hwmon: (dell-smm) Restrict fan control and serial number to CAP_SYS_ADMIN by default

[pandora-kernel.git] / drivers / char / i8k.c

diff --git a/drivers/char/i8k.c b/drivers/char/i8k.c
index 6e40072..50ca7f6 100644 (file)
--- a/drivers/char/i8k.c
+++ b/drivers/char/i8k.c
@@ -63,6 +63,7 @@
 
 static DEFINE_MUTEX(i8k_mutex);
 static char bios_version[4];
+static char bios_machineid[16];
 static struct device *i8k_hwmon_dev;
 
 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
@@ -77,13 +78,13 @@ static int ignore_dmi;
 module_param(ignore_dmi, bool, 0);
 MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
 
-static int restricted;
+static int restricted = true;
 module_param(restricted, bool, 0);
-MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
+MODULE_PARM_DESC(restricted, "Restrict fan control and serial number to CAP_SYS_ADMIN (default: 1)");
 
 static int power_status;
 module_param(power_status, bool, 0600);
-MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
+MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k (default: 0)");
 
 static int fan_mult = I8K_FAN_MULT;
 module_param(fan_mult, int, 0);
@@ -332,8 +333,11 @@ i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
                break;
 
        case I8K_MACHINE_ID:
-               memset(buff, 0, 16);
-               strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff));
+               if (restricted && !capable(CAP_SYS_ADMIN))
+                       return -EPERM;
+
+               memset(buff, 0, sizeof(buff));
+               strlcpy(buff, bios_machineid, sizeof(buff));
                break;
 
        case I8K_FN_STATUS:
@@ -450,7 +454,7 @@ static int i8k_proc_show(struct seq_file *seq, void *offset)
        return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
                          I8K_PROC_FMT,
                          bios_version,
-                         i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
+                         (restricted && !capable(CAP_SYS_ADMIN)) ? "-1" : bios_machineid,
                          cpu_temp,
                          left_fan, right_fan, left_speed, right_speed,
                          ac_power, fn_key);
@@ -664,6 +668,13 @@ static struct dmi_system_id __initdata i8k_dmi_table[] = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
                },
        },
+       {
+               .ident = "Dell XPS421",
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
+               },
+       },
         { }
 };
 
@@ -690,6 +701,8 @@ static int __init i8k_probe(void)
        }
 
        strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION), sizeof(bios_version));
+       strlcpy(bios_machineid, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
+               sizeof(bios_machineid));
 
        /*
         * Get SMM Dell signature