Commit Graph

6 Commits

Author SHA1 Message Date
Jarkko Sakkinen
58bac8cc30 tpm: replace TPM_TRANSMIT_RAW with TPM_TRANSMIT_NESTED
As TPM_TRANSMIT_RAW always requires also not to take locks for obvious
reasons (deadlock), this commit renames the flag as TPM_TRANSMIT_NESTED
and prevents taking tpm_mutex when the flag is given to tpm_transmit().

Suggested-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-07-28 17:03:11 +03:00
Tomas Winkler
627448e85c tpm: separate cmd_ready/go_idle from runtime_pm
Fix tpm ptt initialization error:
tpm tpm0: A TPM error (378) occurred get tpm pcr allocation.

We cannot use go_idle cmd_ready commands via runtime_pm handles
as with the introduction of localities this is no longer an optional
feature, while runtime pm can be not enabled.
Though cmd_ready/go_idle provides a power saving, it's also a part of
TPM2 protocol and should be called explicitly.
This patch exposes cmd_read/go_idle via tpm class ops and removes
runtime pm support as it is not used by any driver.

When calling from nested context always use both flags:
TPM_TRANSMIT_UNLOCKED and TPM_TRANSMIT_RAW. Both are needed to resolve
tpm spaces and locality request recursive calls to tpm_transmit().
TPM_TRANSMIT_RAW should never be used standalone as it will fail
on double locking. While TPM_TRANSMIT_UNLOCKED standalone should be
called from non-recursive locked contexts.

New wrappers are added tpm_cmd_ready() and tpm_go_idle() to
streamline tpm_try_transmit code.

tpm_crb no longer needs own power saving functions and can drop using
tpm_pm_suspend/resume.

This patch cannot be really separated from the locality fix.
Fixes: 888d867df4 (tpm: cmd_ready command can be issued only after granting locality)

Cc: stable@vger.kernel.org
Fixes: 888d867df4 (tpm: cmd_ready command can be issued only after granting locality)
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
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
Tadeusz Struk
8c81c24758 tpm: fix use after free in tpm2_load_context()
If load context command returns with TPM2_RC_HANDLE or TPM2_RC_REFERENCE_H0
then we have use after free in line 114 and double free in 117.

Fixes: 4d57856a21 ("tpm2: add session handle context saving and restoring to the space code")
Cc: stable@vger.kernel.org
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off--by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-05-14 13:56:06 +03:00
Jarkko Sakkinen
4557d4bedc tpm: fix type of a local variable in tpm2_map_command()
The local variable 'handle' should have the type __be32 instead of u32.

Fixes: 745b361e98 ("tpm: infrastructure for TPM spaces")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
2017-10-18 18:28:48 +03:00
James Bottomley
4d57856a21 tpm2: add session handle context saving and restoring to the space code
Sessions are different from transient objects in that their handles
may not be virtualized (because they're used for some hmac
calculations).  Additionally when a session is context saved, a
vestigial memory remains in the TPM and if it is also flushed, that
will be lost and the session context will refuse to load next time, so
the code is updated to flush only transient objects after a context
save.  Add a separate array (chip->session_tbl) to save and restore
sessions by handle.  Use the failure of a context save or load to
signal that the session has been flushed from the TPM and we can
remove its memory from chip->session_tbl.

Sessions are also isolated during each instance of a tpm space.  This
means that spaces shouldn't be able to see each other's sessions and
is enforced by ensuring that a space user may only refer to sessions
handles that are present in their own chip->session_tbl.  Finally when
a space is closed, all the sessions belonging to it should be flushed
so the handles may be re-used by other spaces.

Note that if we get a session save or load error, all sessions are
effectively flushed.  Even though we restore the session buffer, all
the old sessions will refuse to load after the flush and they'll be
purged from our session memory.  This means that while transient
context handling is still soft in the face of errors, session handling
is hard (any failure of the model means all sessions are lost).

Fixes-from: Colin Ian King <colin.king@canonical.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-04-03 22:46:02 +03:00
Jarkko Sakkinen
745b361e98 tpm: infrastructure for TPM spaces
Added an ability to virtualize TPM commands into an isolated context
that we call a TPM space because the word context is already heavily
used in the TPM specification. Both the handle areas and bodies (where
necessary) are virtualized.

The mechanism works by adding a new parameter struct tpm_space to the
tpm_transmit() function. This new structure contains the list of virtual
handles and a buffer of page size (currently) for backing storage.

When tpm_transmit() is called with a struct tpm_space instance it will
execute the following sequence:

1. Take locks.
2. Load transient objects from the backing storage by using ContextLoad
   and map virtual handles to physical handles.
3. Perform the transaction.
4. Save transient objects to backing storage by using ContextSave and
   map resulting physical handle to virtual handle if there is such.

This commit does not implement virtualization support for hmac and
policy sessions.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2017-04-03 22:46:01 +03:00