Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967532AbdCXUZx (ORCPT ); Fri, 24 Mar 2017 16:25:53 -0400 Received: from mail-qt0-f196.google.com ([209.85.216.196]:35538 "EHLO mail-qt0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755897AbdCXUZn (ORCPT ); Fri, 24 Mar 2017 16:25:43 -0400 MIME-Version: 1.0 In-Reply-To: <47e87c8eccc0ee5c4033ece037c0bffc32782876.1490376860.git.jan.kiszka@siemens.com> References: <47e87c8eccc0ee5c4033ece037c0bffc32782876.1490376860.git.jan.kiszka@siemens.com> From: Andy Shevchenko Date: Fri, 24 Mar 2017 22:25:41 +0200 Message-ID: Subject: Re: [PATCH v2 5/7] efi/capsule: Prepare for loading images with security header To: Jan Kiszka Cc: Matt Fleming , Ard Biesheuvel , linux-efi@vger.kernel.org, Linux Kernel Mailing List , "Bryan O'Donoghue" , Hock Leong Kweh , Borislav Petkov , Sascha Weisenberger Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5967 Lines: 145 On Fri, Mar 24, 2017 at 7:34 PM, Jan Kiszka wrote: > The Quark security header is nicely located in front of the capsule > image, but we still need to pass the image to the update service as if > there was none. Prepare efi_capsule_update and its user for this by > defining and evaluating a EFI header displacement in the image located > in memory. For standard-conforming capsules, this displacement is 0. To me sounds like new field should be of type size_t. > > Signed-off-by: Jan Kiszka > --- > drivers/firmware/efi/capsule-loader.c | 19 +++++++++++++------ > drivers/firmware/efi/capsule.c | 21 +++++++++++++++++---- > include/linux/efi.h | 1 + > 3 files changed, 31 insertions(+), 10 deletions(-) > > diff --git a/drivers/firmware/efi/capsule-loader.c b/drivers/firmware/efi/capsule-loader.c > index 37d3f6e..59e2694 100644 > --- a/drivers/firmware/efi/capsule-loader.c > +++ b/drivers/firmware/efi/capsule-loader.c > @@ -26,6 +26,7 @@ struct capsule_info { > long index; > size_t count; > size_t total_size; > + unsigned int efi_hdr_displacement; > struct page **pages; > size_t page_bytes_remain; > }; > @@ -83,6 +84,8 @@ static int efi_capsule_setup_info(struct capsule_info *cap_info, > return ret; > } > > + cap_info->efi_hdr_displacement = 0; > + > cap_info->total_size = cap_hdr->imagesize; > temp_page = krealloc(cap_info->pages, > pages_needed * sizeof(void *), > @@ -103,16 +106,20 @@ static int efi_capsule_setup_info(struct capsule_info *cap_info, > **/ > static ssize_t efi_capsule_submit_update(struct capsule_info *cap_info) > { > + efi_capsule_header_t *cap_hdr; > + void *mapped_pages; > int ret; > - void *cap_hdr_temp; > > - cap_hdr_temp = vmap(cap_info->pages, cap_info->index, > - VM_MAP, PAGE_KERNEL); > - if (!cap_hdr_temp) > + mapped_pages = vmap(cap_info->pages, cap_info->index, > + VM_MAP, PAGE_KERNEL); > + if (!mapped_pages) > return -ENOMEM; > > - ret = efi_capsule_update(cap_hdr_temp, cap_info->pages); > - vunmap(cap_hdr_temp); > + cap_hdr = mapped_pages + cap_info->efi_hdr_displacement; > + > + ret = efi_capsule_update(cap_hdr, cap_info->efi_hdr_displacement, > + cap_info->pages); > + vunmap(mapped_pages); > if (ret) { > pr_err("capsule update failed\n"); > return ret; > diff --git a/drivers/firmware/efi/capsule.c b/drivers/firmware/efi/capsule.c > index 6eedff4..a60c4c4 100644 > --- a/drivers/firmware/efi/capsule.c > +++ b/drivers/firmware/efi/capsule.c > @@ -184,6 +184,8 @@ efi_capsule_update_locked(efi_capsule_header_t *capsule, > /** > * efi_capsule_update - send a capsule to the firmware > * @capsule: capsule to send to firmware > + * @efi_hdr_displacement: EFI header offset on first data page (only needed for > + * non-conforming CSH capsules) > * @pages: an array of capsule data pages > * > * Build a scatter gather list with EFI capsule block descriptors to > @@ -214,9 +216,12 @@ efi_capsule_update_locked(efi_capsule_header_t *capsule, > * > * Return 0 on success, a converted EFI status code on failure. > */ > -int efi_capsule_update(efi_capsule_header_t *capsule, struct page **pages) > +int efi_capsule_update(efi_capsule_header_t *capsule, > + unsigned int efi_hdr_displacement, > + struct page **pages) > { > u32 imagesize = capsule->imagesize; > + u32 total_size = imagesize + efi_hdr_displacement; > efi_guid_t guid = capsule->guid; > unsigned int count, sg_count; > u32 flags = capsule->flags; > @@ -224,11 +229,14 @@ int efi_capsule_update(efi_capsule_header_t *capsule, struct page **pages) > int rv, reset_type; > int i, j; > > - rv = efi_capsule_supported(guid, flags, imagesize, &reset_type); > + if (efi_hdr_displacement > PAGE_SIZE - sizeof(efi_capsule_header_t)) > + return -EINVAL; > + > + rv = efi_capsule_supported(guid, flags, total_size, &reset_type); > if (rv) > return rv; > > - count = DIV_ROUND_UP(imagesize, PAGE_SIZE); > + count = DIV_ROUND_UP(total_size, PAGE_SIZE); > sg_count = sg_pages_num(count); > > sg_pages = kzalloc(sg_count * sizeof(*sg_pages), GFP_KERNEL); > @@ -255,8 +263,13 @@ int efi_capsule_update(efi_capsule_header_t *capsule, struct page **pages) > for (j = 0; j < SGLIST_PER_PAGE && count > 0; j++) { > u64 sz = min_t(u64, imagesize, PAGE_SIZE); > > - sglist[j].length = sz; > sglist[j].data = page_to_phys(*pages++); > + if (efi_hdr_displacement > 0) { > + sglist[j].data += efi_hdr_displacement; > + sz -= efi_hdr_displacement; > + efi_hdr_displacement = 0; > + } > + sglist[j].length = sz; > > imagesize -= sz; > count--; > diff --git a/include/linux/efi.h b/include/linux/efi.h > index 94d34e0..d83095c6 100644 > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -1403,6 +1403,7 @@ extern int efi_capsule_supported(efi_guid_t guid, u32 flags, > size_t size, int *reset); > > extern int efi_capsule_update(efi_capsule_header_t *capsule, > + unsigned int efi_hdr_displacement, > struct page **pages); > > #ifdef CONFIG_EFI_RUNTIME_MAP > -- > 2.10.2 > -- With Best Regards, Andy Shevchenko