Commit Graph

10 Commits

Author SHA1 Message Date
Louis Collard 7a64c5597a tpm: Allow tpm_tis drivers to set hwrng quality.
Adds plumbing required for drivers based on tpm_tis to set hwrng quality.

Signed-off-by: Louis Collard <louiscollard@chromium.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-07-28 17:03:11 +03:00
Kees Cook 3c8ba0d61d kernel.h: Retain constant expression output for max()/min()
In the effort to remove all VLAs from the kernel[1], it is desirable to
build with -Wvla.  However, this warning is overly pessimistic, in that
it is only happy with stack array sizes that are declared as constant
expressions, and not constant values.  One case of this is the
evaluation of the max() macro which, due to its construction, ends up
converting constant expression arguments into a constant value result.

All attempts to rewrite this macro with __builtin_constant_p() failed
with older compilers (e.g.  gcc 4.4)[2].  However, Martin Uecker,
constructed[3] a mind-shattering solution that works everywhere.
Cthulhu fhtagn!

This patch updates the min()/max() macros to evaluate to a constant
expression when called on constant expression arguments.  This removes
several false-positive stack VLA warnings from an x86 allmodconfig build
when -Wvla is added:

  $ diff -u before.txt after.txt | grep ^-
  -drivers/input/touchscreen/cyttsp4_core.c:871:2: warning: ISO C90 forbids variable length array ‘ids’ [-Wvla]
  -fs/btrfs/tree-checker.c:344:4: warning: ISO C90 forbids variable length array ‘namebuf’ [-Wvla]
  -lib/vsprintf.c:747:2: warning: ISO C90 forbids variable length array ‘sym’ [-Wvla]
  -net/ipv4/proc.c:403:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla]
  -net/ipv6/proc.c:198:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla]
  -net/ipv6/proc.c:218:2: warning: ISO C90 forbids variable length array ‘buff64’ [-Wvla]

This also updates two cases where different enums were being compared
and explicitly casts them to int (which matches the old side-effect of
the single-evaluation code): one in tpm/tpm_tis_core.h, and one in
drm/drm_color_mgmt.c.

 [1] https://lkml.org/lkml/2018/3/7/621
 [2] https://lkml.org/lkml/2018/3/10/170
 [3] https://lkml.org/lkml/2018/3/20/845

Co-Developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Co-Developed-by: Martin Uecker <Martin.Uecker@med.uni-goettingen.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 14:17:16 -07:00
Javier Martinez Canillas 764325add6 tpm: delete the TPM_TIS_CLK_ENABLE flag
This flag is only used to warn if CLKRUN_EN wasn't disabled on Braswell
systems, but the only way this can happen is if the code is not correct.

So it's an unnecessary check that just makes the code harder to read.

Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-01-08 12:58:38 +02:00
Azhar Shaikh b3e958ce4c tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd()
Commit 5e572cab92 ("tpm: Enable CLKRUN protocol for Braswell
systems") disabled CLKRUN protocol during TPM transactions and re-enabled
once the transaction is completed. But there were still some corner cases
observed where, reading of TPM header failed for savestate command
while going to suspend, which resulted in suspend failure.
To fix this issue keep the CLKRUN protocol disabled for the entire
duration of a single TPM command and not disabling and re-enabling
again for every TPM transaction. For the other TPM accesses outside
TPM command flow, add a higher level of disabling and re-enabling
the CLKRUN protocol, instead of doing for every TPM transaction.

Fixes: 5e572cab92 ("tpm: Enable CLKRUN protocol for Braswell systems")
Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
2018-01-08 12:58:38 +02:00
Azhar Shaikh c382babccb tpm_tis: Move ilb_base_addr to tpm_tis_data
Move static variable ilb_base_addr to tpm_tis_data.

Cc: stable@vger.kernel.org
Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
2018-01-08 12:58:37 +02:00
Arnd Bergmann c37fbc09bd tpm: constify transmit data pointers
Making cmd_getticks 'const' introduced a couple of harmless warnings:

drivers/char/tpm/tpm_tis_core.c: In function 'probe_itpm':
drivers/char/tpm/tpm_tis_core.c:469:31: error: passing argument 2 of 'tpm_tis_send_data' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  rc = tpm_tis_send_data(chip, cmd_getticks, len);
drivers/char/tpm/tpm_tis_core.c:477:31: error: passing argument 2 of 'tpm_tis_send_data' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  rc = tpm_tis_send_data(chip, cmd_getticks, len);
drivers/char/tpm/tpm_tis_core.c:255:12: note: expected 'u8 * {aka unsigned char *}' but argument is of type 'const u8 * {aka const unsigned char *}'
 static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)

This changes the related functions to all take 'const' pointers
so that gcc can see this as being correct. I had to slightly
modify the logic around tpm_tis_spi_transfer() for this to work
without introducing ugly casts.

Cc: stable@vger.kernel.org
Fixes: 5e35bd8e06b9 ("tpm_tis: make array cmd_getticks static const to shink object code size")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-10-18 18:28:45 +03:00
Maciej S. Szmigiero 1d70fe9d9c tpm_tis: use default timeout value if chip reports it as zero
Since commit 1107d065fd ("tpm_tis: Introduce intermediate layer for
TPM access") Atmel 3203 TPM on ThinkPad X61S (TPM firmware version 13.9)
no longer works.  The initialization proceeds fine until we get and
start using chip-reported timeouts - and the chip reports C and D
timeouts of zero.

It turns out that until commit 8e54caf407 ("tpm: Provide a generic
means to override the chip returned timeouts") we had actually let
default timeout values remain in this case, so let's bring back this
behavior to make chips like Atmel 3203 work again.

Use a common code that was introduced by that commit so a warning is
printed in this case and /sys/class/tpm/tpm*/timeouts correctly says the
timeouts aren't chip-original.

Fixes: 1107d065fd ("tpm_tis: Introduce intermediate layer for TPM access")
Cc: stable@vger.kernel.org
Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-01-23 18:28:18 +02:00
Christophe Ricard 41a5e1cf1f tpm/tpm_tis: Split tpm_tis driver into a core and TCG TIS compliant phy
To avoid code duplication between the old tpm_tis and the new and future
native tcg tis driver(ie: spi, i2c...), the tpm_tis driver was reworked,
so that all common logic is extracted and can be reused from all drivers.

The core methods can also be used from other TIS like drivers.

itpm workaround is now managed with a specific tis flag
TPM_TIS_ITPM_POSSIBLE.

This commit is based on the initial work by Peter Huewe.

Signed-off-by: Peter Huewe <peter.huewe@infineon.com>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-06-25 17:28:57 +03:00
Christophe Ricard 1107d065fd tpm_tis: Introduce intermediate layer for TPM access
This splits tpm_tis in a high-level protocol part and a low-level interface
for the actual TPM communication. The low-level interface can then be
implemented by additional drivers to provide access to TPMs using other
mechanisms, for example native I2C or SPI transfers, while still reusing
the same TIS protocol implementation.

Though the ioread/iowrite calls cannot fail, other implementations of this
interface might want to return error codes if their communication fails.

This follows the usual pattern of negative values representing errors and
zero representing success. Positive values are not used (yet).

Errors are passed back to the caller if possible. If the interface of a
function does not allow that, it tries to do the most sensible thing it
can, but this might also mean ignoring the error in this instance.

This commit is based on the initial work by Peter Huewe.

Signed-off-by: Alexander Steffen <Alexander.Steffen@infineon.com>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-06-25 17:26:35 +03:00
Christophe Ricard 57dacc2b4c tpm: tpm_tis: Share common data between phys
Split priv_data structure in common and phy specific structures. This will
allow in future patches to reuse the same tis logic on top of new phy such
as spi and i2c. Ultimately, other drivers may reuse this tis logic.
(e.g: st33zp24...)

iobase field is specific to TPM addressed on 0xFED4xxxx on LPC/SPI bus.

This commit is based on the initial work by Peter Huewe.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-06-25 17:26:35 +03:00