From c08b8a49100715b20e6f7c997e992428b5e06078 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 25 Mar 2006 03:06:33 -0800 Subject: [PATCH] sys_alarm() unsigned signed conversion fixup alarm() calls the kernel with an unsigend int timeout in seconds. The value is stored in the tv_sec field of a struct timeval to setup the itimer. The tv_sec field of struct timeval is of type long, which causes the tv_sec value to be negative on 32 bit machines if seconds > INT_MAX. Before the hrtimer merge (pre 2.6.16) such a negative value was converted to the maximum jiffies timeout by the timeval_to_jiffies conversion. It's not clear whether this was intended or just happened to be done by the timeval_to_jiffies code. hrtimers expect a timeval in canonical form and treat a negative timeout as already expired. This breaks the legitimate usage of alarm() with a timeout value > INT_MAX seconds. For 32 bit machines it is therefor necessary to limit the internal seconds value to avoid API breakage. Instead of doing this in all implementations of sys_alarm the duplicated sys_alarm code is moved into a common function in itimer.c Signed-off-by: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/mips/kernel/sysirix.c | 22 +--------------------- 1 file changed, 1 insertion(+), 21 deletions(-) (limited to 'arch/mips') diff --git a/arch/mips/kernel/sysirix.c b/arch/mips/kernel/sysirix.c index 0fc3730a294f..5407b784cd01 100644 --- a/arch/mips/kernel/sysirix.c +++ b/arch/mips/kernel/sysirix.c @@ -645,27 +645,7 @@ static inline void getitimer_real(struct itimerval *value) asmlinkage unsigned int irix_alarm(unsigned int seconds) { - struct itimerval it_new, it_old; - unsigned int oldalarm; - - if (!seconds) { - getitimer_real(&it_old); - del_timer(¤t->real_timer); - } else { - it_new.it_interval.tv_sec = it_new.it_interval.tv_usec = 0; - it_new.it_value.tv_sec = seconds; - it_new.it_value.tv_usec = 0; - do_setitimer(ITIMER_REAL, &it_new, &it_old); - } - oldalarm = it_old.it_value.tv_sec; - /* - * ehhh.. We can't return 0 if we have an alarm pending ... - * And we'd better return too much than too little anyway - */ - if (it_old.it_value.tv_usec) - oldalarm++; - - return oldalarm; + return alarm_setitimer(seconds); } asmlinkage int irix_pause(void) -- cgit v1.2.3