[PATCH] toshiba_acpi 0.17 from John Belmonte

Fix remote chance of invalid buffer access in write_video.
Support alternate HCI method path (recent "Phoenix BIOS" Toshiba's).
Signal more proc-write errors.
On proc-reads, report errors via printk instead of proc output.
Add log level and driver name prefix to all printk's.
Add missing __init and __exit function attributes.
Be explicit about vars for which code relies on zero-init of BSS.

diff --git a/drivers/acpi/toshiba_acpi.c b/drivers/acpi/toshiba_acpi.c
index 29a6edd1664a4d3bdede3e5a14a1075a6eb3fce4..245685ab850dc87daa3c10a0d1bd0406cbdcbdef 100644 (file)
--- a/drivers/acpi/toshiba_acpi.c
+++ b/drivers/acpi/toshiba_acpi.c
@@ -2,7 +2,7 @@
  *  toshiba_acpi.c - Toshiba Laptop ACPI Extras
  *
  *
- *  Copyright (C) 2002-2003 John Belmonte
+ *  Copyright (C) 2002-2004 John Belmonte
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -33,7 +33,7 @@
  *
  */
 
-#define TOSHIBA_ACPI_VERSION   "0.16"
+#define TOSHIBA_ACPI_VERSION   "0.17"
 #define PROC_INTERFACE_VERSION 1
 
 #include <linux/kernel.h>
@@ -48,9 +48,15 @@ MODULE_AUTHOR("John Belmonte");
 MODULE_DESCRIPTION("Toshiba Laptop ACPI Extras Driver");
 MODULE_LICENSE("GPL");
 
+#define MY_LOGPREFIX "toshiba_acpi: "
+#define MY_ERR KERN_ERR MY_LOGPREFIX
+#define MY_NOTICE KERN_NOTICE MY_LOGPREFIX
+#define MY_INFO KERN_INFO MY_LOGPREFIX
+
 /* Toshiba ACPI method paths */
 #define METHOD_LCD_BRIGHTNESS  "\\_SB_.PCI0.VGA_.LCD_._BCM"
-#define METHOD_HCI             "\\_SB_.VALD.GHCI"
+#define METHOD_HCI_1           "\\_SB_.VALD.GHCI"
+#define METHOD_HCI_2           "\\_SB_.VALZ.GHCI"
 #define METHOD_VIDEO_OUT       "\\_SB_.VALX.DSSX"
 
 /* Toshiba HCI interface definitions
@@ -120,6 +126,16 @@ snscanf(const char* str, int n, const char* format, ...)
 /* acpi interface wrappers
  */
 
+static int
+is_valid_acpi_path(const char* methodName)
+{
+       acpi_handle handle;
+       acpi_status status;
+
+       status = acpi_get_handle(0, (char*)methodName, &handle);
+       return !ACPI_FAILURE(status);
+}
+
 static int
 write_acpi_int(const char* methodName, int val)
 {
@@ -154,6 +170,8 @@ read_acpi_int(const char* methodName, int* pVal)
 }
 #endif
 
+static const char*             method_hci /*= 0*/;
+
 /* Perform a raw HCI call.  Here we don't care about input or output buffer
  * format.
  */
@@ -177,7 +195,7 @@ hci_raw(const u32 in[HCI_WORDS], u32 out[HCI_WORDS])
        results.length = sizeof(out_objs);
        results.pointer = out_objs;
 
-       status = acpi_evaluate_object(0, METHOD_HCI, &params,
+       status = acpi_evaluate_object(0, (char*)method_hci, &params,
                &results);
        if ((status == AE_OK) && (out_objs->package.count <= HCI_WORDS)) {
                for (i = 0; i < out_objs->package.count; ++i) {
@@ -215,7 +233,7 @@ hci_read1(u32 reg, u32* out1, u32* result)
        return status;
 }
 
-static struct proc_dir_entry*  toshiba_proc_dir;
+static struct proc_dir_entry*  toshiba_proc_dir /*= 0*/;
 static int                     force_fan;
 static int                     last_key_event;
 static int                     key_event_valid;
@@ -270,7 +288,7 @@ read_lcd(char* p)
                p += sprintf(p, "brightness_levels:       %d\n",
                        HCI_LCD_BRIGHTNESS_LEVELS);
        } else {
-               p += sprintf(p, "ERROR\n");
+               printk(MY_ERR "Error reading LCD brightness\n");
        }
 
        return p;
@@ -310,7 +328,7 @@ read_video(char* p)
                p += sprintf(p, "crt_out:                 %d\n", is_crt);
                p += sprintf(p, "tv_out:                  %d\n", is_tv);
        } else {
-               p += sprintf(p, "ERROR\n");
+               printk(MY_ERR "Error reading video out status\n");
        }
 
        return p;
@@ -320,25 +338,31 @@ static unsigned long
 write_video(const char* buffer, unsigned long count)
 {
        int value;
-       const char* buffer_end = buffer + count;
+       int remain = count;
        int lcd_out = -1;
        int crt_out = -1;
        int tv_out = -1;
        u32 hci_result;
        int video_out;
 
-       /* scan expression.  Multiple expressions may be delimited with ; */
-       do {
-               if (snscanf(buffer, count, " lcd_out : %i", &value) == 1)
+       /* scan expression.  Multiple expressions may be delimited with ;
+        *
+        *  NOTE: to keep scanning simple, invalid fields are ignored
+        */
+       while (remain) {
+               if (snscanf(buffer, remain, " lcd_out : %i", &value) == 1)
                        lcd_out = value & 1;
-               else if (snscanf(buffer, count, " crt_out : %i", &value) == 1)
+               else if (snscanf(buffer, remain, " crt_out : %i", &value) == 1)
                        crt_out = value & 1;
-               else if (snscanf(buffer, count, " tv_out : %i", &value) == 1)
+               else if (snscanf(buffer, remain, " tv_out : %i", &value) == 1)
                        tv_out = value & 1;
                /* advance to one character past the next ; */
-               do ++buffer;
-               while ((buffer < buffer_end) && (*(buffer-1) != ';'));
-       } while (buffer < buffer_end);
+               do {
+                       ++buffer;
+                       --remain;
+               }
+               while (remain && *(buffer-1) != ';');
+       }
 
        hci_read1(HCI_VIDEO_OUT, &video_out, &hci_result);
        if (hci_result == HCI_SUCCESS) {
@@ -353,6 +377,8 @@ write_video(const char* buffer, unsigned long count)
                 * video setting if something changed. */
                if (new_video_out != video_out)
                        write_acpi_int(METHOD_VIDEO_OUT, new_video_out);
+       } else {
+               return -EFAULT;
        }
 
        return count;
@@ -369,7 +395,7 @@ read_fan(char* p)
                p += sprintf(p, "running:                 %d\n", (value > 0));
                p += sprintf(p, "force_on:                %d\n", force_fan);
        } else {
-               p += sprintf(p, "ERROR\n");
+               printk(MY_ERR "Error reading fan status\n");
        }
 
        return p;
@@ -413,8 +439,9 @@ read_keys(char* p)
                         * some machines where system events sporadically
                         * become disabled. */
                        hci_write1(HCI_SYSTEM_EVENT, 1, &hci_result);
+                       printk(MY_NOTICE "Re-enabled hotkeys\n");
                } else {
-                       p += sprintf(p, "ERROR\n");
+                       printk(MY_ERR "Error reading hotkey status\n");
                        goto end;
                }
        }
@@ -465,7 +492,7 @@ ProcItem proc_items[] =
        { 0             , 0             , 0             },
 };
 
-static acpi_status
+static acpi_status __init
 add_device(void)
 {
        struct proc_dir_entry* proc;
@@ -483,7 +510,7 @@ add_device(void)
        return(AE_OK);
 }
 
-static acpi_status
+static acpi_status __exit
 remove_device(void)
 {
        ProcItem* item;
@@ -497,15 +524,19 @@ static int __init
 toshiba_acpi_init(void)
 {
        acpi_status status = AE_OK;
-       int value;
        u32 hci_result;
 
-       /* simple device detection: try reading an HCI register */
-       hci_read1(HCI_LCD_BRIGHTNESS, &value, &hci_result);
-       if (hci_result != HCI_SUCCESS)
+       /* simple device detection: look for HCI method */
+       if (is_valid_acpi_path(METHOD_HCI_1))
+               method_hci = METHOD_HCI_1;
+       else if (is_valid_acpi_path(METHOD_HCI_2))
+               method_hci = METHOD_HCI_2;
+       else
                return -ENODEV;
 
-       printk("Toshiba Laptop ACPI Extras version %s\n", TOSHIBA_ACPI_VERSION);
+       printk(MY_INFO "Toshiba Laptop ACPI Extras version %s\n",
+               TOSHIBA_ACPI_VERSION);
+       printk(MY_INFO "    HCI method: %s\n", method_hci);
 
        force_fan = 0;
        key_event_valid = 0;