If an application or driver started via StartImage returns without calling Exit, StartImage has to call Exit. This is mandated by the UEFI spec and we do the same in efi_do_enter().
The patch looks bigger than it is. To avoid a forward declaration function efi_exit() was moved up. Only one (void*) was replaced by (void *). The only real change is in efi_start_image().
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- Without this patch on Ubuntu 16.04 a crash could be observed in efi_selftest_startimage_return.c. With the patch it is gone. But this could be coincidence. --- lib/efi_loader/efi_boottime.c | 99 ++++++++++++++++++++++--------------------- 1 file changed, 51 insertions(+), 48 deletions(-)
diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c index 0ac5b44..62a24bf 100644 --- a/lib/efi_loader/efi_boottime.c +++ b/lib/efi_loader/efi_boottime.c @@ -1519,6 +1519,54 @@ failure: }
/* + * Leave an EFI application or driver. + * + * This function implements the Exit service. + * See the Unified Extensible Firmware Interface (UEFI) specification + * for details. + * + * @image_handle handle of the application or driver that is exiting + * @exit_status status code + * @exit_data_size size of the buffer in bytes + * @exit_data buffer with data describing an error + * @return status code + */ +static efi_status_t EFIAPI efi_exit(efi_handle_t image_handle, + efi_status_t exit_status, unsigned long exit_data_size, + int16_t *exit_data) +{ + /* + * We require that the handle points to the original loaded + * image protocol interface. + * + * For getting the longjmp address this is safer than locating + * the protocol because the protocol may have been reinstalled + * pointing to another memory location. + * + * TODO: We should call the unload procedure of the loaded + * image protocol. + */ + struct efi_loaded_image *loaded_image_info = (void *)image_handle; + + EFI_ENTRY("%p, %ld, %ld, %p", image_handle, exit_status, + exit_data_size, exit_data); + + /* Make sure entry/exit counts for EFI world cross-overs match */ + EFI_EXIT(exit_status); + + /* + * But longjmp out with the U-Boot gd, not the application's, as + * the other end is a setjmp call inside EFI context. + */ + efi_restore_gd(); + + loaded_image_info->exit_status = exit_status; + longjmp(&loaded_image_info->exit_jmp, 1); + + panic("EFI application exited"); +} + +/* * Call the entry point of an image. * * This function implements the StartImage service. @@ -1575,59 +1623,14 @@ static efi_status_t EFIAPI efi_start_image(efi_handle_t image_handle,
ret = EFI_CALL(entry(image_handle, &systab));
+ /* Clean up the image */ + ret = EFI_CALL(efi_exit(image_handle, ret, 0, NULL)); + /* Should usually never get here */ return EFI_EXIT(ret); }
/* - * Leave an EFI application or driver. - * - * This function implements the Exit service. - * See the Unified Extensible Firmware Interface (UEFI) specification - * for details. - * - * @image_handle handle of the application or driver that is exiting - * @exit_status status code - * @exit_data_size size of the buffer in bytes - * @exit_data buffer with data describing an error - * @return status code - */ -static efi_status_t EFIAPI efi_exit(efi_handle_t image_handle, - efi_status_t exit_status, unsigned long exit_data_size, - int16_t *exit_data) -{ - /* - * We require that the handle points to the original loaded - * image protocol interface. - * - * For getting the longjmp address this is safer than locating - * the protocol because the protocol may have been reinstalled - * pointing to another memory location. - * - * TODO: We should call the unload procedure of the loaded - * image protocol. - */ - struct efi_loaded_image *loaded_image_info = (void*)image_handle; - - EFI_ENTRY("%p, %ld, %ld, %p", image_handle, exit_status, - exit_data_size, exit_data); - - /* Make sure entry/exit counts for EFI world cross-overs match */ - EFI_EXIT(exit_status); - - /* - * But longjmp out with the U-Boot gd, not the application's, as - * the other end is a setjmp call inside EFI context. - */ - efi_restore_gd(); - - loaded_image_info->exit_status = exit_status; - longjmp(&loaded_image_info->exit_jmp, 1); - - panic("EFI application exited"); -} - -/* * Unload an EFI image. * * This function implements the UnloadImage service.