summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMichael Ellerman <mpe@ellerman.id.au>2019-03-29 22:25:52 +1100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-04-03 06:25:12 +0200
commit3692ca6ff3ee470951c91c788447ed38e6f8dd7c (patch)
tree0ef84d6f2c322df691532f8c9aece4eb0459d1f3
parentae082ed4702e31ed833b7b40b1afe4ce11adb6b4 (diff)
downloadlinux-stable-3692ca6ff3ee470951c91c788447ed38e6f8dd7c.tar.gz
linux-stable-3692ca6ff3ee470951c91c788447ed38e6f8dd7c.tar.bz2
linux-stable-3692ca6ff3ee470951c91c788447ed38e6f8dd7c.zip
powerpc: Use barrier_nospec in copy_from_user()
commit ddf35cf3764b5a182b178105f57515b42e2634f8 upstream. Based on the x86 commit doing the same. See commit 304ec1b05031 ("x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec") and b3bbfb3fb5d2 ("x86: Introduce __uaccess_begin_nospec() and uaccess_try_nospec") for more detail. In all cases we are ordering the load from the potentially user-controlled pointer vs a previous branch based on an access_ok() check or similar. Base on a patch from Michal Suchanek. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/powerpc/include/asm/uaccess.h11
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index cf26e62b268d..bd6d0fb5be9f 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -238,6 +238,7 @@ do { \
__chk_user_ptr(ptr); \
if (!is_kernel_addr((unsigned long)__gu_addr)) \
might_fault(); \
+ barrier_nospec(); \
__get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
@@ -249,8 +250,10 @@ do { \
__long_type(*(ptr)) __gu_val = 0; \
const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
might_fault(); \
- if (access_ok(VERIFY_READ, __gu_addr, (size))) \
+ if (access_ok(VERIFY_READ, __gu_addr, (size))) { \
+ barrier_nospec(); \
__get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
+ } \
(x) = (__force __typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
@@ -261,6 +264,7 @@ do { \
__long_type(*(ptr)) __gu_val; \
const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
__chk_user_ptr(ptr); \
+ barrier_nospec(); \
__get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
(x) = (__force __typeof__(*(ptr)))__gu_val; \
__gu_err; \
@@ -288,15 +292,19 @@ static inline unsigned long raw_copy_from_user(void *to,
switch (n) {
case 1:
+ barrier_nospec();
__get_user_size(*(u8 *)to, from, 1, ret);
break;
case 2:
+ barrier_nospec();
__get_user_size(*(u16 *)to, from, 2, ret);
break;
case 4:
+ barrier_nospec();
__get_user_size(*(u32 *)to, from, 4, ret);
break;
case 8:
+ barrier_nospec();
__get_user_size(*(u64 *)to, from, 8, ret);
break;
}
@@ -304,6 +312,7 @@ static inline unsigned long raw_copy_from_user(void *to,
return 0;
}
+ barrier_nospec();
return __copy_tofrom_user((__force void __user *)to, from, n);
}