summaryrefslogtreecommitdiff
path: root/arch/arm/lib
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/lib')
-rw-r--r--arch/arm/lib/clear_user.S4
-rw-r--r--arch/arm/lib/uaccess_with_memcpy.c29
2 files changed, 27 insertions, 6 deletions
diff --git a/arch/arm/lib/clear_user.S b/arch/arm/lib/clear_user.S
index 970d6c043..e936352cc 100644
--- a/arch/arm/lib/clear_user.S
+++ b/arch/arm/lib/clear_user.S
@@ -9,6 +9,7 @@
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
+#include <asm/unwind.h>
.text
@@ -20,6 +21,8 @@
*/
ENTRY(__clear_user_std)
WEAK(arm_clear_user)
+UNWIND(.fnstart)
+UNWIND(.save {r1, lr})
stmfd sp!, {r1, lr}
mov r2, #0
cmp r1, #4
@@ -44,6 +47,7 @@ WEAK(arm_clear_user)
USER( strnebt r2, [r0])
mov r0, #0
ldmfd sp!, {r1, pc}
+UNWIND(.fnend)
ENDPROC(arm_clear_user)
ENDPROC(__clear_user_std)
diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c
index d72b90905..588bbc288 100644
--- a/arch/arm/lib/uaccess_with_memcpy.c
+++ b/arch/arm/lib/uaccess_with_memcpy.c
@@ -88,6 +88,7 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
static unsigned long noinline
__copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
{
+ unsigned long ua_flags;
int atomic;
if (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
@@ -118,7 +119,9 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
if (tocopy > n)
tocopy = n;
+ ua_flags = uaccess_save_and_enable();
memcpy((void *)to, from, tocopy);
+ uaccess_restore(ua_flags);
to += tocopy;
from += tocopy;
n -= tocopy;
@@ -145,14 +148,21 @@ arm_copy_to_user(void __user *to, const void *from, unsigned long n)
* With frame pointer disabled, tail call optimization kicks in
* as well making this test almost invisible.
*/
- if (n < 64)
- return __copy_to_user_std(to, from, n);
- return __copy_to_user_memcpy(to, from, n);
+ if (n < 64) {
+ unsigned long ua_flags = uaccess_save_and_enable();
+ n = __copy_to_user_std(to, from, n);
+ uaccess_restore(ua_flags);
+ } else {
+ n = __copy_to_user_memcpy(to, from, n);
+ }
+ return n;
}
static unsigned long noinline
__clear_user_memset(void __user *addr, unsigned long n)
{
+ unsigned long ua_flags;
+
if (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
memset((void *)addr, 0, n);
return 0;
@@ -175,7 +185,9 @@ __clear_user_memset(void __user *addr, unsigned long n)
if (tocopy > n)
tocopy = n;
+ ua_flags = uaccess_save_and_enable();
memset((void *)addr, 0, tocopy);
+ uaccess_restore(ua_flags);
addr += tocopy;
n -= tocopy;
@@ -193,9 +205,14 @@ out:
unsigned long arm_clear_user(void __user *addr, unsigned long n)
{
/* See rational for this in __copy_to_user() above. */
- if (n < 64)
- return __clear_user_std(addr, n);
- return __clear_user_memset(addr, n);
+ if (n < 64) {
+ unsigned long ua_flags = uaccess_save_and_enable();
+ n = __clear_user_std(addr, n);
+ uaccess_restore(ua_flags);
+ } else {
+ n = __clear_user_memset(addr, n);
+ }
+ return n;
}
#if 0