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author | peter <peter@FreeBSD.org> | 1997-05-10 12:00:03 +0000 |
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committer | peter <peter@FreeBSD.org> | 1997-05-10 12:00:03 +0000 |
commit | 466cea7091e7b9d457e1deb200495768bcfc1d93 (patch) | |
tree | e62521c365d209d717500ea79bf41aeb8d94539c /sys/kern/kern_time.c | |
parent | bb3545a8cab7e4b6b05a9082658414f88edeaab2 (diff) | |
download | FreeBSD-src-466cea7091e7b9d457e1deb200495768bcfc1d93.zip FreeBSD-src-466cea7091e7b9d457e1deb200495768bcfc1d93.tar.gz |
Fixes from Bruce:
Serious:
- An important timevalfix() in settime[ofday]() was lost.
Not so serious:
- There was a race initializing `delta' in the check for setting the
time backwards.
- The `#ifdef notyet' check for setting the time more than a day forwards
was back to front.
[[I deleted the code, it's useless because of iteration - Peter]]
- The timespec was not checked for validity in clock_settime().
- The timespec was not fully checked for validity in nanotime(). The
check in itimerfix() is too late, since the conversion from a timespec
to a timeval may overflow.
- A garbage timeval was checked in settimeofday() for the (uap->tv == NULL
&& uap->tzp != NULL) case. I added the broken check this some time ago.
Cosmetic:
- The "inadvertantly (sic) sleeping forever" test always failed. hzto()
always returns >= 1.
- The style wasn't very KNFish. (I only changed new code.)
Submitted by: bde
Diffstat (limited to 'sys/kern/kern_time.c')
-rw-r--r-- | sys/kern/kern_time.c | 123 |
1 files changed, 64 insertions, 59 deletions
diff --git a/sys/kern/kern_time.c b/sys/kern/kern_time.c index b5fbf0f..19cf8ee 100644 --- a/sys/kern/kern_time.c +++ b/sys/kern/kern_time.c @@ -31,7 +31,7 @@ * SUCH DAMAGE. * * @(#)kern_time.c 8.1 (Berkeley) 6/10/93 - * $Id: kern_time.c,v 1.24 1997/05/10 05:29:41 brian Exp $ + * $Id: kern_time.c,v 1.25 1997/05/10 06:02:29 brian Exp $ */ #include <sys/param.h> @@ -42,6 +42,7 @@ #include <sys/systm.h> #include <sys/sysent.h> #include <sys/proc.h> +#include <sys/time.h> #include <sys/vnode.h> struct timezone tz; @@ -56,8 +57,8 @@ struct timezone tz; * timers when they expire. */ -static void timevalfix __P((struct timeval *)); static int settime __P((struct timeval *)); +static void timevalfix __P((struct timeval *)); static int settime(tv) @@ -68,17 +69,15 @@ settime(tv) int s; /* - * Must not set clock backwards in secure mode + * Must not set clock backwards in highly secure mode. */ + s = splclock(); delta.tv_sec = tv->tv_sec - time.tv_sec; delta.tv_usec = tv->tv_usec - time.tv_usec; + splx(s); timevalfix(&delta); if (delta.tv_sec < 0 && securelevel > 1) return (EPERM); -#ifdef notyet - if (delta.tv_sec < 86400 && securelevel > 0) - return (EPERM); -#endif s = splclock(); /* @@ -98,6 +97,7 @@ settime(tv) * adjustments. */ (void) splsoftclock(); + timevalfix(&delta); timevaladd(&boottime, &delta); timevaladd(&runtime, &delta); for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) @@ -117,6 +117,7 @@ struct clock_gettime_args { struct timespec *tp; }; #endif + /* ARGSUSED */ int clock_gettime(p, uap, retval) @@ -124,18 +125,14 @@ clock_gettime(p, uap, retval) struct clock_gettime_args *uap; register_t *retval; { - clockid_t clock_id; struct timeval atv; struct timespec ats; - clock_id = SCARG(uap, clock_id); - if (clock_id != CLOCK_REALTIME) + if (SCARG(uap, clock_id) != CLOCK_REALTIME) return (EINVAL); - microtime(&atv); TIMEVAL_TO_TIMESPEC(&atv, &ats); - - return copyout(&ats, SCARG(uap, tp), sizeof(ats)); + return (copyout(&ats, SCARG(uap, tp), sizeof(ats))); } #ifndef _SYS_SYSPROTO_H_ @@ -144,6 +141,7 @@ struct clock_settime_args { const struct timespec *tp; }; #endif + /* ARGSUSED */ int clock_settime(p, uap, retval) @@ -151,26 +149,22 @@ clock_settime(p, uap, retval) struct clock_settime_args *uap; register_t *retval; { - clockid_t clock_id; struct timeval atv; struct timespec ats; int error; if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) return (error); - - clock_id = SCARG(uap, clock_id); - if (clock_id != CLOCK_REALTIME) + if (SCARG(uap, clock_id) != CLOCK_REALTIME) return (EINVAL); - if ((error = copyin(SCARG(uap, tp), &ats, sizeof(ats))) != 0) return (error); - + if (atv.tv_usec < 0 || ats.tv_nsec >= 1000000000) + return (EINVAL); TIMESPEC_TO_TIMEVAL(&atv, &ats); if ((error = settime(&atv))) return (error); - - return 0; + return (0); } #ifndef _SYS_SYSPROTO_H_ @@ -179,28 +173,25 @@ struct clock_getres_args { struct timespec *tp; }; #endif + int clock_getres(p, uap, retval) struct proc *p; struct clock_getres_args *uap; register_t *retval; { - clockid_t clock_id; struct timespec ts; - int error = 0; + int error; - clock_id = SCARG(uap, clock_id); - if (clock_id != CLOCK_REALTIME) + if (SCARG(uap, clock_id) != CLOCK_REALTIME) return (EINVAL); - + error = 0; if (SCARG(uap, tp)) { ts.tv_sec = 0; ts.tv_nsec = 1000000000 / hz; - - error = copyout(&ts, SCARG(uap, tp), sizeof (ts)); + error = copyout(&ts, SCARG(uap, tp), sizeof(ts)); } - - return error; + return (error); } #ifndef _SYS_SYSPROTO_H_ @@ -209,6 +200,7 @@ struct nanosleep_args { struct timespec *rmtp; }; #endif + /* ARGSUSED */ int nanosleep(p, uap, retval) @@ -217,28 +209,26 @@ nanosleep(p, uap, retval) register_t *retval; { static int nanowait; - struct timespec rqt; - struct timespec rmt; + struct timespec rmt, rqt; struct timeval atv, utv; - int error, s, timo; + int error, error2, s, timo; - error = copyin((caddr_t)SCARG(uap, rqtp), (caddr_t)&rqt, - sizeof(struct timespec)); + error = copyin(SCARG(uap, rqtp), &rqt, sizeof(rqt)); if (error) return (error); - + if (rqt.tv_nsec < 0 || rqt.tv_nsec >= 1000000000) + return (EINVAL); TIMESPEC_TO_TIMEVAL(&atv, &rqt) if (itimerfix(&atv)) return (EINVAL); + /* + * XXX this is not as careful as settimeofday() about minimising + * interrupt latency. The hzto() interface is inconvenient as usual. + */ s = splclock(); timevaladd(&atv, &time); timo = hzto(&atv); - /* - * Avoid inadvertantly sleeping forever - */ - if (timo == 0) - timo = 1; splx(s); error = tsleep(&nanowait, PWAIT | PCATCH, "nanosleep", timo); @@ -246,26 +236,39 @@ nanosleep(p, uap, retval) error = EINTR; if (error == EWOULDBLOCK) error = 0; - if (SCARG(uap, rmtp)) { - int error; - + /*- + * XXX this is unnecessary and possibly wrong if the timeout + * expired. Then the remaining time should be zero. If the + * calculation gives a nonzero value, then we have a bug. + * (1) if settimeofday() was called, then the calculation is + * probably wrong, since `time' has probably become + * inconsistent with the ending time `atv'. + * (2) otherwise, our calculation of `timo' was wrong, perhaps + * due to `tick' being wrong when hzto() was called or + * changing afterwards (it can be wrong or change due to + * hzto() not knowing about adjtime(2) or tickadj(8)). + * Then we should be sleeping again instead instead of + * returning. Rounding up in hzto() probably fixes this + * problem for small timeouts, but the absolute error may + * be large for large timeouts. + */ s = splclock(); utv = time; splx(s); - timevalsub(&atv, &utv); if (atv.tv_sec < 0) timerclear(&atv); - TIMEVAL_TO_TIMESPEC(&atv, &rmt); - error = copyout((caddr_t)&rmt, (caddr_t)SCARG(uap, rmtp), - sizeof(rmt)); - if (error) - return (error); - } - return error; + /* + * XXX should we test for addressibility before sleeping? + */ + error2 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt)); + if (error2) + return (error2); + } + return (error); } @@ -310,18 +313,20 @@ settimeofday(p, uap, retval) struct settimeofday_args *uap; int *retval; { - struct timeval atv, delta; + struct timeval atv; struct timezone atz; - int error, s; + int error; if ((error = suser(p->p_ucred, &p->p_acflag))) return (error); /* Verify all parameters before changing time. */ - if (uap->tv && - (error = copyin((caddr_t)uap->tv, (caddr_t)&atv, sizeof(atv)))) - return (error); - if (atv.tv_usec < 0 || atv.tv_usec >= 1000000) - return (EINVAL); + if (uap->tv) { + if ((error = copyin((caddr_t)uap->tv, (caddr_t)&atv, + sizeof(atv)))) + return (error); + if (atv.tv_usec < 0 || atv.tv_usec >= 1000000) + return (EINVAL); + } if (uap->tzp && (error = copyin((caddr_t)uap->tzp, (caddr_t)&atz, sizeof(atz)))) return (error); |