From 02748d0a584f22a568347d719291725e6fd63029 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Tue, 13 Oct 2020 19:08:25 +0100 Subject: [PATCH] [efi] Defer local download process until file has been opened When iPXE is downloading a file from an EFI_FILE_PROTOCOL instance backed by an EFI_BLOCK_IO_PROTOCOL instance provided by the same iPXE binary (e.g. via a hooked SAN device), then it is possible for step() to be invoked as a result of the calls into the EFI_BLOCK_IO_PROTOCOL methods. This can potentially result in efi_local_step() being run prematurely, before the file has been opened and before the parent interface has been attached. Fix by deferring starting the download process until immediately prior to returning from efi_local_open(). Signed-off-by: Michael Brown --- src/interface/efi/efi_local.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/interface/efi/efi_local.c b/src/interface/efi/efi_local.c index 79ea822f3..617895650 100644 --- a/src/interface/efi/efi_local.c +++ b/src/interface/efi/efi_local.c @@ -548,8 +548,8 @@ static int efi_local_open ( struct interface *xfer, struct uri *uri ) { } ref_init ( &local->refcnt, NULL ); intf_init ( &local->xfer, &efi_local_xfer_desc, &local->refcnt ); - process_init ( &local->process, &efi_local_process_desc, - &local->refcnt ); + process_init_stopped ( &local->process, &efi_local_process_desc, + &local->refcnt ); /* Open specified volume */ if ( ( rc = efi_local_open_volume ( local, volume ) ) != 0 ) @@ -563,6 +563,9 @@ static int efi_local_open ( struct interface *xfer, struct uri *uri ) { if ( ( rc = efi_local_len ( local ) ) != 0 ) goto err_len; + /* Start download process */ + process_add ( &local->process ); + /* Attach to parent interface, mortalise self, and return */ intf_plug_plug ( &local->xfer, xfer ); ref_put ( &local->refcnt );