[PATCH] video/via: Convert to kstrtou8_from_user

Subsystems: framebuffer layer, the rest

STALE5249d

4 messages, 3 authors, 2012-05-10 · open the first message on its own page

[PATCH] video/via: Convert to kstrtou8_from_user

From: Peter Huewe <peterhuewe@gmx.de>
Date: 2012-04-14 23:25:14

This patch replaces the code for getting an number from a
userspace buffer by a simple call to kstrou8_from_user.
This makes it easier to read and less error prone.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
---
 drivers/video/via/viafbdev.c |   26 ++++++++++----------------
 1 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/video/via/viafbdev.c b/drivers/video/via/viafbdev.c
index 0c88375..5b0d524 100644
--- a/drivers/video/via/viafbdev.c
+++ b/drivers/video/via/viafbdev.c

@@ -1276,17 +1276,14 @@ static int viafb_dfph_proc_open(struct inode *inode, struct file *file)
 static ssize_t viafb_dfph_proc_write(struct file *file,
 	const char __user *buffer, size_t count, loff_t *pos)
 {
-	char buf[20];
+	int err;
 	u8 reg_val = 0;
-	unsigned long length;
 	if (count < 1)
 		return -EINVAL;
-	length = count > 20 ? 20 : count;
-	if (copy_from_user(&buf[0], buffer, length))
-		return -EFAULT;
-	buf[length - 1] = '\0';	/*Ensure end string */
-	if (kstrtou8(buf, 0, &reg_val) < 0)
-		return -EINVAL;
+	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+	if (err)
+		return err;
+
 	viafb_write_reg_mask(CR97, VIACR, reg_val, 0x0f);
 	return count;
 }

@@ -1316,17 +1313,14 @@ static int viafb_dfpl_proc_open(struct inode *inode, struct file *file)
 static ssize_t viafb_dfpl_proc_write(struct file *file,
 	const char __user *buffer, size_t count, loff_t *pos)
 {
-	char buf[20];
+	int err;
 	u8 reg_val = 0;
-	unsigned long length;
 	if (count < 1)
 		return -EINVAL;
-	length = count > 20 ? 20 : count;
-	if (copy_from_user(&buf[0], buffer, length))
-		return -EFAULT;
-	buf[length - 1] = '\0';	/*Ensure end string */
-	if (kstrtou8(buf, 0, &reg_val) < 0)
-		return -EINVAL;
+	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+	if (err)
+		return err;
+
 	viafb_write_reg_mask(CR99, VIACR, reg_val, 0x0f);
 	return count;
 }

-- 
1.7.3.4

Re: [PATCH] video/via: Convert to kstrtou8_from_user

From: Alexey Dobriyan <hidden>
Date: 2012-04-16 16:36:30

On Sun, Apr 15, 2012 at 2:24 AM, Peter Huewe [off-list ref] wrote:

This patch replaces the code for getting an number from a
userspace buffer by a simple call to kstrou8_from_user.
This makes it easier to read and less error prone.

Initialization with 0 is not necessary then.
Also "count < 1" check could be dropped, since empty string will fail
with EINVAL.
Otherwise OK.

quoted hunk

--- a/drivers/video/via/viafbdev.c
+++ b/drivers/video/via/viafbdev.c

@@ -1276,17 +1276,14 @@ static int viafb_dfph_proc_open(struct inode *inode, struct file *file)

 static ssize_t viafb_dfph_proc_write(struct file *file,
       const char __user *buffer, size_t count, loff_t *pos)
 {
-       char buf[20];
+       int err;
       u8 reg_val = 0;
-       unsigned long length;
       if (count < 1)
               return -EINVAL;
-       length = count > 20 ? 20 : count;
-       if (copy_from_user(&buf[0], buffer, length))
-               return -EFAULT;
-       buf[length - 1] = '\0'; /*Ensure end string */
-       if (kstrtou8(buf, 0, &reg_val) < 0)
-               return -EINVAL;
+       err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+       if (err)
+               return err;
+
       viafb_write_reg_mask(CR97, VIACR, reg_val, 0x0f);
       return count;
 }

@@ -1316,17 +1313,14 @@ static int viafb_dfpl_proc_open(struct inode *inode, struct file *file)

 static ssize_t viafb_dfpl_proc_write(struct file *file,
       const char __user *buffer, size_t count, loff_t *pos)
 {
-       char buf[20];
+       int err;
       u8 reg_val = 0;
-       unsigned long length;
       if (count < 1)
               return -EINVAL;
-       length = count > 20 ? 20 : count;
-       if (copy_from_user(&buf[0], buffer, length))
-               return -EFAULT;
-       buf[length - 1] = '\0'; /*Ensure end string */
-       if (kstrtou8(buf, 0, &reg_val) < 0)
-               return -EINVAL;
+       err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+       if (err)
+               return err;
+
       viafb_write_reg_mask(CR99, VIACR, reg_val, 0x0f);
       return count;
 }
--
1.7.3.4

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[PATCH v2] video/via: Convert to kstrtou8_from_user

From: Peter Huewe <peterhuewe@gmx.de>
Date: 2012-05-04 00:23:27

This patch replaces the code for getting an number from a
userspace buffer by a simple call to kstrou8_from_user.
This makes it easier to read and less error prone.

v2:
removed initialization of reg_val and dropped check if count < 1

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
---
@Alexey: Thanks for the review/feedback!
 drivers/video/via/viafbdev.c |   34 ++++++++++++----------------------
 1 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/drivers/video/via/viafbdev.c b/drivers/video/via/viafbdev.c
index a13c258..88bf5ba 100644
--- a/drivers/video/via/viafbdev.c
+++ b/drivers/video/via/viafbdev.c

@@ -1279,17 +1279,12 @@ static int viafb_dfph_proc_open(struct inode *inode, struct file *file)
 static ssize_t viafb_dfph_proc_write(struct file *file,
 	const char __user *buffer, size_t count, loff_t *pos)
 {
-	char buf[20];
-	u8 reg_val = 0;
-	unsigned long length;
-	if (count < 1)
-		return -EINVAL;
-	length = count > 20 ? 20 : count;
-	if (copy_from_user(&buf[0], buffer, length))
-		return -EFAULT;
-	buf[length - 1] = '\0';	/*Ensure end string */
-	if (kstrtou8(buf, 0, &reg_val) < 0)
-		return -EINVAL;
+	int err;
+	u8 reg_val;
+	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+	if (err)
+		return err;
+
 	viafb_write_reg_mask(CR97, VIACR, reg_val, 0x0f);
 	return count;
 }

@@ -1319,17 +1314,12 @@ static int viafb_dfpl_proc_open(struct inode *inode, struct file *file)
 static ssize_t viafb_dfpl_proc_write(struct file *file,
 	const char __user *buffer, size_t count, loff_t *pos)
 {
-	char buf[20];
-	u8 reg_val = 0;
-	unsigned long length;
-	if (count < 1)
-		return -EINVAL;
-	length = count > 20 ? 20 : count;
-	if (copy_from_user(&buf[0], buffer, length))
-		return -EFAULT;
-	buf[length - 1] = '\0';	/*Ensure end string */
-	if (kstrtou8(buf, 0, &reg_val) < 0)
-		return -EINVAL;
+	int err;
+	u8 reg_val;
+	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+	if (err)
+		return err;
+
 	viafb_write_reg_mask(CR99, VIACR, reg_val, 0x0f);
 	return count;
 }

-- 
1.7.3.4

Re: [PATCH v2] video/via: Convert to kstrtou8_from_user

From: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Date: 2012-05-10 00:19:45

On 05/04/2012 12:23 AM, Peter Huewe wrote:

This patch replaces the code for getting an number from a
userspace buffer by a simple call to kstrou8_from_user.
This makes it easier to read and less error prone.

v2:
removed initialization of reg_val and dropped check if count < 1

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

Applied.


Thanks,

Florian Tobias Schandinat

quoted hunk

---
@Alexey: Thanks for the review/feedback!
 drivers/video/via/viafbdev.c |   34 ++++++++++++----------------------
 1 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/drivers/video/via/viafbdev.c b/drivers/video/via/viafbdev.c
index a13c258..88bf5ba 100644
--- a/drivers/video/via/viafbdev.c
+++ b/drivers/video/via/viafbdev.c

@@ -1279,17 +1279,12 @@ static int viafb_dfph_proc_open(struct inode *inode, struct file *file)
 static ssize_t viafb_dfph_proc_write(struct file *file,
 	const char __user *buffer, size_t count, loff_t *pos)
 {
-	char buf[20];
-	u8 reg_val = 0;
-	unsigned long length;
-	if (count < 1)
-		return -EINVAL;
-	length = count > 20 ? 20 : count;
-	if (copy_from_user(&buf[0], buffer, length))
-		return -EFAULT;
-	buf[length - 1] = '\0';	/*Ensure end string */
-	if (kstrtou8(buf, 0, &reg_val) < 0)
-		return -EINVAL;
+	int err;
+	u8 reg_val;
+	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+	if (err)
+		return err;
+
 	viafb_write_reg_mask(CR97, VIACR, reg_val, 0x0f);
 	return count;
 }

@@ -1319,17 +1314,12 @@ static int viafb_dfpl_proc_open(struct inode *inode, struct file *file)
 static ssize_t viafb_dfpl_proc_write(struct file *file,
 	const char __user *buffer, size_t count, loff_t *pos)
 {
-	char buf[20];
-	u8 reg_val = 0;
-	unsigned long length;
-	if (count < 1)
-		return -EINVAL;
-	length = count > 20 ? 20 : count;
-	if (copy_from_user(&buf[0], buffer, length))
-		return -EFAULT;
-	buf[length - 1] = '\0';	/*Ensure end string */
-	if (kstrtou8(buf, 0, &reg_val) < 0)
-		return -EINVAL;
+	int err;
+	u8 reg_val;
+	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
+	if (err)
+		return err;
+
 	viafb_write_reg_mask(CR99, VIACR, reg_val, 0x0f);
 	return count;
 }

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