If "s_mem.bytes" is larger than the buffer size it leads to memory
corruption.
Fixes: eda2e30c6684 ("mfd / platform: cros_ec: Miscellaneous character device to talk with the EC")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
drivers/platform/chrome/cros_ec_chardev.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/platform/chrome/cros_ec_chardev.c b/drivers/platform/chrome/cros_ec_chardev.c
index fd33de546aee..2442dce4e208 100644
--- a/drivers/platform/chrome/cros_ec_chardev.c
+++ b/drivers/platform/chrome/cros_ec_chardev.c
@@ -327,6 +327,9 @@ static long cros_ec_chardev_ioctl_readmem(struct cros_ec_dev *ec,
if (copy_from_user(&s_mem, arg, sizeof(s_mem)))
return -EFAULT;
+ if (s_mem.bytes > sizeof(s_mem.buffer))
+ return -EINVAL;
+
num = ec_dev->cmd_readmem(ec_dev, s_mem.offset, s_mem.bytes,
s_mem.buffer);
if (num <= 0)
--
2.35.1
