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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /include/asm-generic/uaccess.h
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/asm-generic/uaccess.h')
-rw-r--r--include/asm-generic/uaccess.h314
1 files changed, 314 insertions, 0 deletions
diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
new file mode 100644
index 000000000..4973328f3
--- /dev/null
+++ b/include/asm-generic/uaccess.h
@@ -0,0 +1,314 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_GENERIC_UACCESS_H
+#define __ASM_GENERIC_UACCESS_H
+
+/*
+ * User space memory access functions, these should work
+ * on any machine that has kernel and user data in the same
+ * address space, e.g. all NOMMU machines.
+ */
+#include <linux/string.h>
+
+#ifdef CONFIG_UACCESS_MEMCPY
+#include <asm/unaligned.h>
+
+static __always_inline int
+__get_user_fn(size_t size, const void __user *from, void *to)
+{
+ BUILD_BUG_ON(!__builtin_constant_p(size));
+
+ switch (size) {
+ case 1:
+ *(u8 *)to = get_unaligned((u8 __force *)from);
+ return 0;
+ case 2:
+ *(u16 *)to = get_unaligned((u16 __force *)from);
+ return 0;
+ case 4:
+ *(u32 *)to = get_unaligned((u32 __force *)from);
+ return 0;
+ case 8:
+ *(u64 *)to = get_unaligned((u64 __force *)from);
+ return 0;
+ default:
+ BUILD_BUG();
+ return 0;
+ }
+
+}
+#define __get_user_fn(sz, u, k) __get_user_fn(sz, u, k)
+
+static __always_inline int
+__put_user_fn(size_t size, void __user *to, void *from)
+{
+ BUILD_BUG_ON(!__builtin_constant_p(size));
+
+ switch (size) {
+ case 1:
+ put_unaligned(*(u8 *)from, (u8 __force *)to);
+ return 0;
+ case 2:
+ put_unaligned(*(u16 *)from, (u16 __force *)to);
+ return 0;
+ case 4:
+ put_unaligned(*(u32 *)from, (u32 __force *)to);
+ return 0;
+ case 8:
+ put_unaligned(*(u64 *)from, (u64 __force *)to);
+ return 0;
+ default:
+ BUILD_BUG();
+ return 0;
+ }
+}
+#define __put_user_fn(sz, u, k) __put_user_fn(sz, u, k)
+
+#define __get_kernel_nofault(dst, src, type, err_label) \
+do { \
+ *((type *)dst) = get_unaligned((type *)(src)); \
+ if (0) /* make sure the label looks used to the compiler */ \
+ goto err_label; \
+} while (0)
+
+#define __put_kernel_nofault(dst, src, type, err_label) \
+do { \
+ put_unaligned(*((type *)src), (type *)(dst)); \
+ if (0) /* make sure the label looks used to the compiler */ \
+ goto err_label; \
+} while (0)
+
+#define HAVE_GET_KERNEL_NOFAULT 1
+
+static inline __must_check unsigned long
+raw_copy_from_user(void *to, const void __user * from, unsigned long n)
+{
+ memcpy(to, (const void __force *)from, n);
+ return 0;
+}
+
+static inline __must_check unsigned long
+raw_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ memcpy((void __force *)to, from, n);
+ return 0;
+}
+#define INLINE_COPY_FROM_USER
+#define INLINE_COPY_TO_USER
+#endif /* CONFIG_UACCESS_MEMCPY */
+
+#ifdef CONFIG_SET_FS
+#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
+
+#ifndef KERNEL_DS
+#define KERNEL_DS MAKE_MM_SEG(~0UL)
+#endif
+
+#ifndef USER_DS
+#define USER_DS MAKE_MM_SEG(TASK_SIZE - 1)
+#endif
+
+#ifndef get_fs
+#define get_fs() (current_thread_info()->addr_limit)
+
+static inline void set_fs(mm_segment_t fs)
+{
+ current_thread_info()->addr_limit = fs;
+}
+#endif
+
+#ifndef uaccess_kernel
+#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg)
+#endif
+#endif /* CONFIG_SET_FS */
+
+#define access_ok(addr, size) __access_ok((unsigned long)(addr),(size))
+
+/*
+ * The architecture should really override this if possible, at least
+ * doing a check on the get_fs()
+ */
+#ifndef __access_ok
+static inline int __access_ok(unsigned long addr, unsigned long size)
+{
+ return 1;
+}
+#endif
+
+/*
+ * These are the main single-value transfer routines. They automatically
+ * use the right size if we just have the right pointer type.
+ * This version just falls back to copy_{from,to}_user, which should
+ * provide a fast-path for small values.
+ */
+#define __put_user(x, ptr) \
+({ \
+ __typeof__(*(ptr)) __x = (x); \
+ int __pu_err = -EFAULT; \
+ __chk_user_ptr(ptr); \
+ switch (sizeof (*(ptr))) { \
+ case 1: \
+ case 2: \
+ case 4: \
+ case 8: \
+ __pu_err = __put_user_fn(sizeof (*(ptr)), \
+ ptr, &__x); \
+ break; \
+ default: \
+ __put_user_bad(); \
+ break; \
+ } \
+ __pu_err; \
+})
+
+#define put_user(x, ptr) \
+({ \
+ void __user *__p = (ptr); \
+ might_fault(); \
+ access_ok(__p, sizeof(*ptr)) ? \
+ __put_user((x), ((__typeof__(*(ptr)) __user *)__p)) : \
+ -EFAULT; \
+})
+
+#ifndef __put_user_fn
+
+static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
+{
+ return unlikely(raw_copy_to_user(ptr, x, size)) ? -EFAULT : 0;
+}
+
+#define __put_user_fn(sz, u, k) __put_user_fn(sz, u, k)
+
+#endif
+
+extern int __put_user_bad(void) __attribute__((noreturn));
+
+#define __get_user(x, ptr) \
+({ \
+ int __gu_err = -EFAULT; \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: { \
+ unsigned char __x = 0; \
+ __gu_err = __get_user_fn(sizeof (*(ptr)), \
+ ptr, &__x); \
+ (x) = *(__force __typeof__(*(ptr)) *) &__x; \
+ break; \
+ }; \
+ case 2: { \
+ unsigned short __x = 0; \
+ __gu_err = __get_user_fn(sizeof (*(ptr)), \
+ ptr, &__x); \
+ (x) = *(__force __typeof__(*(ptr)) *) &__x; \
+ break; \
+ }; \
+ case 4: { \
+ unsigned int __x = 0; \
+ __gu_err = __get_user_fn(sizeof (*(ptr)), \
+ ptr, &__x); \
+ (x) = *(__force __typeof__(*(ptr)) *) &__x; \
+ break; \
+ }; \
+ case 8: { \
+ unsigned long long __x = 0; \
+ __gu_err = __get_user_fn(sizeof (*(ptr)), \
+ ptr, &__x); \
+ (x) = *(__force __typeof__(*(ptr)) *) &__x; \
+ break; \
+ }; \
+ default: \
+ __get_user_bad(); \
+ break; \
+ } \
+ __gu_err; \
+})
+
+#define get_user(x, ptr) \
+({ \
+ const void __user *__p = (ptr); \
+ might_fault(); \
+ access_ok(__p, sizeof(*ptr)) ? \
+ __get_user((x), (__typeof__(*(ptr)) __user *)__p) :\
+ ((x) = (__typeof__(*(ptr)))0,-EFAULT); \
+})
+
+#ifndef __get_user_fn
+static inline int __get_user_fn(size_t size, const void __user *ptr, void *x)
+{
+ return unlikely(raw_copy_from_user(x, ptr, size)) ? -EFAULT : 0;
+}
+
+#define __get_user_fn(sz, u, k) __get_user_fn(sz, u, k)
+
+#endif
+
+extern int __get_user_bad(void) __attribute__((noreturn));
+
+/*
+ * Copy a null terminated string from userspace.
+ */
+#ifndef __strncpy_from_user
+static inline long
+__strncpy_from_user(char *dst, const char __user *src, long count)
+{
+ char *tmp;
+ strncpy(dst, (const char __force *)src, count);
+ for (tmp = dst; *tmp && count > 0; tmp++, count--)
+ ;
+ return (tmp - dst);
+}
+#endif
+
+static inline long
+strncpy_from_user(char *dst, const char __user *src, long count)
+{
+ if (!access_ok(src, 1))
+ return -EFAULT;
+ return __strncpy_from_user(dst, src, count);
+}
+
+/*
+ * Return the size of a string (including the ending 0)
+ *
+ * Return 0 on exception, a value greater than N if too long
+ */
+#ifndef __strnlen_user
+#define __strnlen_user(s, n) (strnlen((s), (n)) + 1)
+#endif
+
+/*
+ * Unlike strnlen, strnlen_user includes the nul terminator in
+ * its returned count. Callers should check for a returned value
+ * greater than N as an indication the string is too long.
+ */
+static inline long strnlen_user(const char __user *src, long n)
+{
+ if (!access_ok(src, 1))
+ return 0;
+ return __strnlen_user(src, n);
+}
+
+/*
+ * Zero Userspace
+ */
+#ifndef __clear_user
+static inline __must_check unsigned long
+__clear_user(void __user *to, unsigned long n)
+{
+ memset((void __force *)to, 0, n);
+ return 0;
+}
+#endif
+
+static inline __must_check unsigned long
+clear_user(void __user *to, unsigned long n)
+{
+ might_fault();
+ if (!access_ok(to, n))
+ return n;
+
+ return __clear_user(to, n);
+}
+
+#include <asm/extable.h>
+
+#endif /* __ASM_GENERIC_UACCESS_H */