This is a note to let you know that I've just added the patch titled
platform/chrome: cros_ec_chardev: fix kernel data leak from ioctl
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
platform-chrome-cros_ec_chardev-fix-kernel-data-leak.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3be9eb4450579f7e131db7d9b2e3ccdec0e69495
Author: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
Date: Fri Mar 24 09:06:58 2023 +0800
platform/chrome: cros_ec_chardev: fix kernel data leak from ioctl
[ 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/cros_ec_proto.h#L74
Fixes: eda2e30c6684 ("mfd / platform: cros_ec: Miscellaneous character device to talk with the EC")
Signed-off-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
Reviewed-by: Guenter Roeck <groeck@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230324010658.1082361-1-tzungbi@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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;
