9 Commits

Author SHA1 Message Date
Jithu Joseph
4fb858f3dc platform/x86/intel/ifs: Add current_batch sysfs entry
Initial implementation assumed a single IFS test image file with a
fixed name ff-mm-ss.scan. (where ff, mm, ss refers to family, model and
stepping of the core).

Subsequently, it became evident that supporting more than one test
image file is needed to provide more comprehensive test coverage. (Test
coverage in this scenario refers to testing more transistors in the core
to identify faults).

The other alternative of increasing the size of a single scan test image
file would not work as the  upper bound is limited by the size of memory
area reserved by BIOS for loading IFS test image.

Introduce "current_batch" file which accepts a number. Writing a
number to the current_batch file would load the test image file by
name ff-mm-ss-<xy>.scan, where <xy> is the number written to the
"current_batch" file in hex. Range check of the input is done to verify
it not greater than 0xff.

For e.g if the scan test image comprises of 6 files, they would be named:

  06-8f-06-01.scan
  06-8f-06-02.scan
  06-8f-06-03.scan
  06-8f-06-04.scan
  06-8f-06-05.scan
  06-8f-06-06.scan

And writing 3 to current_batch would result in loading 06-8f-06-03.scan
above. The file can also be read to know the currently loaded file.

And testing a system looks like:

  for each scan file
  do
  	load the IFS test image file (write to the batch file)
  	for each core
  	do
  		test the core with this set of tests
  	done
  done

Qualify few error messages with the test image file suffix to provide
better context.

  [ bp: Massage commit message. Add link to the discussion. ]

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221107225323.2733518-13-jithu.joseph@intel.com
2022-11-19 11:29:00 +01:00
Jithu Joseph
48c6e7dc19 platform/x86/intel/ifs: Add metadata validation
The data portion of a IFS test image file contains a metadata region
containing possibly multiple metadata structures in addition to test
data and hashes.

    IFS Metadata layout
   +----------------------+  0
   |META_TYPE_IFS (=1)    |
   +----------------------+
   |meta_size             |
   +----------------------+
   |test type             |
   +----------------------+
   |fusa info             |
   +----------------------+
   |total images          |
   +----------------------+
   |current image#        |
   +----------------------+
   |total chunks          |
   +----------------------+
   |starting chunk        |
   +----------------------+
   |size per chunk        |
   +----------------------+
   |chunks per stride     |
   +----------------------+
   |Reserved[54]          |
   +----------------------+ 256
   |                      |
   |  Test Data/Chunks    |
   |                      |
   +----------------------+  meta_size
   |   META_TYPE_END (=0) |
   +----------------------+  meta_size + 4
   |   size of end (=8)   |
   +----------------------+  meta_size + 8

Introduce the layout of this meta_data structure and validate
the sanity of certain fields of the new image before loading.

Tweak references to IFS test image chunks to reflect the updated
layout of the test image.

  [ bp: Massage commit message. ]

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221117230408.30331-1-jithu.joseph@intel.com
2022-11-19 11:22:29 +01:00
Jithu Joseph
aa63e0fda8 platform/x86/intel/ifs: Use generic microcode headers and functions
Existing implementation (broken) of IFS used a header format (for IFS
test images) which was very similar to microcode format, but didn’t
accommodate extended signatures. This meant same IFS test image had to
be duplicated for different steppings and the validation code in the
driver was only looking at the primary header parameters. Going forward,
IFS test image headers have been tweaked to become fully compatible with
the microcode format.

Newer IFS test image headers will use header version 2 in order to
distinguish it from microcode images and older IFS test images.

In light of the above, reuse struct microcode_header_intel directly in
the IFS driver and reuse microcode functions for validation and sanity
checking.

  [ bp: Massage commit message. ]

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221117225039.30166-1-jithu.joseph@intel.com
2022-11-19 11:12:06 +01:00
Ashok Raj
8382fee3bb platform/x86/intel/ifs: Add metadata support
One of the existing reserved fields in the microcode header has been
allocated to indicate the size of metadata structures.

The location of metadata section within microcode header is as shown
below:

    Microcode Blob Format
   +----------------------+  Base
   |Header Version        |
   +----------------------+
   |Update revision       |
   +----------------------+
   |Date DDMMYYYY         |
   +----------------------+
   |Sig                   |
   +----------------------+
   |Checksum              |
   +----------------------+
   |Loader Version        |
   +----------------------+
   |Processor Flags       |
   +----------------------+
   |Data Size             |
   +----------------------+
   |Total Size            |
   +----------------------+
   |Meta Size             |
   +----------------------+
   |Reserved              |
   +----------------------+
   |Reserved              |
   +----------------------+  Base+48
   |                      |
   |    Microcode         |
   |     Data             |
   |                      |
   +----------------------+  Base+48+data_size-
   |                      |     meta_size
   |   Meta Data          |
   |   structure(s)       |
   |                      |
   +----------------------+  Base+48+data_size
   |                      |
   |   Extended Signature |
   |        Table         |
   |                      |
   +----------------------+  Base+total_size

Add an accessor function which will return a pointer to the start of a
specific meta_type being queried.

  [ bp: Massage commit message. ]

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221117035935.4136738-11-jithu.joseph@intel.com
2022-11-19 10:39:08 +01:00
Jithu Joseph
cb5eceee81 platform/x86/intel/ifs: Remove memory allocation from load path
IFS requires tests to be authenticated once for each CPU socket on a
system.

scan_chunks_sanity_check() was dynamically allocating memory to store
the state of whether tests have been authenticated on each socket for
every load operation.

Move the memory allocation to init path and store the pointer in
ifs_data struct.

Also rearrange the adjacent error checking in init for a more simplified
and natural flow.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221117195957.28225-1-jithu.joseph@intel.com
2022-11-18 21:43:18 +01:00
Jithu Joseph
f4e209e956 platform/x86/intel/ifs: Return a more appropriate error code
scan_chunks_sanity_check() returns -ENOMEM if it encounters an error
while copying IFS test image from memory to Secure Memory.

Return -EIO in this scenario, as it is more appropriate.

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20221117035935.4136738-3-jithu.joseph@intel.com
2022-11-18 21:30:36 +01:00
Jithu Joseph
684ec21570 platform/x86/intel/ifs: Authenticate and copy to secured memory
The IFS image contains hashes that will be used to authenticate the ifs
test chunks. First, use WRMSR to copy the hashes and enumerate the number
of test chunks, chunk size and the maximum number of cores that can run
scan test simultaneously.

Next, use WRMSR to authenticate each and every scan test chunk which is
stored in the IFS image. The CPU will check if the test chunks match
the hashes, otherwise failure is indicated to system software. If the test
chunk is authenticated, it is automatically copied to secured memory.

Use schedule_work_on() to perform the hash copy and authentication. Note
this needs only be done on the first logical cpu of each socket.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220506225410.1652287-8-tony.luck@intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-05-12 15:35:29 +02:00
Jithu Joseph
846e751ff3 platform/x86/intel/ifs: Check IFS Image sanity
IFS image is designed specifically for a given family, model and
stepping of the processor. Like Intel microcode header, the IFS image
has the Processor Signature, Checksum and Processor Flags that must be
matched with the information returned by the CPUID.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220506225410.1652287-7-tony.luck@intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-05-12 15:35:29 +02:00
Jithu Joseph
fb57fc785e platform/x86/intel/ifs: Read IFS firmware image
Driver probe routine allocates structure to communicate status
and parameters between functions in the driver. Also call
load_ifs_binary() to load the scan image file.

There is a separate scan image file for each processor family,
model, stepping combination. This is read from the static path:

  /lib/firmware/intel/ifs/{ff-mm-ss}.scan

Step 1 in loading is to generate the correct path and use
request_firmware_direct() to load into memory.

Subsequent patches will use the IFS MSR interfaces to copy
the image to BIOS reserved memory and validate the SHA256
checksums.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220506225410.1652287-6-tony.luck@intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-05-12 15:35:29 +02:00