From 42ac26d253ebe7a5f409443f2fbd239d66b65f57 Mon Sep 17 00:00:00 2001 From: Santosh Sivaraj Date: Tue, 20 Aug 2019 13:43:52 +0530 Subject: [PATCH] powerpc: add machine check safe copy_to_user Use memcpy_mcsafe() implementation to define copy_to_user_mcsafe() Signed-off-by: Santosh Sivaraj Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190820081352.8641-8-santosh@fossix.org --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/uaccess.h | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 9bc8ac5b8c96..78f52030e76a 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -137,6 +137,7 @@ config PPC select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !RELOCATABLE && !HIBERNATION) select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UACCESS_FLUSHCACHE + select ARCH_HAS_UACCESS_MCSAFE if PPC64 select ARCH_HAS_UBSAN_SANITIZE_ALL select ARCH_HAVE_NMI_SAFE_CMPXCHG select ARCH_KEEP_MEMBLOCK diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index 8b03eb44e876..15002b51ff18 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -387,6 +387,20 @@ static inline unsigned long raw_copy_to_user(void __user *to, return ret; } +static __always_inline unsigned long __must_check +copy_to_user_mcsafe(void __user *to, const void *from, unsigned long n) +{ + if (likely(check_copy_size(from, n, true))) { + if (access_ok(to, n)) { + allow_write_to_user(to, n); + n = memcpy_mcsafe((void *)to, from, n); + prevent_write_to_user(to, n); + } + } + + return n; +} + extern unsigned long __clear_user(void __user *addr, unsigned long size); static inline unsigned long clear_user(void __user *addr, unsigned long size) -- 2.45.2