[PATCH v4 09/12] sparc/uaccess: Enable hardened usercopy
From: Kees Cook <hidden>
Date: 2016-07-20 20:27:43
Also in:
linux-arch, linux-arm-kernel, linux-mm, lkml, sparclinux
Subsystem:
sparc + ultrasparc (sparc/sparc64), the rest · Maintainers:
"David S. Miller", Andreas Larsson, Linus Torvalds
Enables CONFIG_HARDENED_USERCOPY checks on sparc. Based on code from PaX and grsecurity. Signed-off-by: Kees Cook <redacted> --- arch/sparc/Kconfig | 1 + arch/sparc/include/asm/uaccess_32.h | 14 ++++++++++---- arch/sparc/include/asm/uaccess_64.h | 11 +++++++++-- 3 files changed, 20 insertions(+), 6 deletions(-)
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 546293d9e6c5..59b09600dd32 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig@@ -43,6 +43,7 @@ config SPARC select OLD_SIGSUSPEND select ARCH_HAS_SG_CHAIN select CPU_NO_EFFICIENT_FFS + select HAVE_ARCH_HARDENED_USERCOPY config SPARC32 def_bool !64BIT
diff --git a/arch/sparc/include/asm/uaccess_32.h b/arch/sparc/include/asm/uaccess_32.h
index 57aca2792d29..341a5a133f48 100644
--- a/arch/sparc/include/asm/uaccess_32.h
+++ b/arch/sparc/include/asm/uaccess_32.h@@ -248,22 +248,28 @@ unsigned long __copy_user(void __user *to, const void __user *from, unsigned lon static inline unsigned long copy_to_user(void __user *to, const void *from, unsigned long n) { - if (n && __access_ok((unsigned long) to, n)) + if (n && __access_ok((unsigned long) to, n)) { + if (!__builtin_constant_p(n)) + check_object_size(from, n, true); return __copy_user(to, (__force void __user *) from, n); - else + } else return n; } static inline unsigned long __copy_to_user(void __user *to, const void *from, unsigned long n) { + if (!__builtin_constant_p(n)) + check_object_size(from, n, true); return __copy_user(to, (__force void __user *) from, n); } static inline unsigned long copy_from_user(void *to, const void __user *from, unsigned long n) { - if (n && __access_ok((unsigned long) from, n)) + if (n && __access_ok((unsigned long) from, n)) { + if (!__builtin_constant_p(n)) + check_object_size(to, n, false); return __copy_user((__force void __user *) to, from, n); - else + } else return n; }
diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h
index e9a51d64974d..8bda94fab8e8 100644
--- a/arch/sparc/include/asm/uaccess_64.h
+++ b/arch/sparc/include/asm/uaccess_64.h@@ -210,8 +210,12 @@ unsigned long copy_from_user_fixup(void *to, const void __user *from, static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long size) { - unsigned long ret = ___copy_from_user(to, from, size); + unsigned long ret; + if (!__builtin_constant_p(size)) + check_object_size(to, size, false); + + ret = ___copy_from_user(to, from, size); if (unlikely(ret)) ret = copy_from_user_fixup(to, from, size);
@@ -227,8 +231,11 @@ unsigned long copy_to_user_fixup(void __user *to, const void *from, static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long size) { - unsigned long ret = ___copy_to_user(to, from, size); + unsigned long ret; + if (!__builtin_constant_p(size)) + check_object_size(from, size, true); + ret = ___copy_to_user(to, from, size); if (unlikely(ret)) ret = copy_to_user_fixup(to, from, size); return ret;
--
2.7.4