[WATCHDOG] iTCO_wdt: fix memory corruption when RCBA is disabled by hardware
According to 9.1.33 on p.343 of ICH8.pdf RCBA can be disabled by
hardware if bit 0 of RCBA register is not set.
Perform correct check for this to prevent memory corruption under
some virtual machines where this feature is disabled.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Vasily Averin <vvs@openvz.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index 6284961..6a51edd 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -666,6 +666,11 @@
GCS = RCBA + ICH6_GCS(0x3410). */
if (iTCO_wdt_private.iTCO_version == 2) {
pci_read_config_dword(pdev, 0xf0, &base_address);
+ if ((base_address & 1) == 0) {
+ printk(KERN_ERR PFX "RCBA is disabled by harddware\n");
+ ret = -ENODEV;
+ goto out;
+ }
RCBA = base_address & 0xffffc000;
iTCO_wdt_private.gcs = ioremap((RCBA + 0x3410), 4);
}
@@ -675,7 +680,7 @@
printk(KERN_ERR PFX "failed to reset NO_REBOOT flag, "
"reboot disabled by hardware\n");
ret = -ENODEV; /* Cannot reset NO_REBOOT bit */
- goto out;
+ goto out_unmap;
}
/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
@@ -686,7 +691,7 @@
printk(KERN_ERR PFX
"I/O address 0x%04lx already in use\n", SMI_EN);
ret = -EIO;
- goto out;
+ goto out_unmap;
}
/* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI# */
val32 = inl(SMI_EN);
@@ -742,9 +747,10 @@
release_region(TCOBASE, 0x20);
unreg_smi_en:
release_region(SMI_EN, 4);
-out:
+out_unmap:
if (iTCO_wdt_private.iTCO_version == 2)
iounmap(iTCO_wdt_private.gcs);
+out:
pci_dev_put(iTCO_wdt_private.pdev);
iTCO_wdt_private.ACPIBASE = 0;
return ret;