diff options
| author | Milan Broz <gmazyland@gmail.com> | 2019-07-04 09:26:15 +0200 |
|---|---|---|
| committer | Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> | 2019-08-05 00:55:00 +0300 |
| commit | 1e5ac6300a07ceecfc70a893ebef3352be21e6f8 (patch) | |
| tree | 2c28562eb49605b7f9bb035235451289808ce1ef | |
| parent | 4b6f23161b4e888e72671e377c32eabe9a8e62fc (diff) | |
tpm: Fix null pointer dereference on chip register error path
If clk_enable is not defined and chip initialization
is canceled code hits null dereference.
Easily reproducible with vTPM init fail:
swtpm chardev --tpmstate dir=nonexistent_dir --tpm2 --vtpm-proxy
BUG: kernel NULL pointer dereference, address: 00000000
...
Call Trace:
tpm_chip_start+0x9d/0xa0 [tpm]
tpm_chip_register+0x10/0x1a0 [tpm]
vtpm_proxy_work+0x11/0x30 [tpm_vtpm_proxy]
process_one_work+0x214/0x5a0
worker_thread+0x134/0x3e0
? process_one_work+0x5a0/0x5a0
kthread+0xd4/0x100
? process_one_work+0x5a0/0x5a0
? kthread_park+0x90/0x90
ret_from_fork+0x19/0x24
Fixes: 719b7d81f204 ("tpm: introduce tpm_chip_start() and tpm_chip_stop()")
Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
| -rw-r--r-- | drivers/char/tpm/tpm-chip.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index d47ad10a35fe..bf868260f435 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -77,6 +77,18 @@ static int tpm_go_idle(struct tpm_chip *chip) return chip->ops->go_idle(chip); } +static void tpm_clk_enable(struct tpm_chip *chip) +{ + if (chip->ops->clk_enable) + chip->ops->clk_enable(chip, true); +} + +static void tpm_clk_disable(struct tpm_chip *chip) +{ + if (chip->ops->clk_enable) + chip->ops->clk_enable(chip, false); +} + /** * tpm_chip_start() - power on the TPM * @chip: a TPM chip to use @@ -89,13 +101,12 @@ int tpm_chip_start(struct tpm_chip *chip) { int ret; - if (chip->ops->clk_enable) - chip->ops->clk_enable(chip, true); + tpm_clk_enable(chip); if (chip->locality == -1) { ret = tpm_request_locality(chip); if (ret) { - chip->ops->clk_enable(chip, false); + tpm_clk_disable(chip); return ret; } } @@ -103,8 +114,7 @@ int tpm_chip_start(struct tpm_chip *chip) ret = tpm_cmd_ready(chip); if (ret) { tpm_relinquish_locality(chip); - if (chip->ops->clk_enable) - chip->ops->clk_enable(chip, false); + tpm_clk_disable(chip); return ret; } @@ -124,8 +134,7 @@ void tpm_chip_stop(struct tpm_chip *chip) { tpm_go_idle(chip); tpm_relinquish_locality(chip); - if (chip->ops->clk_enable) - chip->ops->clk_enable(chip, false); + tpm_clk_disable(chip); } EXPORT_SYMBOL_GPL(tpm_chip_stop); |