From 83a06bf50bdf2074b9404951ff60e142d159d93b Mon Sep 17 00:00:00 2001 From: Marcelo Roberto Jimenez Date: Wed, 2 Feb 2011 16:04:02 -0200 Subject: RTC: Prevents a division by zero in kernel code. This patch prevents a user space program from calling the RTC_IRQP_SET ioctl with a negative value of frequency. Also, if this call is make with a zero value of frequency, there would be a division by zero in the kernel code. [jstultz: Also initialize irq_freq to 1 to catch other divbyzero issues] CC: Alessandro Zummo CC: Thomas Gleixner Signed-off-by: Marcelo Roberto Jimenez Signed-off-by: John Stultz --- drivers/rtc/class.c | 1 + drivers/rtc/interface.c | 3 +++ 2 files changed, 4 insertions(+) (limited to 'drivers') diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index 9583cbcc6b7..c404b61386b 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -143,6 +143,7 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev, rtc->id = id; rtc->ops = ops; rtc->owner = owner; + rtc->irq_freq = 1; rtc->max_user_freq = 64; rtc->dev.parent = dev; rtc->dev.class = rtc_class; diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index 925006d3310..a0c01967244 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -464,6 +464,9 @@ int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq) int err = 0; unsigned long flags; + if (freq <= 0) + return -EINVAL; + spin_lock_irqsave(&rtc->irq_task_lock, flags); if (rtc->irq_task != NULL && task == NULL) err = -EBUSY; -- cgit v1.2.3-70-g09d2 From e66a022a80d73b1a5d2e02c9db2c42e8b9853b40 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sat, 11 Dec 2010 20:17:54 +0000 Subject: arm/ixp4xx: Rename FREQ macro to avoid collisions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit FREQ is a ridiculously short name for a platform-specific macro in a generic header, and it now conflicts with an enumeration in the gspca/ov519 driver. Also delete conditional reference to ixp4xx_get_board_tick_rate() which is not defined anywhere. Signed-off-by: Ben Hutchings Signed-off-by: Krzysztof Hałasa --- arch/arm/mach-ixp4xx/common.c | 4 ++-- arch/arm/mach-ixp4xx/include/mach/timex.h | 5 +++-- drivers/input/misc/ixp4xx-beeper.c | 6 +----- 3 files changed, 6 insertions(+), 9 deletions(-) (limited to 'drivers') diff --git a/arch/arm/mach-ixp4xx/common.c b/arch/arm/mach-ixp4xx/common.c index 4dc68d6bb6b..9fd894271d5 100644 --- a/arch/arm/mach-ixp4xx/common.c +++ b/arch/arm/mach-ixp4xx/common.c @@ -432,7 +432,7 @@ static struct clocksource clocksource_ixp4xx = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; -unsigned long ixp4xx_timer_freq = FREQ; +unsigned long ixp4xx_timer_freq = IXP4XX_TIMER_FREQ; EXPORT_SYMBOL(ixp4xx_timer_freq); static void __init ixp4xx_clocksource_init(void) { @@ -496,7 +496,7 @@ static struct clock_event_device clockevent_ixp4xx = { static void __init ixp4xx_clockevent_init(void) { - clockevent_ixp4xx.mult = div_sc(FREQ, NSEC_PER_SEC, + clockevent_ixp4xx.mult = div_sc(IXP4XX_TIMER_FREQ, NSEC_PER_SEC, clockevent_ixp4xx.shift); clockevent_ixp4xx.max_delta_ns = clockevent_delta2ns(0xfffffffe, &clockevent_ixp4xx); diff --git a/arch/arm/mach-ixp4xx/include/mach/timex.h b/arch/arm/mach-ixp4xx/include/mach/timex.h index 2c3f93c3eb7..c9e930f2933 100644 --- a/arch/arm/mach-ixp4xx/include/mach/timex.h +++ b/arch/arm/mach-ixp4xx/include/mach/timex.h @@ -10,6 +10,7 @@ * 66.66... MHz. We do a convulted calculation of CLOCK_TICK_RATE b/c the * timer register ignores the bottom 2 bits of the LATCH value. */ -#define FREQ 66666000 -#define CLOCK_TICK_RATE (((FREQ / HZ & ~IXP4XX_OST_RELOAD_MASK) + 1) * HZ) +#define IXP4XX_TIMER_FREQ 66666000 +#define CLOCK_TICK_RATE \ + (((IXP4XX_TIMER_FREQ / HZ & ~IXP4XX_OST_RELOAD_MASK) + 1) * HZ) diff --git a/drivers/input/misc/ixp4xx-beeper.c b/drivers/input/misc/ixp4xx-beeper.c index 9dfd6e5f786..1f38302a595 100644 --- a/drivers/input/misc/ixp4xx-beeper.c +++ b/drivers/input/misc/ixp4xx-beeper.c @@ -69,11 +69,7 @@ static int ixp4xx_spkr_event(struct input_dev *dev, unsigned int type, unsigned } if (value > 20 && value < 32767) -#ifndef FREQ - count = (ixp4xx_get_board_tick_rate() / (value * 4)) - 1; -#else - count = (FREQ / (value * 4)) - 1; -#endif + count = (IXP4XX_TIMER_FREQ / (value * 4)) - 1; ixp4xx_spkr_control(pin, count); -- cgit v1.2.3-70-g09d2