| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20121218100023.26480.13240.stgit@zurg>
Date: Tue, 18 Dec 2012 14:00:23 +0400
From: Konstantin Khlebnikov <khlebnikov@...nvz.org>
To: linux-kernel@...r.kernel.org
Cc: Wim Van Sebroeck <wim@...ana.be>, linux-watchdog@...r.kernel.org,
Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: [PATCH] drivers/watchdog/eurotechwdt: handle spurious interrupts on
wrong hardware
"eurotechwdt" hasn't any PCI-ID or DMI checks, thus is can be loaded on any
hardware. On my PC this leads to immediate reboot, because driver got irq right
after registering irq handler. This patch rejects interrupts until device
activation. There is no sense to load this driver without special hardware,
but such bugs blocks mine automatic testing for allmodconfig kernels.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@...nvz.org>
Cc: Wim Van Sebroeck <wim@...ana.be>
Cc: linux-watchdog@...r.kernel.org
Cc: Alan Cox <alan@...rguk.ukuu.org.uk>
---
by default driver uses 10th irq, on my machine it's free:
root@...z:~# cat /proc/interrupts
CPU0 CPU1
0: 187 0 IO-APIC-edge timer
1: 0 8 IO-APIC-edge i8042
7: 2 0 IO-APIC-edge parport0
8: 0 1 IO-APIC-edge rtc0
9: 0 0 IO-APIC-fasteoi acpi
10: 1 0 IO-APIC-edge
14: 1 61 IO-APIC-edge pata_amd
15: 0 0 IO-APIC-edge pata_amd
20: 0 317 IO-APIC-fasteoi snd_hda_intel
22: 0 2 IO-APIC-fasteoi ehci_hcd:usb1, sata_nv
23: 6 3667 IO-APIC-fasteoi ohci_hcd:usb2, sata_nv
41: 93 776888 PCI-MSI-edge eth0
NMI: 0 2 Non-maskable interrupts
LOC: 13293 32610 Local timer interrupts
SPU: 0 0 Spurious interrupts
PMI: 0 2 Performance monitoring interrupts
IWI: 0 0 IRQ work interrupts
RTR: 0 0 APIC ICR read retries
RES: 11427 7619 Rescheduling interrupts
CAL: 182 52 Function call interrupts
TLB: 824 580 TLB shootdowns
TRM: 0 0 Thermal event interrupts
THR: 0 0 Threshold APIC interrupts
MCE: 0 0 Machine check exceptions
MCP: 2 2 Machine check polls
ERR: 1
MIS: 0
---
drivers/watchdog/eurotechwdt.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/watchdog/eurotechwdt.c b/drivers/watchdog/eurotechwdt.c
index cd31b8a..7d24914 100644
--- a/drivers/watchdog/eurotechwdt.c
+++ b/drivers/watchdog/eurotechwdt.c
@@ -65,6 +65,7 @@
static unsigned long eurwdt_is_open;
static int eurwdt_timeout;
static char eur_expect_close;
+static bool eurwdt_is_active;
static DEFINE_SPINLOCK(eurwdt_lock);
/*
@@ -139,6 +140,7 @@ static inline void eurwdt_disable_timer(void)
static void eurwdt_activate_timer(void)
{
eurwdt_disable_timer();
+ eurwdt_is_active = true;
eurwdt_write_reg(WDT_CTRL_REG, 0x01); /* activate the WDT */
eurwdt_write_reg(WDT_OUTPIN_CFG,
!strcmp("int", ev) ? WDT_EVENT_INT : WDT_EVENT_REBOOT);
@@ -164,6 +166,11 @@ static void eurwdt_activate_timer(void)
static irqreturn_t eurwdt_interrupt(int irq, void *dev_id)
{
+ if (!eurwdt_is_active) {
+ pr_crit("spurious interrupt\n");
+ return IRQ_NONE;
+ }
+
pr_crit("timeout WDT timeout\n");
#ifdef ONLY_TESTING
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists