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efi_loader: don't use memmove() in efi_var_mem_del()

efi_var_mem_del() is in __efi_runtime because it would be needed for a
runtime implementation of SetVariable(). memmove() is not in __efi_runtime.
So we should not use it in efi_var_mem_del().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Heinrich Schuchardt пре 3 година
родитељ
комит
ebbad02c1b
2 измењених фајлова са 4 додато и 1 уклоњено
  1. 2 0
      lib/efi_loader/efi_runtime.c
  2. 2 1
      lib/efi_loader/efi_var_mem.c

+ 2 - 0
lib/efi_loader/efi_runtime.c

@@ -144,6 +144,8 @@ efi_status_t efi_init_runtime_supported(void)
  *
  * At runtime memcpy() is not available.
  *
+ * Overlapping memory areas can be copied safely if src >= dest.
+ *
  * @dest:	destination buffer
  * @src:	source buffer
  * @n:		number of bytes to copy

+ 2 - 1
lib/efi_loader/efi_var_mem.c

@@ -120,7 +120,8 @@ void __efi_runtime efi_var_mem_del(struct efi_var_entry *var)
 	       ALIGN((uintptr_t)data + var->length, 8);
 	efi_var_buf->length -= (uintptr_t)next - (uintptr_t)var;
 
-	memmove(var, next, (uintptr_t)last - (uintptr_t)next);
+	/* efi_memcpy_runtime() can be used because next >= var. */
+	efi_memcpy_runtime(var, next, (uintptr_t)last - (uintptr_t)next);
 	efi_var_buf->crc32 = crc32(0, (u8 *)efi_var_buf->var,
 				   efi_var_buf->length -
 				   sizeof(struct efi_var_file));