diff options
| author | Kees Cook <keescook@chromium.org> | 2016-06-23 15:06:53 -0700 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2016-07-26 14:41:49 -0700 |
| commit | dfd45b6103c973bfcea2341d89e36faf947dbc33 (patch) | |
| tree | 7f9a7a3069064efc667a8845ca0a263a8c620315 | |
| parent | 5b710f34e194c6b7710f69fdb5d798fdf35b98c1 (diff) | |
ARM: uaccess: Enable hardened usercopy
Enables CONFIG_HARDENED_USERCOPY checks on arm.
Based on code from PaX and grsecurity.
Signed-off-by: Kees Cook <keescook@chromium.org>
| -rw-r--r-- | arch/arm/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm/include/asm/uaccess.h | 11 |
2 files changed, 10 insertions, 2 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 90542db1220d..f56b29b3f57e 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -35,6 +35,7 @@ config ARM select HARDIRQS_SW_RESEND select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT) select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 + select HAVE_ARCH_HARDENED_USERCOPY select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU select HAVE_ARCH_MMAP_RND_BITS if MMU diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 35c9db857ebe..7fb59199c6bb 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -496,7 +496,10 @@ 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) { - unsigned int __ua_flags = uaccess_save_and_enable(); + 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); return n; @@ -511,11 +514,15 @@ static inline unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n) { #ifndef CONFIG_UACCESS_WITH_MEMCPY - unsigned int __ua_flags = uaccess_save_and_enable(); + 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 } |