > args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
> > -args->size = args->pitch * args->height;
> > +args->size = args->pitch;
> > +args->size *= args->height;
> >
> > mtk_gem = mtk_drm_gem_create(dev, args->size, false);
> > if (IS_ERR(mtk_gem))
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> > index 31f9420aff6f..1cd41454d545 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> > @@ -145,6 +145,7 @@ static void mtk_plane_update_new_state(struct
> drm_plane_state *new_state,
> > dma_addr_t addr;
> > dma_addr_t hdr_addr = 0;
> > unsigned int hdr_pitch = 0;
> > +int offset;
>
> I agree with Angelo, please set offset as unsigned.
>
I think offset should be unsigned, but since src.x1 and src.y1 are
'int'. That means 'unsigned int' offset will be very big when src.x1 or
src.y1 is negative.
So I just use 'int' for offset here.
Regards,
Jason-JH.Lin
> >
> > gem = fb->obj[0];
> > mtk_gem = to_mtk_gem_obj(gem);
> > @@ -154,8 +155,10 @@ static void mtk_plane_update_new_state(struct
> drm_plane_state *new_state,
> > modifier = fb->modifier;
> >
> > if (modifier == DRM_FORMAT_MOD_LINEAR) {
> > -addr += (new_state->src.x1 >> 16) * fb->format->cpp[0];
> > -addr += (new_state->src.y1 >> 16) * pitch;
> > +offset = (new_state->src.x1 >> 16) * fb->format->cpp[0];
> > +addr += offset;
> > +offset = (new_state->src.y1 >> 16) * pitch;
> > +addr += offset;
>
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory
2023-06-21 10:22 ` [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory Jason-JH.Lin
2023-06-21 12:12 ` Alexandre Mergnat
@ 2023-07-10 4:01 ` CK Hu (胡俊光)
1 sibling, 0 replies; 18+ messages in thread
From: CK Hu (胡俊光) @ 2023-07-10 4:01 UTC (permalink / raw)
To: amergnat, Jason-JH Lin (林睿祥),
chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
linux-mediatek, Shawn Sung (宋孝謙),
matthias.bgg, Johnson Wang (王聖鑫),
linux-arm-kernel
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Hi, Jason:
On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> Fixing the coverity issue of:
> mtk_drm_cmdq_pkt_destroy frees address of mtk_crtc->cmdq_handle
>
> So remove the free function.
Reviewed-by: CK Hu <ck.hu@mediatek.com>
>
> Fixes: 7627122fd1c0 ("drm/mediatek: Add cmdq_handle in mtk_crtc")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index d40142842f85..8d44f3df116f 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -116,10 +116,9 @@ static int mtk_drm_cmdq_pkt_create(struct
> cmdq_client *client, struct cmdq_pkt *
> dma_addr_t dma_addr;
>
> pkt->va_base = kzalloc(size, GFP_KERNEL);
> - if (!pkt->va_base) {
> - kfree(pkt);
> + if (!pkt->va_base)
> return -ENOMEM;
> - }
> +
> pkt->buf_size = size;
> pkt->cl = (void *)client;
>
> @@ -129,7 +128,6 @@ static int mtk_drm_cmdq_pkt_create(struct
> cmdq_client *client, struct cmdq_pkt *
> if (dma_mapping_error(dev, dma_addr)) {
> dev_err(dev, "dma map failed, size=%u\n",
> (u32)(u64)size);
> kfree(pkt->va_base);
> - kfree(pkt);
> return -ENOMEM;
> }
>
> @@ -145,7 +143,6 @@ static void mtk_drm_cmdq_pkt_destroy(struct
> cmdq_pkt *pkt)
> dma_unmap_single(client->chan->mbox->dev, pkt->pa_base, pkt-
> >buf_size,
> DMA_TO_DEVICE);
> kfree(pkt->va_base);
> - kfree(pkt);
> }
> #endif
>
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue
2023-06-21 10:22 ` [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue Jason-JH.Lin
2023-06-21 12:15 ` Alexandre Mergnat
@ 2023-07-10 6:45 ` CK Hu (胡俊光)
1 sibling, 0 replies; 18+ messages in thread
From: CK Hu (胡俊光) @ 2023-07-10 6:45 UTC (permalink / raw)
To: amergnat, Jason-JH Lin (林睿祥),
chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
linux-mediatek, Shawn Sung (宋孝謙),
matthias.bgg, Johnson Wang (王聖鑫),
linux-arm-kernel
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Hi, Jason:
On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> CERT-C Characters and Strings (CERT STR31-C)
> all_drm_priv[cnt] evaluates to an address that could be at negative
> offset of an array.
>
> In mtk_drm_get_all_drm_priv():
> Guarantee that storage for strings has sufficient space for character
> data and the null terminator.
>
> So change cnt to unsigned int and check its max value.
Reviewed-by: CK Hu <ck.hu@mediatek.com>
>
> Fixes: 1ef7ed48356c ("drm/mediatek: Modify mediatek-drm for mt8195
> multi mmsys support")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_drv.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> index 6dcb4ba2466c..fc217e0acd45 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> @@ -354,7 +354,7 @@ static bool mtk_drm_get_all_drm_priv(struct
> device *dev)
> const struct of_device_id *of_id;
> struct device_node *node;
> struct device *drm_dev;
> - int cnt = 0;
> + unsigned int cnt = 0;
> int i, j;
>
> for_each_child_of_node(phandle->parent, node) {
> @@ -375,6 +375,9 @@ static bool mtk_drm_get_all_drm_priv(struct
> device *dev)
> all_drm_priv[cnt] = dev_get_drvdata(drm_dev);
> if (all_drm_priv[cnt] && all_drm_priv[cnt]-
> >mtk_drm_bound)
> cnt++;
> +
> + if (cnt == MAX_CRTC)
> + break;
> }
>
> if (drm_priv->data->mmsys_dev_num == cnt) {
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-06-22 8:02 ` Jason-JH Lin (林睿祥)
@ 2023-07-12 13:07 ` Alexandre Mergnat
0 siblings, 0 replies; 18+ messages in thread
From: Alexandre Mergnat @ 2023-07-12 13:07 UTC (permalink / raw)
To: Jason-JH Lin (林睿祥),
chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
Johnson Wang (王聖鑫),
Shawn Sung (宋孝謙),
matthias.bgg, linux-mediatek, linux-arm-kernel
On 22/06/2023 10:02, Jason-JH Lin (林睿祥) wrote:
>> drm_plane_state *new_state,
>> > dma_addr_t addr;
>> > dma_addr_t hdr_addr = 0;
>> > unsigned int hdr_pitch = 0;
>> > +int offset;
>>
>> I agree with Angelo, please set offset as unsigned.
>>
> I think offset should be unsigned, but since src.x1 and src.y1 are
> 'int'. That means 'unsigned int' offset will be very big when src.x1 or
> src.y1 is negative.
> So I just use 'int' for offset here.
Ok
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
--
Regards,
Alexandre
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-06-21 10:22 ` [PATCH v3 3/4] drm/mediatek: Add casting before assign Jason-JH.Lin
2023-06-21 12:34 ` Alexandre Mergnat
@ 2023-07-14 5:45 ` CK Hu (胡俊光)
2023-07-14 6:45 ` Jason-JH Lin (林睿祥)
1 sibling, 1 reply; 18+ messages in thread
From: CK Hu (胡俊光) @ 2023-07-14 5:45 UTC (permalink / raw)
To: amergnat, Jason-JH Lin (林睿祥),
chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
linux-mediatek, Shawn Sung (宋孝謙),
matthias.bgg, Johnson Wang (王聖鑫),
linux-arm-kernel
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Hi, Jason:
On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> 1. Add casting before assign to avoid the unintentional integer
> overflow or unintended sign extension.
> 2. Add a int varriable for multiplier calculation instead of
> calculating
> different types multiplier with dma_addr_t varriable directly.
I agree with these modification, but the title does not match the
modification.
Regards,
CK
>
> Fixes: 1a64a7aff8da ("drm/mediatek: Fix cursor plane no update")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 ++-
> drivers/gpu/drm/mediatek/mtk_drm_plane.c | 22 +++++++++++++---------
> 2 files changed, 15 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> index a25b28d3ee90..da087d74612d 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> @@ -121,7 +121,8 @@ int mtk_drm_gem_dumb_create(struct drm_file
> *file_priv, struct drm_device *dev,
> int ret;
>
> args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
> - args->size = args->pitch * args->height;
> + args->size = args->pitch;
> + args->size *= args->height;
>
> mtk_gem = mtk_drm_gem_create(dev, args->size, false);
> if (IS_ERR(mtk_gem))
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> index 31f9420aff6f..1cd41454d545 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> @@ -145,6 +145,7 @@ static void mtk_plane_update_new_state(struct
> drm_plane_state *new_state,
> dma_addr_t addr;
> dma_addr_t hdr_addr = 0;
> unsigned int hdr_pitch = 0;
> + int offset;
>
> gem = fb->obj[0];
> mtk_gem = to_mtk_gem_obj(gem);
> @@ -154,8 +155,10 @@ static void mtk_plane_update_new_state(struct
> drm_plane_state *new_state,
> modifier = fb->modifier;
>
> if (modifier == DRM_FORMAT_MOD_LINEAR) {
> - addr += (new_state->src.x1 >> 16) * fb->format->cpp[0];
> - addr += (new_state->src.y1 >> 16) * pitch;
> + offset = (new_state->src.x1 >> 16) * fb->format-
> >cpp[0];
> + addr += offset;
> + offset = (new_state->src.y1 >> 16) * pitch;
> + addr += offset;
> } else {
> int width_in_blocks = ALIGN(fb->width,
> AFBC_DATA_BLOCK_WIDTH)
> / AFBC_DATA_BLOCK_WIDTH;
> @@ -163,21 +166,22 @@ static void mtk_plane_update_new_state(struct
> drm_plane_state *new_state,
> / AFBC_DATA_BLOCK_HEIGHT;
> int x_offset_in_blocks = (new_state->src.x1 >> 16) /
> AFBC_DATA_BLOCK_WIDTH;
> int y_offset_in_blocks = (new_state->src.y1 >> 16) /
> AFBC_DATA_BLOCK_HEIGHT;
> - int hdr_size;
> + int hdr_size, hdr_offset;
>
> hdr_pitch = width_in_blocks * AFBC_HEADER_BLOCK_SIZE;
> pitch = width_in_blocks * AFBC_DATA_BLOCK_WIDTH *
> AFBC_DATA_BLOCK_HEIGHT * fb->format->cpp[0];
>
> hdr_size = ALIGN(hdr_pitch * height_in_blocks,
> AFBC_HEADER_ALIGNMENT);
> + hdr_offset = hdr_pitch * y_offset_in_blocks +
> + AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks;
> + hdr_addr = addr + hdr_offset;
>
> - hdr_addr = addr + hdr_pitch * y_offset_in_blocks +
> - AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks;
> /* The data plane is offset by 1 additional block. */
> - addr = addr + hdr_size +
> - pitch * y_offset_in_blocks +
> - AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT *
> - fb->format->cpp[0] * (x_offset_in_blocks + 1);
> + offset = pitch * y_offset_in_blocks +
> + AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT
> *
> + fb->format->cpp[0] * (x_offset_in_blocks + 1);
> + addr = addr + hdr_size + offset;
> }
>
> mtk_plane_state->pending.enable = true;
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 4/4] drm/mediatek: Fix dereference before null check
2023-06-21 10:22 ` [PATCH v3 4/4] drm/mediatek: Fix dereference before null check Jason-JH.Lin
2023-06-21 12:38 ` Alexandre Mergnat
@ 2023-07-14 5:52 ` CK Hu (胡俊光)
1 sibling, 0 replies; 18+ messages in thread
From: CK Hu (胡俊光) @ 2023-07-14 5:52 UTC (permalink / raw)
To: amergnat, Jason-JH Lin (林睿祥),
chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
Johnson Wang (王聖鑫),
Shawn Sung (宋孝謙),
matthias.bgg, linux-mediatek, linux-arm-kernel
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Hi, Jason:
On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> Null-checking state suggests that it may be null, but it has already
> been dereferenced on drm_atomic_get_new_plane_state(state, plane).
>
> The parameter state will never be NULL currently, so just remove the
> state is NULL flow in this function.
Reviewed-by: CK Hu <ck.hu@mediatek.com>
>
> Fixes: 5ddb0bd4ddc3 ("drm/atomic: Pass the full state to planes async
> atomic check and update")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_plane.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> index 1cd41454d545..4828ffa75467 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> @@ -122,11 +122,7 @@ static int mtk_plane_atomic_async_check(struct
> drm_plane *plane,
> if (ret)
> return ret;
>
> - if (state)
> - crtc_state = drm_atomic_get_existing_crtc_state(state,
> - new_pla
> ne_state->crtc);
> - else /* Special case for asynchronous cursor updates. */
> - crtc_state = new_plane_state->crtc->state;
> + crtc_state = drm_atomic_get_existing_crtc_state(state,
> new_plane_state->crtc);
>
> return drm_atomic_helper_check_plane_state(plane->state,
> crtc_state,
> DRM_PLANE_NO_SCALING
> ,
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-07-14 5:45 ` CK Hu (胡俊光)
@ 2023-07-14 6:45 ` Jason-JH Lin (林睿祥)
2023-07-17 13:17 ` David Laight
0 siblings, 1 reply; 18+ messages in thread
From: Jason-JH Lin (林睿祥) @ 2023-07-14 6:45 UTC (permalink / raw)
To: CK Hu (胡俊光),
amergnat, chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
Johnson Wang (王聖鑫),
Shawn Sung (宋孝謙),
matthias.bgg, linux-mediatek, linux-arm-kernel
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[-- Attachment #2: Type: text/plain, Size: 1013 bytes --]
Hi CK,
Thanks for the reviews.
On Fri, 2023-07-14 at 05:45 +0000, CK Hu (胡俊光) wrote:
> Hi, Jason:
>
> On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> > 1. Add casting before assign to avoid the unintentional integer
> > overflow or unintended sign extension.
> > 2. Add a int varriable for multiplier calculation instead of
> > calculating
> > different types multiplier with dma_addr_t varriable directly.
>
> I agree with these modification, but the title does not match the
> modification.
>
> Regards,
> CK
I'll change the title and commit msg at the next version below:
Fix unintentional integer overflow in multiplying different types
1. Instead of multiplying 2 variable of different types. Change to
assign a value of one variable and then multiply the other variable.
2. Add a int variable for multiplier calculation instead of calculating
different types multiplier with dma_addr_t variable directly.
Thanks!
Regards,
Jason-JH.Lin
>
^ permalink raw reply [flat|nested] 18+ messages in thread
* RE: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-07-14 6:45 ` Jason-JH Lin (林睿祥)
@ 2023-07-17 13:17 ` David Laight
2023-07-18 15:30 ` Jason-JH Lin (林睿祥)
0 siblings, 1 reply; 18+ messages in thread
From: David Laight @ 2023-07-17 13:17 UTC (permalink / raw)
To: 'Jason-JH Lin (林睿祥)',
CK Hu (胡俊光),
amergnat, chunkuang.hu, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
Johnson Wang (王聖鑫),
Shawn Sung (宋孝謙),
matthias.bgg, linux-mediatek, linux-arm-kernel
From: Jason-JH Lin
> Sent: 14 July 2023 07:46
>
> Hi CK,
>
> Thanks for the reviews.
>
> On Fri, 2023-07-14 at 05:45 +0000, CK Hu (胡俊光) wrote:
> > Hi, Jason:
> >
> > On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> > > 1. Add casting before assign to avoid the unintentional integer
> > > overflow or unintended sign extension.
> > > 2. Add a int varriable for multiplier calculation instead of
> > > calculating
> > > different types multiplier with dma_addr_t varriable directly.
> >
> > I agree with these modification, but the title does not match the
> > modification.
> >
> > Regards,
> > CK
>
> I'll change the title and commit msg at the next version below:
>
> Fix unintentional integer overflow in multiplying different types
>
> 1. Instead of multiplying 2 variable of different types. Change to
> assign a value of one variable and then multiply the other variable.
>
> 2. Add a int variable for multiplier calculation instead of calculating
> different types multiplier with dma_addr_t variable directly.
I'm pretty sure the patch makes absolutely no difference.
In C all arithmetic is done with char/short (inc. unsigned)
promoted to int.
So the only likely overflow is if the values exceed 2^31.
Since the temporaries you are using are 'int' this isn't true.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 3/4] drm/mediatek: Add casting before assign
2023-07-17 13:17 ` David Laight
@ 2023-07-18 15:30 ` Jason-JH Lin (林睿祥)
0 siblings, 0 replies; 18+ messages in thread
From: Jason-JH Lin (林睿祥) @ 2023-07-18 15:30 UTC (permalink / raw)
To: CK Hu (胡俊光),
amergnat, chunkuang.hu, David.Laight, angelogioacchino.delregno
Cc: Singo Chang (張興國),
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Jason-ch Chen (陳建豪),
Nancy Lin (林欣螢),
Johnson Wang (王聖鑫),
Shawn Sung (宋孝謙),
matthias.bgg, linux-mediatek, linux-arm-kernel
[-- Attachment #1: Type: text/html, Size: 6680 bytes --]
[-- Attachment #2: Type: text/plain, Size: 3041 bytes --]
Hi David,
Thanks for the reviews.
On Mon, 2023-07-17 at 13:17 +0000, David Laight wrote:
>
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
> From: Jason-JH Lin
> > Sent: 14 July 2023 07:46
> >
> > Hi CK,
> >
> > Thanks for the reviews.
> >
> > On Fri, 2023-07-14 at 05:45 +0000, CK Hu (胡俊光) wrote:
> > > Hi, Jason:
> > >
> > > On Wed, 2023-06-21 at 18:22 +0800, Jason-JH.Lin wrote:
> > > > 1. Add casting before assign to avoid the unintentional integer
> > > > overflow or unintended sign extension.
> > > > 2. Add a int varriable for multiplier calculation instead of
> > > > calculating
> > > > different types multiplier with dma_addr_t varriable
> directly.
> > >
> > > I agree with these modification, but the title does not match the
> > > modification.
> > >
> > > Regards,
> > > CK
> >
> > I'll change the title and commit msg at the next version below:
> >
> > Fix unintentional integer overflow in multiplying different types
> >
> > 1. Instead of multiplying 2 variable of different types. Change to
> > assign a value of one variable and then multiply the other
> variable.
> >
> > 2. Add a int variable for multiplier calculation instead of
> calculating
> > different types multiplier with dma_addr_t variable directly.
>
> I'm pretty sure the patch makes absolutely no difference.
> In C all arithmetic is done with char/short (inc. unsigned)
> promoted to int.
`char/short promoted to int` could you give me an example or more
detail for this?
I can't really understand about that. Thanks~
>
> So the only likely overflow is if the values exceed 2^31.
> Since the temporaries you are using are 'int' this isn't true.
>
According to the modification:
+ int offset;
...
- addr += (new_state->src.x1 >> 16) * fb->format->cpp[0];
- addr += (new_state->src.y1 >> 16) * pitch;
+ offset = (new_state->src.x1 >> 16) * fb->format->cpp[0];
+ addr += offset;
+ offset = (new_state->src.y1 >> 16) * pitch;
+ addr += offset;
The main reasons why I use `int offset` here is that
src.x1 and src.y1 are `32bits int` defined in
struct drm_rect {
int x1, y1, x2, y2;
};
We know that the values of `x1 * cpp` and `y1 * pitch` would never
cause 32bits overflow actually.
So I just add the same type `int offset` as a 32bits variable to avoid
Coverity checker catching the unintentional overflow of
`64bits addr += 32bits x1 * 8bits cpp` and
`64bits addr += 32bits y1 * 32bits pitch`.
Another reason is that using `unsined int offset` to store the
calculation result of negative x1 and y1, offset may be a very big
number because of overflow of `negative int`.
Do you agree with that?
Regards,
Jason-JH.Lin
> David
>
> -
> Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes,
> MK1 1PT, UK
> Registration No: 1397386 (Wales)
>
^ permalink raw reply [flat|nested] 18+ messages in thread
end of thread, other threads:[~2023-07-18 15:31 UTC | newest]
Thread overview: 18+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-06-21 10:22 [PATCH v3 0/4] Fix mediatek-drm coverity issues Jason-JH.Lin
2023-06-21 10:22 ` [PATCH v3 1/4] drm/mediatek: Remove freeing not dynamic allocated memory Jason-JH.Lin
2023-06-21 12:12 ` Alexandre Mergnat
2023-07-10 4:01 ` CK Hu (胡俊光)
2023-06-21 10:22 ` [PATCH v3 2/4] drm/mediatek: Add cnt checking for coverity issue Jason-JH.Lin
2023-06-21 12:15 ` Alexandre Mergnat
2023-07-10 6:45 ` CK Hu (胡俊光)
2023-06-21 10:22 ` [PATCH v3 3/4] drm/mediatek: Add casting before assign Jason-JH.Lin
2023-06-21 12:34 ` Alexandre Mergnat
2023-06-22 8:02 ` Jason-JH Lin (林睿祥)
2023-07-12 13:07 ` Alexandre Mergnat
2023-07-14 5:45 ` CK Hu (胡俊光)
2023-07-14 6:45 ` Jason-JH Lin (林睿祥)
2023-07-17 13:17 ` David Laight
2023-07-18 15:30 ` Jason-JH Lin (林睿祥)
2023-06-21 10:22 ` [PATCH v3 4/4] drm/mediatek: Fix dereference before null check Jason-JH.Lin
2023-06-21 12:38 ` Alexandre Mergnat
2023-07-14 5:52 ` CK Hu (胡俊光)
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