[PATCH 02/14] sysfs: fix error handling in binattr write()

Tejun Heo
2007-04-07T08:23:55Z

Error handling in fs/sysfs/bin.c:write() was wrong because size_t
count is used to receive return value from flush_write() which is
negative on failure.

This patch updates write() such that int variable is used instead.
read() is updated the same way for consistency.

Signed-off-by: Tejun Heo <htejun@gmail.com>
---
fs/sysfs/bin.c | 21 ++++++++-------------
1 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index d3b9f5f..8273dd6 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -33,16 +33,13 @@ fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
}

static ssize_t
-read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
+read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
{
char *buffer = file->private_data;
struct dentry *dentry = file->f_path.dentry;
int size = dentry->d_inode->i_size;
loff_t offs = *off;
- int ret;
-
- if (count > PAGE_SIZE)
- count = PAGE_SIZE;
+ int count = min_t(size_t, bytes, PAGE_SIZE);

if (size) {
if (offs > size)
@@ -51,10 +48,9 @@ read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
count = size - offs;
}

- ret = fill_read(dentry, buffer, offs, count);
- if (ret < 0)
- return ret;
- count = ret;
+ count = fill_read(dentry, buffer, offs, count);
+ if (count < 0)
+ return count;

if (copy_to_user(userbuf, buffer, count))
return -EFAULT;
@@ -78,16 +74,15 @@ flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
return attr->write(kobj, buffer, offset, count);
}

-static ssize_t write(struct file * file, const char __user * userbuf,
- size_t count, loff_t * off)
+static ssize_t write(struct file *file, const char __user *userbuf,
+ size_t bytes, loff_t *off)
{
char *buffer = file->private_data;
struct dentry *dentry = file->f_path.dentry;
int size = dentry->d_inode->i_size;
loff_t offs = *off;
+ int count = min_t(size_t, bytes, PAGE_SIZE);

- if (count > PAGE_SIZE)
- count = PAGE_SIZE;
if (size) {
if (offs > size)
return 0;
--
1.5.0.3