[PATCH v2 0/2] Fix sloppy typing in the FB area copying routines

[PATCH v2 0/2] Fix sloppy typing in the FB area copying routines

[Sergey Shtylyov]

Here are 2 patches against the 'master' branch of Linus' 'linux.git' repo...

In {cfb|sys}_copyarea(), the local variable bits_per_line is needlessly typed
as *unsigned long* -- which is a 32-bit type on the 32-bit arches and a 64-bit
type on the 64-bit arches;; that variable's value is derived from the __u32
typed fb_fix_screeninfo::line_length field (multiplied by 8u) and a 32-bit
*unsigned int* type should still be enough to store the # of bits per line.

Sergey Shtylyov (2):
  video: fbdev: core: cfbcopyarea: fix sloppy typing
  video: fbdev: core: syscopyarea: fix sloppy typing

 drivers/video/fbdev/core/cfbcopyarea.c | 2 +-
 drivers/video/fbdev/core/syscopyarea.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

-- 
2.26.3

[PATCH v2 1/2] video: fbdev: core: cfbcopyarea: fix sloppy typing

[Sergey Shtylyov]

In cfb_copyarea(), the local variable bits_per_line is needlessly typed as
*unsigned long* -- which is a 32-bit type on the 32-bit arches and a 64-bit
type on the 64-bit arches; that variable's value is derived from the __u32
typed fb_fix_screeninfo::line_length field (multiplied by 8u) and a 32-bit
*unsigned int* type should still be enough to store the # of bits per line.

Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
---
 drivers/video/fbdev/core/cfbcopyarea.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/core/cfbcopyarea.c b/drivers/video/fbdev/core/cfbcopyarea.c
index 6d4bfeecee35..5b80bf3dae50 100644
--- a/drivers/video/fbdev/core/cfbcopyarea.c
+++ b/drivers/video/fbdev/core/cfbcopyarea.c
@@ -382,7 +382,7 @@ void cfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
 {
 	u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
 	u32 height = area->height, width = area->width;
-	unsigned long const bits_per_line = p->fix.line_length*8u;
+	unsigned int const bits_per_line = p->fix.line_length * 8u;
 	unsigned long __iomem *base = NULL;
 	int bits = BITS_PER_LONG, bytes = bits >> 3;
 	unsigned dst_idx = 0, src_idx = 0, rev_copy = 0;
-- 
2.26.3

[PATCH v2 2/2] video: fbdev: core: syscopyarea: fix sloppy typing

[Sergey Shtylyov]

In sys_copyarea(), the local variable bits_per_line is needlessly typed as
*unsigned long* -- which is a 32-bit type on the 32-bit arches and a 64-bit
type on the 64-bit arches; that variable's value is derived from the __u32
typed fb_fix_screeninfo::line_length field (multiplied by 8u) and a 32-bit
*unsigned int* type should still be enough to store the # of bits per line.

Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
---
 drivers/video/fbdev/core/syscopyarea.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/core/syscopyarea.c b/drivers/video/fbdev/core/syscopyarea.c
index c1eda3190968..7b8bd3a2bedc 100644
--- a/drivers/video/fbdev/core/syscopyarea.c
+++ b/drivers/video/fbdev/core/syscopyarea.c
@@ -316,7 +316,7 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area)
 {
 	u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
 	u32 height = area->height, width = area->width;
-	unsigned long const bits_per_line = p->fix.line_length*8u;
+	unsigned int const bits_per_line = p->fix.line_length * 8u;
 	unsigned long *base = NULL;
 	int bits = BITS_PER_LONG, bytes = bits >> 3;
 	unsigned dst_idx = 0, src_idx = 0, rev_copy = 0;
-- 
2.26.3

Re: [PATCH v2 1/2] video: fbdev: core: cfbcopyarea: fix sloppy typing

[Helge Deller]

On 10/13/23 22:50, Sergey Shtylyov wrote:
> In cfb_copyarea(), the local variable bits_per_line is needlessly typed as
> *unsigned long* -- which is a 32-bit type on the 32-bit arches and a 64-bit
> type on the 64-bit arches; that variable's value is derived from the __u32
> typed fb_fix_screeninfo::line_length field (multiplied by 8u) and a 32-bit
> *unsigned int* type should still be enough to store the # of bits per line.
>
> Found by Linux Verification Center (linuxtesting.org) with the Svace static
> analysis tool.
>
> Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>

applied both patches.

Thanks!
Helge

> ---
>   drivers/video/fbdev/core/cfbcopyarea.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/video/fbdev/core/cfbcopyarea.c b/drivers/video/fbdev/core/cfbcopyarea.c
> index 6d4bfeecee35..5b80bf3dae50 100644
> --- a/drivers/video/fbdev/core/cfbcopyarea.c
> +++ b/drivers/video/fbdev/core/cfbcopyarea.c
> @@ -382,7 +382,7 @@ void cfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
>   {
>   	u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
>   	u32 height = area->height, width = area->width;
> -	unsigned long const bits_per_line = p->fix.line_length*8u;
> +	unsigned int const bits_per_line = p->fix.line_length * 8u;
>   	unsigned long __iomem *base = NULL;
>   	int bits = BITS_PER_LONG, bytes = bits >> 3;
>   	unsigned dst_idx = 0, src_idx = 0, rev_copy = 0;