Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 3855543..c7c6e8b 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -2,14 +2,54 @@
 #ifndef __LINUX_UACCESS_H__
 #define __LINUX_UACCESS_H__
 
+#include <linux/fault-inject-usercopy.h>
+#include <linux/instrumented.h>
+#include <linux/minmax.h>
 #include <linux/sched.h>
 #include <linux/thread_info.h>
-#include <linux/kasan-checks.h>
-
-#define uaccess_kernel() segment_eq(get_fs(), KERNEL_DS)
 
 #include <asm/uaccess.h>
 
+#ifdef CONFIG_SET_FS
+/*
+ * Force the uaccess routines to be wired up for actual userspace access,
+ * overriding any possible set_fs(KERNEL_DS) still lingering around.  Undone
+ * using force_uaccess_end below.
+ */
+static inline mm_segment_t force_uaccess_begin(void)
+{
+	mm_segment_t fs = get_fs();
+
+	set_fs(USER_DS);
+	return fs;
+}
+
+static inline void force_uaccess_end(mm_segment_t oldfs)
+{
+	set_fs(oldfs);
+}
+#else /* CONFIG_SET_FS */
+typedef struct {
+	/* empty dummy */
+} mm_segment_t;
+
+#ifndef TASK_SIZE_MAX
+#define TASK_SIZE_MAX			TASK_SIZE
+#endif
+
+#define uaccess_kernel()		(false)
+#define user_addr_max()			(TASK_SIZE_MAX)
+
+static inline mm_segment_t force_uaccess_begin(void)
+{
+	return (mm_segment_t) { };
+}
+
+static inline void force_uaccess_end(mm_segment_t oldfs)
+{
+}
+#endif /* CONFIG_SET_FS */
+
 /*
  * Architectures should provide two primitives (raw_copy_{to,from}_user())
  * and get rid of their private instances of copy_{to,from}_user() and
@@ -58,7 +98,7 @@
 static __always_inline __must_check unsigned long
 __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
 {
-	kasan_check_write(to, n);
+	instrument_copy_from_user(to, from, n);
 	check_object_size(to, n, false);
 	return raw_copy_from_user(to, from, n);
 }
@@ -67,7 +107,9 @@
 __copy_from_user(void *to, const void __user *from, unsigned long n)
 {
 	might_fault();
-	kasan_check_write(to, n);
+	if (should_fail_usercopy())
+		return n;
+	instrument_copy_from_user(to, from, n);
 	check_object_size(to, n, false);
 	return raw_copy_from_user(to, from, n);
 }
@@ -88,7 +130,9 @@
 static __always_inline __must_check unsigned long
 __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
 {
-	kasan_check_read(from, n);
+	if (should_fail_usercopy())
+		return n;
+	instrument_copy_to_user(to, from, n);
 	check_object_size(from, n, true);
 	return raw_copy_to_user(to, from, n);
 }
@@ -97,7 +141,9 @@
 __copy_to_user(void __user *to, const void *from, unsigned long n)
 {
 	might_fault();
-	kasan_check_read(from, n);
+	if (should_fail_usercopy())
+		return n;
+	instrument_copy_to_user(to, from, n);
 	check_object_size(from, n, true);
 	return raw_copy_to_user(to, from, n);
 }
@@ -108,8 +154,8 @@
 {
 	unsigned long res = n;
 	might_fault();
-	if (likely(access_ok(from, n))) {
-		kasan_check_write(to, n);
+	if (!should_fail_usercopy() && likely(access_ok(from, n))) {
+		instrument_copy_from_user(to, from, n);
 		res = raw_copy_from_user(to, from, n);
 	}
 	if (unlikely(res))
@@ -126,8 +172,10 @@
 _copy_to_user(void __user *to, const void *from, unsigned long n)
 {
 	might_fault();
+	if (should_fail_usercopy())
+		return n;
 	if (access_ok(to, n)) {
-		kasan_check_read(from, n);
+		instrument_copy_to_user(to, from, n);
 		n = raw_copy_to_user(to, from, n);
 	}
 	return n;
@@ -163,6 +211,19 @@
 }
 #endif
 
+#ifndef copy_mc_to_kernel
+/*
+ * Without arch opt-in this generic copy_mc_to_kernel() will not handle
+ * #MC (or arch equivalent) during source read.
+ */
+static inline unsigned long __must_check
+copy_mc_to_kernel(void *dst, const void *src, size_t cnt)
+{
+	memcpy(dst, src, cnt);
+	return 0;
+}
+#endif
+
 static __always_inline void pagefault_disabled_inc(void)
 {
 	current->pagefault_disabled++;
@@ -301,68 +362,33 @@
 	return 0;
 }
 
-/*
- * probe_kernel_read(): safely attempt to read from a location
- * @dst: pointer to the buffer that shall take the data
- * @src: address to read from
- * @size: size of the data chunk
- *
- * Safely read from address @src to the buffer at @dst.  If a kernel fault
- * happens, handle that and return -EFAULT.
- */
-extern long probe_kernel_read(void *dst, const void *src, size_t size);
-extern long __probe_kernel_read(void *dst, const void *src, size_t size);
+bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size);
 
-/*
- * probe_user_read(): safely attempt to read from a location in user space
- * @dst: pointer to the buffer that shall take the data
- * @src: address to read from
- * @size: size of the data chunk
- *
- * Safely read from address @src to the buffer at @dst.  If a kernel fault
- * happens, handle that and return -EFAULT.
- */
-extern long probe_user_read(void *dst, const void __user *src, size_t size);
-extern long __probe_user_read(void *dst, const void __user *src, size_t size);
+long copy_from_kernel_nofault(void *dst, const void *src, size_t size);
+long notrace copy_to_kernel_nofault(void *dst, const void *src, size_t size);
 
-/*
- * probe_kernel_write(): safely attempt to write to a location
- * @dst: address to write to
- * @src: pointer to the data that shall be written
- * @size: size of the data chunk
- *
- * Safely write to address @dst from the buffer at @src.  If a kernel fault
- * happens, handle that and return -EFAULT.
- */
-extern long notrace probe_kernel_write(void *dst, const void *src, size_t size);
-extern long notrace __probe_kernel_write(void *dst, const void *src, size_t size);
+long copy_from_user_nofault(void *dst, const void __user *src, size_t size);
+long notrace copy_to_user_nofault(void __user *dst, const void *src,
+		size_t size);
 
-/*
- * probe_user_write(): safely attempt to write to a location in user space
- * @dst: address to write to
- * @src: pointer to the data that shall be written
- * @size: size of the data chunk
- *
- * Safely write to address @dst from the buffer at @src.  If a kernel fault
- * happens, handle that and return -EFAULT.
- */
-extern long notrace probe_user_write(void __user *dst, const void *src, size_t size);
-extern long notrace __probe_user_write(void __user *dst, const void *src, size_t size);
+long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr,
+		long count);
 
-extern long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count);
-extern long strncpy_from_unsafe_user(char *dst, const void __user *unsafe_addr,
-				     long count);
-extern long strnlen_unsafe_user(const void __user *unsafe_addr, long count);
+long strncpy_from_user_nofault(char *dst, const void __user *unsafe_addr,
+		long count);
+long strnlen_user_nofault(const void __user *unsafe_addr, long count);
 
 /**
- * probe_kernel_address(): safely attempt to read from a location
- * @addr: address to read from
- * @retval: read into this variable
+ * get_kernel_nofault(): safely attempt to read from a location
+ * @val: read into this variable
+ * @ptr: address to read from
  *
  * Returns 0 on success, or -EFAULT.
  */
-#define probe_kernel_address(addr, retval)		\
-	probe_kernel_read(&retval, addr, sizeof(retval))
+#define get_kernel_nofault(val, ptr) ({				\
+	const typeof(val) *__gk_ptr = (ptr);			\
+	copy_from_kernel_nofault(&(val), __gk_ptr, sizeof(val));\
+})
 
 #ifndef user_access_begin
 #define user_access_begin(ptr,len) access_ok(ptr, len)
@@ -374,6 +400,14 @@
 static inline unsigned long user_access_save(void) { return 0UL; }
 static inline void user_access_restore(unsigned long flags) { }
 #endif
+#ifndef user_write_access_begin
+#define user_write_access_begin user_access_begin
+#define user_write_access_end user_access_end
+#endif
+#ifndef user_read_access_begin
+#define user_read_access_begin user_access_begin
+#define user_read_access_end user_access_end
+#endif
 
 #ifdef CONFIG_HARDENED_USERCOPY
 void usercopy_warn(const char *name, const char *detail, bool to_user,