Commit a430e67d authored Jan 07, 2020 by Tadeusz Struk Committed by Jarkko Sakkinen Jan 08, 2020

tpm: Handle negative priv->response_len in tpm_common_read()



The priv->response_length can hold the size of an response or an negative
error code, and the tpm_common_read() needs to handle both cases correctly.
Changed the type of response_length to signed and accounted for negative
value in tpm_common_read().

Cc: stable@vger.kernel.org
Fixes: d23d1248 ("tpm: fix invalid locking in NONBLOCKING mode")
Reported-by: Laura Abbott <labbott@redhat.com>
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>

parent ae608821

drivers/char/tpm/tpm-dev-common.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -130,7 +130,7 @@ ssize_t tpm_common_read(struct file file, char __user buf,
		priv->response_read = true;

		ret_size = min_t(ssize_t, size, priv->response_length);
		if (!ret_size) {
		if (ret_size <= 0) {
		priv->response_length = 0;
		goto out;
		}

drivers/char/tpm/tpm-dev.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -14,7 +14,7 @@ struct file_priv {
		struct work_struct timeout_work;
		struct work_struct async_work;
		wait_queue_head_t async_wait;
		size_t response_length;
		ssize_t response_length;
		bool response_read;
		bool command_enqueued;

Admin message