Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm

Pull ARM fixes from Russell King:
 "A couple of fixes from Kees concerning problems he spotted with our
  user access support"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8658/1: uaccess: fix zeroing of 64-bit get_user()
  ARM: 8657/1: uaccess: consistently check object sizes
This commit is contained in:
Linus Torvalds 2017-02-18 17:36:15 -08:00
commit b92ce305fc
2 changed files with 33 additions and 13 deletions

View file

@ -478,11 +478,10 @@ extern unsigned long __must_check
arm_copy_from_user(void *to, const void __user *from, unsigned long n);
static inline unsigned long __must_check
__copy_from_user(void *to, const void __user *from, unsigned long n)
__arch_copy_from_user(void *to, const void __user *from, unsigned long n)
{
unsigned int __ua_flags;
check_object_size(to, n, false);
__ua_flags = uaccess_save_and_enable();
n = arm_copy_from_user(to, from, n);
uaccess_restore(__ua_flags);
@ -495,18 +494,15 @@ extern unsigned long __must_check
__copy_to_user_std(void __user *to, const void *from, unsigned long n);
static inline unsigned long __must_check
__copy_to_user(void __user *to, const void *from, unsigned long n)
__arch_copy_to_user(void __user *to, const void *from, unsigned long n)
{
#ifndef CONFIG_UACCESS_WITH_MEMCPY
unsigned int __ua_flags;
check_object_size(from, n, true);
__ua_flags = uaccess_save_and_enable();
n = arm_copy_to_user(to, from, n);
uaccess_restore(__ua_flags);
return n;
#else
check_object_size(from, n, true);
return arm_copy_to_user(to, from, n);
#endif
}
@ -526,25 +522,49 @@ __clear_user(void __user *addr, unsigned long n)
}
#else
#define __copy_from_user(to, from, n) (memcpy(to, (void __force *)from, n), 0)
#define __copy_to_user(to, from, n) (memcpy((void __force *)to, from, n), 0)
#define __arch_copy_from_user(to, from, n) \
(memcpy(to, (void __force *)from, n), 0)
#define __arch_copy_to_user(to, from, n) \
(memcpy((void __force *)to, from, n), 0)
#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0)
#endif
static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
static inline unsigned long __must_check
__copy_from_user(void *to, const void __user *from, unsigned long n)
{
check_object_size(to, n, false);
return __arch_copy_from_user(to, from, n);
}
static inline unsigned long __must_check
copy_from_user(void *to, const void __user *from, unsigned long n)
{
unsigned long res = n;
check_object_size(to, n, false);
if (likely(access_ok(VERIFY_READ, from, n)))
res = __copy_from_user(to, from, n);
res = __arch_copy_from_user(to, from, n);
if (unlikely(res))
memset(to + (n - res), 0, res);
return res;
}
static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
static inline unsigned long __must_check
__copy_to_user(void __user *to, const void *from, unsigned long n)
{
check_object_size(from, n, true);
return __arch_copy_to_user(to, from, n);
}
static inline unsigned long __must_check
copy_to_user(void __user *to, const void *from, unsigned long n)
{
check_object_size(from, n, true);
if (access_ok(VERIFY_WRITE, to, n))
n = __copy_to_user(to, from, n);
n = __arch_copy_to_user(to, from, n);
return n;
}

View file

@ -67,7 +67,7 @@ ENTRY(__get_user_4)
ENDPROC(__get_user_4)
ENTRY(__get_user_8)
check_uaccess r0, 8, r1, r2, __get_user_bad
check_uaccess r0, 8, r1, r2, __get_user_bad8
#ifdef CONFIG_THUMB2_KERNEL
5: TUSER(ldr) r2, [r0]
6: TUSER(ldr) r3, [r0, #4]