From: Yang Shi yang.shi@linaro.org
commit bffe1baff5d57521b0c41b6997c41ff1993e9818 upstream.
The upstream commit 1771c6e1a567ea0ba2cccc0a4ffe68a1419fd8ef ("x86/kasan: instrument user memory access API") added KASAN instrument to x86 user memory access API, so added such instrument to ARM64 too.
Define __copy_to/from_user in C in order to add kasan_check_read/write call, rename assembly implementation to __arch_copy_to/from_user.
Tested by test_kasan module.
Acked-by: Andrey Ryabinin aryabinin@virtuozzo.com Reviewed-by: Mark Rutland mark.rutland@arm.com Tested-by: Mark Rutland mark.rutland@arm.com Signed-off-by: Yang Shi yang.shi@linaro.org Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- arch/arm64/include/asm/uaccess.h | 25 +++++++++++++++++++++---- arch/arm64/kernel/arm64ksyms.c | 4 ++-- arch/arm64/lib/copy_from_user.S | 4 ++-- arch/arm64/lib/copy_to_user.S | 4 ++-- 4 files changed, 27 insertions(+), 10 deletions(-)
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index a34324436ce1..693a0d784534 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -22,6 +22,7 @@ * User space memory access functions */ #include <linux/bitops.h> +#include <linux/kasan-checks.h> #include <linux/string.h> #include <linux/thread_info.h>
@@ -300,15 +301,29 @@ do { \
#define put_user __put_user
-extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n); -extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n); +extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); extern unsigned long __must_check __copy_in_user(void __user *to, const void __user *from, unsigned long n); extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
+static inline unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n) +{ + kasan_check_write(to, n); + return __arch_copy_from_user(to, from, n); +} + +static inline unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n) +{ + kasan_check_read(from, n); + return __arch_copy_to_user(to, from, n); +} + static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n) { + kasan_check_write(to, n); + if (access_ok(VERIFY_READ, from, n)) - n = __copy_from_user(to, from, n); + n = __arch_copy_from_user(to, from, n); else /* security hole - plug it */ memset(to, 0, n); return n; @@ -316,8 +331,10 @@ static inline unsigned long __must_check copy_from_user(void *to, const void __u
static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n) { + kasan_check_read(from, n); + if (access_ok(VERIFY_WRITE, to, n)) - n = __copy_to_user(to, from, n); + n = __arch_copy_to_user(to, from, n); return n; }
diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c index 3b6d8cc9dfe0..c654df05b7d7 100644 --- a/arch/arm64/kernel/arm64ksyms.c +++ b/arch/arm64/kernel/arm64ksyms.c @@ -33,8 +33,8 @@ EXPORT_SYMBOL(copy_page); EXPORT_SYMBOL(clear_page);
/* user mem (segment) */ -EXPORT_SYMBOL(__copy_from_user); -EXPORT_SYMBOL(__copy_to_user); +EXPORT_SYMBOL(__arch_copy_from_user); +EXPORT_SYMBOL(__arch_copy_to_user); EXPORT_SYMBOL(__clear_user); EXPORT_SYMBOL(__copy_in_user);
diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 4699cd74f87e..281e75db899a 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -66,7 +66,7 @@ .endm
end .req x5 -ENTRY(__copy_from_user) +ENTRY(__arch_copy_from_user) ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \ CONFIG_ARM64_PAN) add end, x0, x2 @@ -75,7 +75,7 @@ ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \ CONFIG_ARM64_PAN) mov x0, #0 // Nothing to copy ret -ENDPROC(__copy_from_user) +ENDPROC(__arch_copy_from_user)
.section .fixup,"ax" .align 2 diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 7512bbbc07ac..db4d187de61f 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -65,7 +65,7 @@ .endm
end .req x5 -ENTRY(__copy_to_user) +ENTRY(__arch_copy_to_user) ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \ CONFIG_ARM64_PAN) add end, x0, x2 @@ -74,7 +74,7 @@ ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \ CONFIG_ARM64_PAN) mov x0, #0 ret -ENDPROC(__copy_to_user) +ENDPROC(__arch_copy_to_user)
.section .fixup,"ax" .align 2