4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mark Rutland mark.rutland@arm.com
From: Will Deacon will.deacon@arm.com
commit f71c2ffcb20dd8626880747557014bb9a61eb90e upstream.
Like we've done for get_user and put_user, ensure that user pointers are masked before invoking the underlying __arch_{clear,copy_*}_user operations.
Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com [v4.9: fixup for v4.9-style uaccess primitives] Signed-off-by: Mark Rutland mark.rutland@arm.com [v4.9 backport] Tested-by: Greg Hackmann ghackmann@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/include/asm/uaccess.h | 18 ++++++++++-------- arch/arm64/kernel/arm64ksyms.c | 4 ++-- arch/arm64/lib/clear_user.S | 6 +++--- arch/arm64/lib/copy_in_user.S | 4 ++-- 4 files changed, 17 insertions(+), 15 deletions(-)
--- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -313,21 +313,20 @@ do { \
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); +extern unsigned long __must_check __arch_copy_in_user(void __user *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) { kasan_check_write(to, n); check_object_size(to, n, false); - return __arch_copy_from_user(to, from, n); + return __arch_copy_from_user(to, __uaccess_mask_ptr(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); check_object_size(from, n, true); - return __arch_copy_to_user(to, from, n); + return __arch_copy_to_user(__uaccess_mask_ptr(to), from, n); }
static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n) @@ -355,22 +354,25 @@ static inline unsigned long __must_check return n; }
-static inline unsigned long __must_check copy_in_user(void __user *to, const void __user *from, unsigned long n) +static inline unsigned long __must_check __copy_in_user(void __user *to, const void __user *from, unsigned long n) { if (access_ok(VERIFY_READ, from, n) && access_ok(VERIFY_WRITE, to, n)) - n = __copy_in_user(to, from, n); + n = __arch_copy_in_user(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n); return n; } +#define copy_in_user __copy_in_user
#define __copy_to_user_inatomic __copy_to_user #define __copy_from_user_inatomic __copy_from_user
-static inline unsigned long __must_check clear_user(void __user *to, unsigned long n) +extern unsigned long __must_check __arch_clear_user(void __user *to, unsigned long n); +static inline unsigned long __must_check __clear_user(void __user *to, unsigned long n) { if (access_ok(VERIFY_WRITE, to, n)) - n = __clear_user(__uaccess_mask_ptr(to), n); + n = __arch_clear_user(__uaccess_mask_ptr(to), n); return n; } +#define clear_user __clear_user
extern long strncpy_from_user(char *dest, const char __user *src, long count);
--- a/arch/arm64/kernel/arm64ksyms.c +++ b/arch/arm64/kernel/arm64ksyms.c @@ -37,8 +37,8 @@ EXPORT_SYMBOL(clear_page); /* user mem (segment) */ EXPORT_SYMBOL(__arch_copy_from_user); EXPORT_SYMBOL(__arch_copy_to_user); -EXPORT_SYMBOL(__clear_user); -EXPORT_SYMBOL(__copy_in_user); +EXPORT_SYMBOL(__arch_clear_user); +EXPORT_SYMBOL(__arch_copy_in_user);
/* physical memory */ EXPORT_SYMBOL(memstart_addr); --- a/arch/arm64/lib/clear_user.S +++ b/arch/arm64/lib/clear_user.S @@ -24,7 +24,7 @@
.text
-/* Prototype: int __clear_user(void *addr, size_t sz) +/* Prototype: int __arch_clear_user(void *addr, size_t sz) * Purpose : clear some user memory * Params : addr - user memory address to clear * : sz - number of bytes to clear @@ -32,7 +32,7 @@ * * Alignment fixed up by hardware. */ -ENTRY(__clear_user) +ENTRY(__arch_clear_user) ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ CONFIG_ARM64_PAN) mov x2, x1 // save the size for fixup return @@ -57,7 +57,7 @@ uao_user_alternative 9f, strb, sttrb, wz ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ CONFIG_ARM64_PAN) ret -ENDPROC(__clear_user) +ENDPROC(__arch_clear_user)
.section .fixup,"ax" .align 2 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -67,7 +67,7 @@ .endm
end .req x5 -ENTRY(__copy_in_user) +ENTRY(__arch_copy_in_user) ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ CONFIG_ARM64_PAN) add end, x0, x2 @@ -76,7 +76,7 @@ ALTERNATIVE("nop", __stringify(SET_PSTAT CONFIG_ARM64_PAN) mov x0, #0 ret -ENDPROC(__copy_in_user) +ENDPROC(__arch_copy_in_user)
.section .fixup,"ax" .align 2