sparc: copy_from_user() should not return -EFAULT
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Callers of copy_from_user() expect it to return the number of bytes
it could not copy. In no case it is supposed to return -EFAULT.
In case of a detected buffer overflow just return the requested
length. In addition one could think of a memset that would clear
the size of the target object.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/include/asm/uaccess_32.h b/arch/sparc/include/asm/uaccess_32.h
index 489d2ba..25f1d10 100644
--- a/arch/sparc/include/asm/uaccess_32.h
+++ b/arch/sparc/include/asm/uaccess_32.h
@@ -274,7 +274,7 @@
if (unlikely(sz != -1 && sz < n)) {
copy_from_user_overflow();
- return -EFAULT;
+ return n;
}
if (n && __access_ok((unsigned long) from, n))
diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h
index dbc1416..2406788 100644
--- a/arch/sparc/include/asm/uaccess_64.h
+++ b/arch/sparc/include/asm/uaccess_64.h
@@ -221,8 +221,8 @@
static inline unsigned long __must_check
copy_from_user(void *to, const void __user *from, unsigned long size)
{
- unsigned long ret = (unsigned long) -EFAULT;
int sz = __compiletime_object_size(to);
+ unsigned long ret = size;
if (likely(sz == -1 || sz >= size)) {
ret = ___copy_from_user(to, from, size);