Re: [PATCH v3 1/3] dm: Add verity helpers for LoadPin
From: Matthias Kaehlcke <mka@chromium.org>
Date: 2022-05-12 20:45:05
Also in:
dm-devel, linux-raid, lkml
On Thu, May 12, 2022 at 01:19:12PM -0400, Mike Snitzer wrote:
On Wed, May 11 2022 at 4:54P -0400, Matthias Kaehlcke [off-list ref] wrote:quoted
Alasdar/Mike, I'd be interested in your take on adding these functions to verity/DM, to get an idea whether this series has a path forward to landing upstream.I'll be reviewing your patchset now. Comments inlined below.quoted
On Wed, May 04, 2022 at 12:54:17PM -0700, Matthias Kaehlcke wrote:quoted
LoadPin limits loading of kernel modules, firmware and certain other files to a 'pinned' file system (typically a read-only rootfs). To provide more flexibility LoadPin is being extended to also allow loading these files from trusted dm-verity devices. For that purpose LoadPin can be provided with a list of verity root digests that it should consider as trusted. Add a bunch of helpers to allow LoadPin to check whether a DM device is a trusted verity device. The new functions broadly fall in two categories: those that need access to verity internals (like the root digest), and the 'glue' between LoadPin and verity. The new file dm-verity-loadpin.c contains the glue functions. Signed-off-by: Matthias Kaehlcke <mka@chromium.org> --- Changes in v3: - none Changes in v2: - none drivers/md/Makefile | 6 +++ drivers/md/dm-verity-loadpin.c | 80 +++++++++++++++++++++++++++++++ drivers/md/dm-verity-target.c | 33 +++++++++++++ drivers/md/dm-verity.h | 4 ++ include/linux/dm-verity-loadpin.h | 27 +++++++++++ 5 files changed, 150 insertions(+) create mode 100644 drivers/md/dm-verity-loadpin.c create mode 100644 include/linux/dm-verity-loadpin.hdiff --git a/drivers/md/Makefile b/drivers/md/Makefile index 0454b0885b01..e12cd004d375 100644 --- a/drivers/md/Makefile +++ b/drivers/md/Makefile@@ -100,6 +100,12 @@ ifeq ($(CONFIG_IMA),y) dm-mod-objs += dm-ima.o endif +ifeq ($(CONFIG_DM_VERITY),y) +ifeq ($(CONFIG_SECURITY_LOADPIN),y) +dm-mod-objs += dm-verity-loadpin.o +endif +endif +Why are you extending dm-mod-objs? Why not dm-verity-objs?
Sorry, I missed to address this comment in my earlier reply. I don't recall why I chose dm-mod-objs initially, agreed that dm-verity-objs seems a better fit.