kernel.git/drivers/char/tpm/tpm2-cmd.c, branch master

tpm2-sessions: Open code tpm_buf_append_hmac_session()

2025-12-05T04:42:51Z

Open code 'tpm_buf_append_hmac_session_opt' to the call site, as it only masks a call sequence and does otherwise nothing particularly useful. Signed-off-by: Jarkko Sakkinen Reviewed-by: Jonathan McDowell

tpm2-sessions: Remove 'attributes' parameter from tpm_buf_append_auth

2025-12-05T04:42:51Z

Remove 'attributes' parameter from 'tpm_buf_append_auth', as it is not used by the function. Fixes: 27184f8905ba ("tpm: Opt-in in disable PCR integrity protection") Signed-off-by: Jarkko Sakkinen Reviewed-by: Jonathan McDowell

tpm2-sessions: Fix tpm2_read_public range checks

2025-12-05T04:42:44Z

tpm2_read_public() has some rudimentary range checks but the function does not ensure that the response buffer has enough bytes for the full TPMT_HA payload. Re-implement the function with necessary checks and validation, and return name and name size for all handle types back to the caller. Cc: stable@vger.kernel.org # v6.10+ Fixes: d0a25bb961e6 ("tpm: Add HMAC session name/handle append") Signed-off-by: Jarkko Sakkinen Reviewed-by: Jonathan McDowell

tpm2-sessions: Fix out of range indexing in name_size

2025-12-05T04:31:07Z

'name_size' does not have any range checks, and it just directly indexes with TPM_ALG_ID, which could lead into memory corruption at worst. Address the issue by only processing known values and returning -EINVAL for unrecognized values. Make also 'tpm_buf_append_name' and 'tpm_buf_fill_hmac_session' fallible so that errors are detected before causing any spurious TPM traffic. End also the authorization session on failure in both of the functions, as the session state would be then by definition corrupted. Cc: stable@vger.kernel.org # v6.10+ Fixes: 1085b8276bb4 ("tpm: Add the rest of the session HMAC API") Reviewed-by: Jonathan McDowell Signed-off-by: Jarkko Sakkinen

tpm: Cap the number of PCR banks

2025-12-03T20:55:28Z

tpm2_get_pcr_allocation() does not cap any upper limit for the number of banks. Cap the limit to eight banks so that out of bounds values coming from external I/O cause on only limited harm. Cc: stable@vger.kernel.org # v5.10+ Fixes: bcfff8384f6c ("tpm: dynamically allocate the allocated_banks array") Tested-by: Lai Yi Reviewed-by: Jonathan McDowell Reviewed-by: Roberto Sassu Signed-off-by: Jarkko Sakkinen

KEYS: trusted: Replace a redundant instance of tpm2_hash_map

2025-11-29T20:57:30Z

'trusted_tpm2' duplicates 'tpm2_hash_map' originally part of the TPN driver, which is suboptimal. Implement and export `tpm2_find_hash_alg()` in the driver, and substitute the redundant code in 'trusted_tpm2' with a call to the new function. Reviewed-by: Jonathan McDowell Signed-off-by: Jarkko Sakkinen

tpm: use a map for tpm2_calc_ordinal_duration()

2025-10-10T05:21:45Z

The current shenanigans for duration calculation introduce too much complexity for a trivial problem, and further the code is hard to patch and maintain. Address these issues with a flat look-up table, which is easy to understand and patch. If leaf driver specific patching is required in future, it is easy enough to make a copy of this table during driver initialization and add the chip parameter back. 'chip->duration' is retained for TPM 1.x. As the first entry for this new behavior address TCG spec update mentioned in this issue: https://github.com/raspberrypi/linux/issues/7054 Therefore, for TPM_SelfTest the duration is set to 3000 ms. This does not categorize a as bug, given that this is introduced to the spec after the feature was originally made. Reviewed-by: Serge Hallyn Signed-off-by: Jarkko Sakkinen

tpm: Lazily flush auth session when getting random data

2025-03-27T13:34:04Z

Lazy flushing of TPM auth sessions was introduced to speed up IMA measurments into the TPM. Make use of it in tpm2_get_random as well, which has the added benefit of not needlessly cleaning up the session that IMA is using when there are no userspace accesses taking place. Command trace before for every call: hwrng (0x00000161): 14 (52965242 ns) hwrng (0x00000176): 48 (161612432 ns) hwrng (0x00000165): 10 (2410494 ns) hwrng (0x0000017B): 117 (70699883 ns) hwrng (0x0000017B): 117 (70959666 ns) hwrng (0x00000165): 10 (2756827 ns) After, with repeated calls showing no setup: hwrng (0x00000161): 14 (53044582 ns) hwrng (0x00000176): 48 (160491333 ns) hwrng (0x00000165): 10 (2408220 ns) hwrng (0x0000017B): 117 (70695037 ns) hwrng (0x0000017B): 117 (70994984 ns) hwrng (0x0000017B): 117 (70195388 ns) hwrng (0x0000017B): 117 (70973835 ns) Signed-off-by: Jonathan McDowell Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen

tpm: Opt-in in disable PCR integrity protection

2024-11-13T19:10:45Z

The initial HMAC session feature added TPM bus encryption and/or integrity protection to various in-kernel TPM operations. This can cause performance bottlenecks with IMA, as it heavily utilizes PCR extend operations. In order to mitigate this performance issue, introduce a kernel command-line parameter to the TPM driver for disabling the integrity protection for PCR extend operations (i.e. TPM2_PCR_Extend). Cc: James Bottomley Link: https://lore.kernel.org/linux-integrity/20241015193916.59964-1-zohar@linux.ibm.com/ Fixes: 6519fea6fd37 ("tpm: add hmac checks to tpm2_pcr_extend()") Tested-by: Mimi Zohar Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu Co-developed-by: Mimi Zohar Signed-off-by: Mimi Zohar Signed-off-by: Jarkko Sakkinen

tpm: Open code tpm_buf_parameters()

2024-05-28T10:03:57Z

With only single call site, this makes no sense (slipped out of the radar during the review). Open code and document the action directly to the site, to make it more readable. Fixes: 1b6d7f9eb150 ("tpm: add session encryption protection to tpm2_get_random()") Signed-off-by: Jarkko Sakkinen