Am 23.11.21 um 17:13 schrieb Pali Rohár:
On Saturday 20 November 2021 18:03:18 Armin Wolf wrote:
The second switch-case has no real purpose:
- for I8K_BIOS_VERSION, val does not represent a return value,
making the check for error values unnecessary.
- for I8K_MACHINE_ID, val remains zero, so the error check is
unnecessary too.
Remove the switch-case and move the calls to copy_to_user()
into the first switch-case for I8K_BIOS_VERSION/_MACHINE_ID.
Omit buff[] since data->machineid already contains the string
s/->machineid/->bios_machineid/
with the necessary zero padding.
data is allocated by devm_kzalloc() so data->bios_machineid is really
zero padded.
Tested on a Dell Inspiron 3505.
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
drivers/hwmon/dell-smm-hwmon.c | 30 +++++++++---------------------
1 file changed, 9 insertions(+), 21 deletions(-)
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index 5596c211f38d..b5d1703faa62 100644
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -454,7 +454,6 @@ i8k_ioctl_unlocked(struct file *fp, struct dell_smm_data *data, unsigned int cmd
{
int val = 0;
int speed, err;
- unsigned char buff[16];
int __user *argp = (int __user *)arg;
if (!argp)
@@ -468,15 +467,19 @@ i8k_ioctl_unlocked(struct file *fp, struct dell_smm_data *data, unsigned int cmd
val = (data->bios_version[0] << 16) |
(data->bios_version[1] << 8) | data->bios_version[2];
- break;
+ if (copy_to_user(argp, &val, 4))
+ return -EFAULT;
+
+ return 0;
case I8K_MACHINE_ID:
if (restricted && !capable(CAP_SYS_ADMIN))
return -EPERM;
- strscpy_pad(buff, data->bios_machineid, sizeof(buff));
- break;
+ if (copy_to_user(argp, data->bios_machineid, 16))
What about usage of sizeof(data->bios_machineid) instead of hardcoded
constant 16? And maybe same for constant 4?
For the string yes, but maybe i should change the int to an u32?
+ return -EFAULT;
+ return 0;
case I8K_FN_STATUS:
val = i8k_get_fn_status();
break;
@@ -527,23 +530,8 @@ i8k_ioctl_unlocked(struct file *fp, struct dell_smm_data *data, unsigned int cmd
if (val < 0)
return val;
- switch (cmd) {
- case I8K_BIOS_VERSION:
- if (copy_to_user(argp, &val, 4))
- return -EFAULT;
-
- break;
- case I8K_MACHINE_ID:
- if (copy_to_user(argp, buff, 16))
- return -EFAULT;
-
- break;
- default:
- if (copy_to_user(argp, &val, sizeof(int)))
- return -EFAULT;
-
- break;
- }
+ if (copy_to_user(argp, &val, sizeof(int)))
+ return -EFAULT;
return 0;
}
--
2.30.2
