Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 479 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
new file mode 100644
index 000000000..6ed40fcd8
--- /dev/null
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -0,0 +1,479 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ARCH_POWERPC_UACCESS_H
+#define _ARCH_POWERPC_UACCESS_H
+
+#include <asm/ppc_asm.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+#include <asm/extable.h>
+#include <asm/kup.h>
+
+/*
+ * The fs value determines whether argument validity checking should be
+ * performed or not.  If get_fs() == USER_DS, checking is performed, with
+ * get_fs() == KERNEL_DS, checking is bypassed.
+ *
+ * For historical reasons, these macros are grossly misnamed.
+ *
+ * The fs/ds values are now the highest legal address in the "segment".
+ * This simplifies the checking in the routines below.
+ */
+
+#define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
+
+#define KERNEL_DS	MAKE_MM_SEG(~0UL)
+#ifdef __powerpc64__
+/* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */
+#define USER_DS		MAKE_MM_SEG(TASK_SIZE_USER64 - 1)
+#else
+#define USER_DS		MAKE_MM_SEG(TASK_SIZE - 1)
+#endif
+
+#define get_ds()	(KERNEL_DS)
+#define get_fs()	(current->thread.addr_limit)
+
+static inline void set_fs(mm_segment_t fs)
+{
+	current->thread.addr_limit = fs;
+	/* On user-mode return check addr_limit (fs) is correct */
+	set_thread_flag(TIF_FSCHECK);
+}
+
+#define segment_eq(a, b)	((a).seg == (b).seg)
+
+#define user_addr_max()	(get_fs().seg)
+
+#ifdef __powerpc64__
+/*
+ * This check is sufficient because there is a large enough
+ * gap between user addresses and the kernel addresses
+ */
+#define __access_ok(addr, size, segment)	\
+	(((addr) <= (segment).seg) && ((size) <= (segment).seg))
+
+#else
+
+static inline int __access_ok(unsigned long addr, unsigned long size,
+			mm_segment_t seg)
+{
+	if (addr > seg.seg)
+		return 0;
+	return (size == 0 || size - 1 <= seg.seg - addr);
+}
+
+#endif
+
+#define access_ok(type, addr, size)		\
+	(__chk_user_ptr(addr), (void)(type),		\
+	 __access_ok((__force unsigned long)(addr), (size), get_fs()))
+
+/*
+ * These are the main single-value transfer routines.  They automatically
+ * use the right size if we just have the right pointer type.
+ *
+ * This gets kind of ugly. We want to return _two_ values in "get_user()"
+ * and yet we don't want to do any pointers, because that is too much
+ * of a performance impact. Thus we have a few rather ugly macros here,
+ * and hide all the ugliness from the user.
+ *
+ * The "__xxx" versions of the user access functions are versions that
+ * do not verify the address space, that must have been done previously
+ * with a separate "access_ok()" call (this is used when we do multiple
+ * accesses to the same area of user memory).
+ *
+ * As we use the same address space for kernel and user data on the
+ * PowerPC, we can just do these as direct assignments.  (Of course, the
+ * exception handling means that it's no longer "just"...)
+ *
+ */
+#define get_user(x, ptr) \
+	__get_user_check((x), (ptr), sizeof(*(ptr)))
+#define put_user(x, ptr) \
+	__put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
+
+#define __get_user(x, ptr) \
+	__get_user_nocheck((x), (ptr), sizeof(*(ptr)), true)
+#define __put_user(x, ptr) \
+	__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), true)
+
+#define __get_user_allowed(x, ptr) \
+	__get_user_nocheck((x), (ptr), sizeof(*(ptr)), false)
+#define __put_user_allowed(x, ptr) \
+	__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), false)
+
+#define __get_user_inatomic(x, ptr) \
+	__get_user_nosleep((x), (ptr), sizeof(*(ptr)))
+#define __put_user_inatomic(x, ptr) \
+	__put_user_nosleep((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
+
+extern long __put_user_bad(void);
+
+/*
+ * We don't tell gcc that we are accessing memory, but this is OK
+ * because we do not write to any memory gcc knows about, so there
+ * are no aliasing issues.
+ */
+#define __put_user_asm(x, addr, err, op)			\
+	__asm__ __volatile__(					\
+		"1:	" op " %1,0(%2)	# put_user\n"		\
+		"2:\n"						\
+		".section .fixup,\"ax\"\n"			\
+		"3:	li %0,%3\n"				\
+		"	b 2b\n"					\
+		".previous\n"					\
+		EX_TABLE(1b, 3b)				\
+		: "=r" (err)					\
+		: "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
+
+#ifdef __powerpc64__
+#define __put_user_asm2(x, ptr, retval)				\
+	  __put_user_asm(x, ptr, retval, "std")
+#else /* __powerpc64__ */
+#define __put_user_asm2(x, addr, err)				\
+	__asm__ __volatile__(					\
+		"1:	stw %1,0(%2)\n"				\
+		"2:	stw %1+1,4(%2)\n"			\
+		"3:\n"						\
+		".section .fixup,\"ax\"\n"			\
+		"4:	li %0,%3\n"				\
+		"	b 3b\n"					\
+		".previous\n"					\
+		EX_TABLE(1b, 4b)				\
+		EX_TABLE(2b, 4b)				\
+		: "=r" (err)					\
+		: "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
+#endif /* __powerpc64__ */
+
+#define __put_user_size_allowed(x, ptr, size, retval)		\
+do {								\
+	retval = 0;						\
+	switch (size) {						\
+	  case 1: __put_user_asm(x, ptr, retval, "stb"); break;	\
+	  case 2: __put_user_asm(x, ptr, retval, "sth"); break;	\
+	  case 4: __put_user_asm(x, ptr, retval, "stw"); break;	\
+	  case 8: __put_user_asm2(x, ptr, retval); break;	\
+	  default: __put_user_bad();				\
+	}							\
+} while (0)
+
+#define __put_user_size(x, ptr, size, retval)			\
+do {								\
+	allow_write_to_user(ptr, size);				\
+	__put_user_size_allowed(x, ptr, size, retval);		\
+	prevent_write_to_user(ptr, size);			\
+} while (0)
+
+#define __put_user_nocheck(x, ptr, size, do_allow)			\
+({								\
+	long __pu_err;						\
+	__typeof__(*(ptr)) __user *__pu_addr = (ptr);		\
+	__typeof__(*(ptr)) __pu_val = (x);			\
+	__typeof__(size) __pu_size = (size);			\
+								\
+	if (!is_kernel_addr((unsigned long)__pu_addr))		\
+		might_fault();					\
+	__chk_user_ptr(__pu_addr);				\
+	if (do_allow)								\
+		__put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err);	\
+	else									\
+		__put_user_size_allowed(__pu_val, __pu_addr, __pu_size, __pu_err); \
+								\
+	__pu_err;						\
+})
+
+#define __put_user_check(x, ptr, size)					\
+({									\
+	long __pu_err = -EFAULT;					\
+	__typeof__(*(ptr)) __user *__pu_addr = (ptr);			\
+	__typeof__(*(ptr)) __pu_val = (x);				\
+	__typeof__(size) __pu_size = (size);				\
+									\
+	might_fault();							\
+	if (access_ok(VERIFY_WRITE, __pu_addr, __pu_size))			\
+		__put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \
+									\
+	__pu_err;							\
+})
+
+#define __put_user_nosleep(x, ptr, size)			\
+({								\
+	long __pu_err;						\
+	__typeof__(*(ptr)) __user *__pu_addr = (ptr);		\
+	__typeof__(*(ptr)) __pu_val = (x);			\
+	__typeof__(size) __pu_size = (size);			\
+								\
+	__chk_user_ptr(__pu_addr);				\
+	__put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \
+								\
+	__pu_err;						\
+})
+
+
+extern long __get_user_bad(void);
+
+/*
+ * This does an atomic 128 byte aligned load from userspace.
+ * Upto caller to do enable_kernel_vmx() before calling!
+ */
+#define __get_user_atomic_128_aligned(kaddr, uaddr, err)		\
+	__asm__ __volatile__(				\
+		".machine push\n"			\
+		".machine altivec\n"			\
+		"1:	lvx  0,0,%1	# get user\n"	\
+		" 	stvx 0,0,%2	# put kernel\n"	\
+		".machine pop\n"			\
+		"2:\n"					\
+		".section .fixup,\"ax\"\n"		\
+		"3:	li %0,%3\n"			\
+		"	b 2b\n"				\
+		".previous\n"				\
+		EX_TABLE(1b, 3b)			\
+		: "=r" (err)			\
+		: "b" (uaddr), "b" (kaddr), "i" (-EFAULT), "0" (err))
+
+#define __get_user_asm(x, addr, err, op)		\
+	__asm__ __volatile__(				\
+		"1:	"op" %1,0(%2)	# get_user\n"	\
+		"2:\n"					\
+		".section .fixup,\"ax\"\n"		\
+		"3:	li %0,%3\n"			\
+		"	li %1,0\n"			\
+		"	b 2b\n"				\
+		".previous\n"				\
+		EX_TABLE(1b, 3b)			\
+		: "=r" (err), "=r" (x)			\
+		: "b" (addr), "i" (-EFAULT), "0" (err))
+
+#ifdef __powerpc64__
+#define __get_user_asm2(x, addr, err)			\
+	__get_user_asm(x, addr, err, "ld")
+#else /* __powerpc64__ */
+#define __get_user_asm2(x, addr, err)			\
+	__asm__ __volatile__(				\
+		"1:	lwz %1,0(%2)\n"			\
+		"2:	lwz %1+1,4(%2)\n"		\
+		"3:\n"					\
+		".section .fixup,\"ax\"\n"		\
+		"4:	li %0,%3\n"			\
+		"	li %1,0\n"			\
+		"	li %1+1,0\n"			\
+		"	b 3b\n"				\
+		".previous\n"				\
+		EX_TABLE(1b, 4b)			\
+		EX_TABLE(2b, 4b)			\
+		: "=r" (err), "=&r" (x)			\
+		: "b" (addr), "i" (-EFAULT), "0" (err))
+#endif /* __powerpc64__ */
+
+#define __get_user_size_allowed(x, ptr, size, retval)		\
+do {								\
+	retval = 0;						\
+	__chk_user_ptr(ptr);					\
+	if (size > sizeof(x))					\
+		(x) = __get_user_bad();				\
+	switch (size) {						\
+	case 1: __get_user_asm(x, ptr, retval, "lbz"); break;	\
+	case 2: __get_user_asm(x, ptr, retval, "lhz"); break;	\
+	case 4: __get_user_asm(x, ptr, retval, "lwz"); break;	\
+	case 8: __get_user_asm2(x, ptr, retval);  break;	\
+	default: (x) = __get_user_bad();			\
+	}							\
+} while (0)
+
+#define __get_user_size(x, ptr, size, retval)			\
+do {								\
+	allow_read_from_user(ptr, size);			\
+	__get_user_size_allowed(x, ptr, size, retval);		\
+	prevent_read_from_user(ptr, size);			\
+} while (0)
+
+/*
+ * This is a type: either unsigned long, if the argument fits into
+ * that type, or otherwise unsigned long long.
+ */
+#define __long_type(x) \
+	__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
+
+#define __get_user_nocheck(x, ptr, size, do_allow)			\
+({								\
+	long __gu_err;						\
+	__long_type(*(ptr)) __gu_val;				\
+	__typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
+	__typeof__(size) __gu_size = (size);			\
+								\
+	__chk_user_ptr(__gu_addr);				\
+	if (!is_kernel_addr((unsigned long)__gu_addr))		\
+		might_fault();					\
+	barrier_nospec();					\
+	if (do_allow)								\
+		__get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err);	\
+	else									\
+		__get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \
+	(x) = (__typeof__(*(ptr)))__gu_val;			\
+								\
+	__gu_err;						\
+})
+
+#define __get_user_check(x, ptr, size)					\
+({									\
+	long __gu_err = -EFAULT;					\
+	__long_type(*(ptr)) __gu_val = 0;				\
+	__typeof__(*(ptr)) __user *__gu_addr = (ptr);		\
+	__typeof__(size) __gu_size = (size);				\
+									\
+	might_fault();							\
+	if (access_ok(VERIFY_READ, __gu_addr, __gu_size)) {		\
+		barrier_nospec();					\
+		__get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \
+	}								\
+	(x) = (__force __typeof__(*(ptr)))__gu_val;				\
+									\
+	__gu_err;							\
+})
+
+#define __get_user_nosleep(x, ptr, size)			\
+({								\
+	long __gu_err;						\
+	__long_type(*(ptr)) __gu_val;				\
+	__typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
+	__typeof__(size) __gu_size = (size);			\
+								\
+	__chk_user_ptr(__gu_addr);				\
+	barrier_nospec();					\
+	__get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \
+	(x) = (__force __typeof__(*(ptr)))__gu_val;			\
+								\
+	__gu_err;						\
+})
+
+
+/* more complex routines */
+
+extern unsigned long __copy_tofrom_user(void __user *to,
+		const void __user *from, unsigned long size);
+
+#ifdef __powerpc64__
+static inline unsigned long
+raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
+{
+	unsigned long ret;
+
+	barrier_nospec();
+	allow_user_access(to, from, n);
+	ret = __copy_tofrom_user(to, from, n);
+	prevent_user_access(to, from, n);
+	return ret;
+}
+#endif /* __powerpc64__ */
+
+static inline unsigned long raw_copy_from_user(void *to,
+		const void __user *from, unsigned long n)
+{
+	unsigned long ret;
+	if (__builtin_constant_p(n) && (n <= 8)) {
+		ret = 1;
+
+		switch (n) {
+		case 1:
+			barrier_nospec();
+			__get_user_size(*(u8 *)to, from, 1, ret);
+			break;
+		case 2:
+			barrier_nospec();
+			__get_user_size(*(u16 *)to, from, 2, ret);
+			break;
+		case 4:
+			barrier_nospec();
+			__get_user_size(*(u32 *)to, from, 4, ret);
+			break;
+		case 8:
+			barrier_nospec();
+			__get_user_size(*(u64 *)to, from, 8, ret);
+			break;
+		}
+		if (ret == 0)
+			return 0;
+	}
+
+	barrier_nospec();
+	allow_read_from_user(from, n);
+	ret = __copy_tofrom_user((__force void __user *)to, from, n);
+	prevent_read_from_user(from, n);
+	return ret;
+}
+
+static inline unsigned long
+raw_copy_to_user_allowed(void __user *to, const void *from, unsigned long n)
+{
+	if (__builtin_constant_p(n) && (n <= 8)) {
+		unsigned long ret = 1;
+
+		switch (n) {
+		case 1:
+			__put_user_size_allowed(*(u8 *)from, (u8 __user *)to, 1, ret);
+			break;
+		case 2:
+			__put_user_size_allowed(*(u16 *)from, (u16 __user *)to, 2, ret);
+			break;
+		case 4:
+			__put_user_size_allowed(*(u32 *)from, (u32 __user *)to, 4, ret);
+			break;
+		case 8:
+			__put_user_size_allowed(*(u64 *)from, (u64 __user *)to, 8, ret);
+			break;
+		}
+		if (ret == 0)
+			return 0;
+	}
+
+	return __copy_tofrom_user(to, (__force const void __user *)from, n);
+}
+
+static inline unsigned long
+raw_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+	unsigned long ret;
+
+	allow_write_to_user(to, n);
+	ret = raw_copy_to_user_allowed(to, from, n);
+	prevent_write_to_user(to, n);
+	return ret;
+}
+
+unsigned long __arch_clear_user(void __user *addr, unsigned long size);
+
+static inline unsigned long clear_user(void __user *addr, unsigned long size)
+{
+	unsigned long ret = size;
+	might_fault();
+	if (likely(access_ok(VERIFY_WRITE, addr, size))) {
+		allow_write_to_user(addr, size);
+		ret = __arch_clear_user(addr, size);
+		prevent_write_to_user(addr, size);
+	}
+	return ret;
+}
+
+static inline unsigned long __clear_user(void __user *addr, unsigned long size)
+{
+	return clear_user(addr, size);
+}
+
+extern long strncpy_from_user(char *dst, const char __user *src, long count);
+extern __must_check long strnlen_user(const char __user *str, long n);
+
+extern long __copy_from_user_flushcache(void *dst, const void __user *src,
+		unsigned size);
+extern void memcpy_page_flushcache(char *to, struct page *page, size_t offset,
+			   size_t len);
+
+#define user_access_begin(type, ptr, len) access_ok(type, ptr, len)
+#define user_access_end()		  prevent_user_access(NULL, NULL, ~0ul)
+
+#define unsafe_op_wrap(op, err) do { if (unlikely(op)) goto err; } while (0)
+#define unsafe_get_user(x, p, e) unsafe_op_wrap(__get_user_allowed(x, p), e)
+#define unsafe_put_user(x, p, e) unsafe_op_wrap(__put_user_allowed(x, p), e)
+#define unsafe_copy_to_user(d, s, l, e) \
+	unsafe_op_wrap(raw_copy_to_user_allowed(d, s, l), e)
+
+#endif	/* _ARCH_POWERPC_UACCESS_H */