From 84da15169b45f7080e4b1b32f70e68e726e02740 Mon Sep 17 00:00:00 2001 From: Prasad J Pandit Date: Mon, 24 Oct 2016 16:26:55 +0100 Subject: [PATCH] timer: stm32f2xx_timer: add check for prescaler value The STM32F2XX Timer emulator uses a 16 bit prescaler value to limit the timer clock rate. It does that by dividing the timer frequency. If the prescaler 's->tim_psc' was set to be UINT_MAX, it'd lead to divide by zero error. Limit prescaler value to 16 bits to avoid it. Reported-by: Huawei PSIRT Signed-off-by: Prasad J Pandit Message-id: 1476800269-31902-1-git-send-email-ppandit@redhat.com Reviewed-by: Peter Maydell Signed-off-by: Peter Maydell --- hw/timer/stm32f2xx_timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/timer/stm32f2xx_timer.c b/hw/timer/stm32f2xx_timer.c index 8c4c1f9f05..e5f5e14a90 100644 --- a/hw/timer/stm32f2xx_timer.c +++ b/hw/timer/stm32f2xx_timer.c @@ -217,7 +217,7 @@ static void stm32f2xx_timer_write(void *opaque, hwaddr offset, return; case TIM_PSC: timer_val = stm32f2xx_ns_to_ticks(s, now) - s->tick_offset; - s->tim_psc = value; + s->tim_psc = value & 0xFFFF; value = timer_val; break; case TIM_CNT: -- 2.11.4.GIT