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authorLinus Torvalds <torvalds@linux-foundation.org>2015-12-16 10:57:24 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-12-16 10:57:24 -0800
commita5e90b1b075f89f084047628d4ef181aded0bbfb (patch)
treeda0010e547be7bf0f3b2bac9d7c74015e5e8662f /arch/arm/lib/uaccess_with_memcpy.c
parentedb42dc7bc0da0125ceacab810a553ce1f0cac8d (diff)
parent34bfbae33ae84107d0c257edd6c6a8689a09be26 (diff)
downloadtalos-op-linux-a5e90b1b075f89f084047628d4ef181aded0bbfb.tar.gz
talos-op-linux-a5e90b1b075f89f084047628d4ef181aded0bbfb.zip
Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King: "Further ARM fixes: - Anson Huang noticed that we were corrupting a register we shouldn't be during suspend on some CPUs. - Shengjiu Wang spotted a bug in the 'swp' instruction emulation. - Will Deacon fixed a bug in the ASID allocator. - Laura Abbott fixed the kernel permission protection to apply to all threads running in the system. - I've fixed two bugs with the domain access control register handling, one to do with printing an appropriate value at oops time, and the other to further fix the uaccess_with_memcpy code" * 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: ARM: 8475/1: SWP emulation: Restore original *data when failed ARM: 8471/1: need to save/restore arm register(r11) when it is corrupted ARM: fix uaccess_with_memcpy() with SW_DOMAIN_PAN ARM: report proper DACR value in oops dumps ARM: 8464/1: Update all mm structures with section adjustments ARM: 8465/1: mm: keep reserved ASIDs in sync with mm after multiple rollovers
Diffstat (limited to 'arch/arm/lib/uaccess_with_memcpy.c')
-rw-r--r--arch/arm/lib/uaccess_with_memcpy.c29
1 files changed, 23 insertions, 6 deletions
diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c
index d72b90905132..588bbc288396 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
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