Commit 628044aa authored by Patryk Duda's avatar Patryk Duda Committed by ZhangPeng
Browse files

platform/chrome: cros_ec_proto: Lock device when updating MKBP version 

stable inclusion
from stable-v6.6.45
commit b8774d3137e55b58f3949d4561b3c69dffbdc336
bugzilla: https://gitee.com/openeuler/kernel/issues/IAJEIR

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b8774d3137e55b58f3949d4561b3c69dffbdc336



--------------------------------

commit df615907f1bf907260af01ccb904d0e9304b5278 upstream.

The cros_ec_get_host_command_version_mask() function requires that the
caller must have ec_dev->lock mutex before calling it. This requirement
was not met and as a result it was possible that two commands were sent
to the device at the same time.

The problem was observed while using UART backend which doesn't use any
additional locks, unlike SPI backend which locks the controller until
response is received.

Fixes: f74c7557 ("platform/chrome: cros_ec_proto: Update version on GET_NEXT_EVENT failure")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarPatryk Duda <patrykd@google.com>
Link: https://lore.kernel.org/r/20240730104425.607083-1-patrykd@google.com


Signed-off-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
parent 83a80130

drivers/platform/chrome/cros_ec_proto.c

+2 −0
Original line number Diff line number Diff line
@@ -805,9 +805,11 @@ int cros_ec_get_next_event(struct cros_ec_device *ec_dev, 
	if (ret == -ENOPROTOOPT) {

		dev_dbg(ec_dev->dev,

			"GET_NEXT_EVENT returned invalid version error.\n");

		mutex_lock(&ec_dev->lock);

		ret = cros_ec_get_host_command_version_mask(ec_dev,

							EC_CMD_GET_NEXT_EVENT,

							&ver_mask);

		mutex_unlock(&ec_dev->lock);

		if (ret < 0 || ver_mask == 0)

			/*

			 * Do not change the MKBP supported version if we can't