Commit fb8f7ba0 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Wim Van Sebroeck

[WATCHDOG] Semi-typical watchdog bug re early misc_register()

It seems that some watchdog drivers are doing following mistake:

	rv = misc_register();
	if (rv < 0)
		return rv;
	rv = request_region();
	if (rv < 0) {
		misc_deregister();
		return rv;
	}

But, right after misc_register() returns, misc device can be opened and
ioctls interacting with hardware issued, and driver can do outb() to
port it doesn't own yet, because request_region() is still pending.

Here is my patch, compile-tested only.
Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: default avatarWim Van Sebroeck <wim@iguana.be>
parent 0e94f2ee
......@@ -220,17 +220,17 @@ static int __devinit cpu5wdt_init(void)
if ( verbose )
printk(KERN_DEBUG PFX "port=0x%x, verbose=%i\n", port, verbose);
if ( (err = misc_register(&cpu5wdt_misc)) < 0 ) {
printk(KERN_ERR PFX "misc_register failed\n");
goto no_misc;
}
if ( !request_region(port, CPU5WDT_EXTENT, PFX) ) {
printk(KERN_ERR PFX "request_region failed\n");
err = -EBUSY;
goto no_port;
}
if ( (err = misc_register(&cpu5wdt_misc)) < 0 ) {
printk(KERN_ERR PFX "misc_register failed\n");
goto no_misc;
}
/* watchdog reboot? */
val = inb(port + CPU5WDT_STATUS_REG);
val = (val >> 2) & 1;
......@@ -250,9 +250,9 @@ static int __devinit cpu5wdt_init(void)
return 0;
no_port:
misc_deregister(&cpu5wdt_misc);
no_misc:
release_region(port, CPU5WDT_EXTENT);
no_port:
return err;
}
......
......@@ -413,17 +413,10 @@ static int __init eurwdt_init(void)
{
int ret;
ret = misc_register(&eurwdt_miscdev);
if (ret) {
printk(KERN_ERR "eurwdt: can't misc_register on minor=%d\n",
WATCHDOG_MINOR);
goto out;
}
ret = request_irq(irq, eurwdt_interrupt, IRQF_DISABLED, "eurwdt", NULL);
if(ret) {
printk(KERN_ERR "eurwdt: IRQ %d is not free.\n", irq);
goto outmisc;
goto out;
}
if (!request_region(io, 2, "eurwdt")) {
......@@ -438,6 +431,13 @@ static int __init eurwdt_init(void)
goto outreg;
}
ret = misc_register(&eurwdt_miscdev);
if (ret) {
printk(KERN_ERR "eurwdt: can't misc_register on minor=%d\n",
WATCHDOG_MINOR);
goto outreboot;
}
eurwdt_unlock_chip();
ret = 0;
......@@ -448,14 +448,14 @@ static int __init eurwdt_init(void)
out:
return ret;
outreboot:
unregister_reboot_notifier(&eurwdt_notifier);
outreg:
release_region(io, 2);
outirq:
free_irq(irq, NULL);
outmisc:
misc_deregister(&eurwdt_miscdev);
goto out;
}
......
......@@ -367,18 +367,17 @@ static int __init ibmasr_init(void)
if (!asr_type)
return -ENODEV;
rc = asr_get_base_address();
if (rc)
return rc;
rc = misc_register(&asr_miscdev);
if (rc < 0) {
release_region(asr_base, asr_length);
printk(KERN_ERR PFX "failed to register misc device\n");
return rc;
}
rc = asr_get_base_address();
if (rc) {
misc_deregister(&asr_miscdev);
return rc;
}
return 0;
}
......
......@@ -440,13 +440,6 @@ static int __init zf_init(void)
spin_lock_init(&zf_lock);
spin_lock_init(&zf_port_lock);
ret = misc_register(&zf_miscdev);
if (ret){
printk(KERN_ERR "can't misc_register on minor=%d\n",
WATCHDOG_MINOR);
goto out;
}
if(!request_region(ZF_IOBASE, 3, "MachZ ZFL WDT")){
printk(KERN_ERR "cannot reserve I/O ports at %d\n",
ZF_IOBASE);
......@@ -461,16 +454,23 @@ static int __init zf_init(void)
goto no_reboot;
}
ret = misc_register(&zf_miscdev);
if (ret){
printk(KERN_ERR "can't misc_register on minor=%d\n",
WATCHDOG_MINOR);
goto no_misc;
}
zf_set_status(0);
zf_set_control(0);
return 0;
no_misc:
unregister_reboot_notifier(&zf_notifier);
no_reboot:
release_region(ZF_IOBASE, 3);
no_region:
misc_deregister(&zf_miscdev);
out:
return ret;
}
......
......@@ -333,18 +333,17 @@ static int __init sbc8360_init(void)
int res;
unsigned long int mseconds = 60000;
spin_lock_init(&sbc8360_lock);
res = misc_register(&sbc8360_miscdev);
if (res) {
printk(KERN_ERR PFX "failed to register misc device\n");
goto out_nomisc;
if (timeout < 0 || timeout > 63) {
printk(KERN_ERR PFX "Invalid timeout index (must be 0-63).\n");
res = -EINVAL;
goto out;
}
if (!request_region(SBC8360_ENABLE, 1, "SBC8360")) {
printk(KERN_ERR PFX "ENABLE method I/O %X is not available.\n",
SBC8360_ENABLE);
res = -EIO;
goto out_noenablereg;
goto out;
}
if (!request_region(SBC8360_BASETIME, 1, "SBC8360")) {
printk(KERN_ERR PFX
......@@ -360,10 +359,11 @@ static int __init sbc8360_init(void)
goto out_noreboot;
}
if (timeout < 0 || timeout > 63) {
printk(KERN_ERR PFX "Invalid timeout index (must be 0-63).\n");
res = -EINVAL;
goto out_noreboot;
spin_lock_init(&sbc8360_lock);
res = misc_register(&sbc8360_miscdev);
if (res) {
printk(KERN_ERR PFX "failed to register misc device\n");
goto out_nomisc;
}
wd_margin = wd_times[timeout][0];
......@@ -383,13 +383,13 @@ static int __init sbc8360_init(void)
return 0;
out_nomisc:
unregister_reboot_notifier(&sbc8360_notifier);
out_noreboot:
release_region(SBC8360_ENABLE, 1);
release_region(SBC8360_BASETIME, 1);
out_noenablereg:
out_nobasetimereg:
misc_deregister(&sbc8360_miscdev);
out_nomisc:
release_region(SBC8360_ENABLE, 1);
out:
return res;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment