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| author | Michael Ellerman <mpe@ellerman.id.au> | 2018-04-24 07:15:58 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-06-03 13:43:45 +0300 |
| commit | ddf35cf3764b5a182b178105f57515b42e2634f8 (patch) | |
| tree | edebc20a9689231fd62d857d9a9e51f9bf3850c3 /arch/powerpc/include/asm/uaccess.h | |
| parent | cb3d6759a93c6d0aea1c10deb6d00e111c29c19c (diff) | |
| download | linux-ddf35cf3764b5a182b178105f57515b42e2634f8.tar.xz | |
powerpc: Use barrier_nospec in copy_from_user()
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>
Diffstat (limited to 'arch/powerpc/include/asm/uaccess.h')
| -rw-r--r-- | arch/powerpc/include/asm/uaccess.h | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index abba80f8ff04..468653ce844c 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -258,6 +258,7 @@ 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; \ @@ -269,8 +270,10 @@ do { \ unsigned long __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; \ }) @@ -281,6 +284,7 @@ do { \ unsigned long __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; \ @@ -308,15 +312,19 @@ 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; } @@ -324,6 +332,7 @@ static inline unsigned long raw_copy_from_user(void *to, return 0; } + barrier_nospec(); return __copy_tofrom_user((__force void __user *)to, from, n); } |