[PATCH v10 7/7] powerpc: add machine check safe copy_to_user
From: Santosh Sivaraj <hidden>
Date: 2019-08-15 00:40:29
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Use memcpy_mcsafe() implementation to define copy_to_user_mcsafe() Signed-off-by: Santosh Sivaraj <redacted> --- 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 77f6ebf97113..4316e36095a2 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 if PPC64 + 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)
--
2.21.0