# \[PATCH 1/2\] fbdev: sbuslib: use checked version of put\_user()

- Subsystems: FRAMEBUFFER LAYER, THE REST
- Maintainers: Helge Deller, Linus Torvalds
- List: linux-fbdev
- 2 messages, 2 authors
- Page: https://ratatoskr.run/linux-fbdev/2018/08/9144724/t

## \[PATCH 1/2\] fbdev: sbuslib: use checked version of put\_user()

- From: Dan Carpenter \<hidden\>
- Date: 2018-08-31 08:09:36 
- Message: https://ratatoskr.run/linux-fbdev/2018/08/9144724.md

```text
I'm not sure why the code assumes that only the first put_user() needs
an access_ok() check.  I have made all the put_user() and get_user()
calls checked.

Signed-off-by: Dan Carpenter <redacted>

diff --git a/drivers/video/fbdev/sbuslib.c b/drivers/video/fbdev/sbuslib.c
index a436d44f1b7f..90c51330969c 100644
--- a/drivers/video/fbdev/sbuslib.c
+++ b/drivers/video/fbdev/sbuslib.c
@@ -106,11 +106,11 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
 		struct fbtype __user *f = (struct fbtype __user *) arg;
 
 		if (put_user(type, &f->fb_type) ||
-		    __put_user(info->var.yres, &f->fb_height) ||
-		    __put_user(info->var.xres, &f->fb_width) ||
-		    __put_user(fb_depth, &f->fb_depth) ||
-		    __put_user(0, &f->fb_cmsize) ||
-		    __put_user(fb_size, &f->fb_cmsize))
+		    put_user(info->var.yres, &f->fb_height) ||
+		    put_user(info->var.xres, &f->fb_width) ||
+		    put_user(fb_depth, &f->fb_depth) ||
+		    put_user(0, &f->fb_cmsize) ||
+		    put_user(fb_size, &f->fb_cmsize))
 			return -EFAULT;
 		return 0;
 	}
@@ -125,10 +125,10 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
 		unsigned int index, count, i;
 
 		if (get_user(index, &c->index) ||
-		    __get_user(count, &c->count) ||
-		    __get_user(ured, &c->red) ||
-		    __get_user(ugreen, &c->green) ||
-		    __get_user(ublue, &c->blue))
+		    get_user(count, &c->count) ||
+		    get_user(ured, &c->red) ||
+		    get_user(ugreen, &c->green) ||
+		    get_user(ublue, &c->blue))
 			return -EFAULT;
 
 		cmap.len = 1;
@@ -165,10 +165,10 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
 		u8 red, green, blue;
 
 		if (get_user(index, &c->index) ||
-		    __get_user(count, &c->count) ||
-		    __get_user(ured, &c->red) ||
-		    __get_user(ugreen, &c->green) ||
-		    __get_user(ublue, &c->blue))
+		    get_user(count, &c->count) ||
+		    get_user(ured, &c->red) ||
+		    get_user(ugreen, &c->green) ||
+		    get_user(ublue, &c->blue))
 			return -EFAULT;
 
 		if (index + count > cmap->len)
```

## Re: \[PATCH 1/2\] fbdev: sbuslib: use checked version of put\_user()

- From: Bartlomiej Zolnierkiewicz \<hidden\>
- Date: 2018-10-08 10:42:18 
- Message: https://ratatoskr.run/linux-fbdev/2018/10/9147420.md

```text

On 08/31/2018 10:09 AM, Dan Carpenter wrote:
> I'm not sure why the code assumes that only the first put_user() needs
> an access_ok() check.  I have made all the put_user() and get_user()
> calls checked.
> 
> Signed-off-by: Dan Carpenter <redacted>

Patch queued for 4.20, thanks.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics
```