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>

diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
index 91a45514488e9135a2633bf322ce8a7dc5d6fc08..78fd8014d9014340b5755d315b1e6f701308f440 100644 (file)
--- a/lib/efi_loader/efi_runtime.c
+++ b/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

diff --git a/lib/efi_loader/efi_var_mem.c b/lib/efi_loader/efi_var_mem.c
index 856e5e1d56faa9d96241ba3588241de14ebd75f1..bfa8a56a8f63ec9fae00ad59889bcf252ec0ac9a 100644 (file)
--- a/lib/efi_loader/efi_var_mem.c
+++ b/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));