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authorDavid S. Miller <davem@davemloft.net>2011-12-23 23:13:56 +0100
committerDavid S. Miller <davem@davemloft.net>2011-12-23 23:13:56 +0100
commitabb434cb0539fb355c1c921f8fd761efbbac3462 (patch)
tree24a7d99ec161f8fd4dc9ff03c9c4cc93be883ce6 /drivers/oprofile/oprofilefs.c
parentnetem: loss model API sizes (diff)
parentMerge branch 'nf' of git://1984.lsi.us.es/net (diff)
downloadlinux-abb434cb0539fb355c1c921f8fd761efbbac3462.tar.xz
linux-abb434cb0539fb355c1c921f8fd761efbbac3462.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: net/bluetooth/l2cap_core.c Just two overlapping changes, one added an initialization of a local variable, and another change added a new local variable. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/oprofile/oprofilefs.c')
-rw-r--r--drivers/oprofile/oprofilefs.c11
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/oprofile/oprofilefs.c b/drivers/oprofile/oprofilefs.c
index d0de6cc2d7a5..2f0aa0f700e6 100644
--- a/drivers/oprofile/oprofilefs.c
+++ b/drivers/oprofile/oprofilefs.c
@@ -60,6 +60,13 @@ ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user *buf, size_t cou
}
+/*
+ * Note: If oprofilefs_ulong_from_user() returns 0, then *val remains
+ * unchanged and might be uninitialized. This follows write syscall
+ * implementation when count is zero: "If count is zero ... [and if]
+ * no errors are detected, 0 will be returned without causing any
+ * other effect." (man 2 write)
+ */
int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_t count)
{
char tmpbuf[TMPBUFSIZE];
@@ -79,7 +86,7 @@ int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_
raw_spin_lock_irqsave(&oprofilefs_lock, flags);
*val = simple_strtoul(tmpbuf, NULL, 0);
raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
- return 0;
+ return count;
}
@@ -99,7 +106,7 @@ static ssize_t ulong_write_file(struct file *file, char const __user *buf, size_
return -EINVAL;
retval = oprofilefs_ulong_from_user(&value, buf, count);
- if (retval)
+ if (retval <= 0)
return retval;
retval = oprofile_set_ulong(file->private_data, value);