From: Tzung-Bi Shih tzungbi@kernel.org
[ Upstream commit b20cf3f89c56b5f6a38b7f76a8128bf9f291bbd3 ]
It is possible to peep kernel page's data by providing larger `insize` in struct cros_ec_command[1] when invoking EC host commands.
Fix it by using zeroed memory.
[1]: https://elixir.bootlin.com/linux/v6.2/source/include/linux/platform_data/cro...
Fixes: eda2e30c6684 ("mfd / platform: cros_ec: Miscellaneous character device to talk with the EC") Signed-off-by: Tzung-Bi Shih tzungbi@kernel.org Reviewed-by: Guenter Roeck groeck@chromium.org Link: https://lore.kernel.org/r/20230324010658.1082361-1-tzungbi@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/chrome/cros_ec_chardev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/platform/chrome/cros_ec_chardev.c b/drivers/platform/chrome/cros_ec_chardev.c index 1f5f4a46ab748..4791b62c2923f 100644 --- a/drivers/platform/chrome/cros_ec_chardev.c +++ b/drivers/platform/chrome/cros_ec_chardev.c @@ -285,7 +285,7 @@ static long cros_ec_chardev_ioctl_xcmd(struct cros_ec_dev *ec, void __user *arg) u_cmd.insize > EC_MAX_MSG_BYTES) return -EINVAL;
- s_cmd = kmalloc(sizeof(*s_cmd) + max(u_cmd.outsize, u_cmd.insize), + s_cmd = kzalloc(sizeof(*s_cmd) + max(u_cmd.outsize, u_cmd.insize), GFP_KERNEL); if (!s_cmd) return -ENOMEM;