From ebbad02c1b7140f7e9b479586d58aeca03f5350d Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Wed, 22 Jul 2020 07:56:14 +0200 Subject: [PATCH] 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 --- lib/efi_loader/efi_runtime.c | 2 ++ lib/efi_loader/efi_var_mem.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c index 91a4551..78fd801 100644 --- 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 856e5e1..bfa8a56 100644 --- 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)); -- 2.7.4