UPSTREAM: maccess: rename strncpy_from_unsafe_strict to strncpy_from_kernel_nofault

This matches the naming of strncpy_from_user_nofault, and also makes it
more clear what the function is supposed to do.

Change-Id: I862c2c72cbc36c67e35434dc29cfc00fee3abd14
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-8-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/mm/maccess.c

@@ -34,7 +34,7 @@ long probe_kernel_read_strict(void *dst, const void *src, size_t size)
 	return __probe_kernel_read(dst, src, size);
 }
 
-long strncpy_from_unsafe_strict(char *dst, const void *unsafe_addr, long count)
+long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
 {
 	if (unlikely(invalid_probe_range((unsigned long)unsafe_addr)))
 		return -EFAULT;

include/linux/uaccess.h

@@ -355,8 +355,8 @@ extern long notrace probe_user_write(void __user *dst, const void *src, size_t s
 extern long notrace __probe_user_write(void __user *dst, const void *src, size_t size);
 
 extern long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count);
-extern long strncpy_from_unsafe_strict(char *dst, const void *unsafe_addr,
-				       long count);
+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);
 long strncpy_from_user_nofault(char *dst, const void __user *unsafe_addr,
 		long count);

kernel/trace/bpf_trace.c

@@ -250,7 +250,7 @@ bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr,
 	 * is returned that can be used for bpf_perf_event_output() et al.
 	 */
 	ret = compat ? strncpy_from_unsafe(dst, unsafe_ptr, size) :
-	      strncpy_from_unsafe_strict(dst, unsafe_ptr, size);
+	      strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
 	if (unlikely(ret < 0))
 out:
 		memset(dst, 0, size);
@@ -425,7 +425,7 @@ fmt_str:
 				break;
 #endif
 			case 'k':
-				strncpy_from_unsafe_strict(buf, unsafe_ptr,
+				strncpy_from_kernel_nofault(buf, unsafe_ptr,
 							   sizeof(buf));
 				break;
 			case 'u':

mm/maccess.c

@@ -174,7 +174,7 @@ EXPORT_SYMBOL_GPL(probe_user_write);
  * If @count is smaller than the length of the string, copies @count-1 bytes,
  * sets the last byte of @dst buffer to NUL and returns @count.
  *
- * Same as strncpy_from_unsafe_strict() except that for architectures with
+ * Same as strncpy_from_kernel_nofault() except that for architectures with
  * not fully separated user and kernel address spaces this function also works
  * for user address tanges.
  *
@@ -186,7 +186,7 @@ long __weak strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
     __attribute__((alias("__strncpy_from_unsafe")));
 
 /**
- * strncpy_from_unsafe_strict: - Copy a NUL terminated string from unsafe
+ * strncpy_from_kernel_nofault: - Copy a NUL terminated string from unsafe
  *				 address.
  * @dst:   Destination address, in kernel space.  This buffer must be at
  *         least @count bytes long.
@@ -203,7 +203,7 @@ long __weak strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
  * If @count is smaller than the length of the string, copies @count-1 bytes,
  * sets the last byte of @dst buffer to NUL and returns @count.
  */
-long __weak strncpy_from_unsafe_strict(char *dst, const void *unsafe_addr,
+long __weak strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr,
 				       long count)
     __attribute__((alias("__strncpy_from_unsafe")));