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yaml
---
r: 54705
b: refs/heads/master
c: 35bab75
h: refs/heads/master
i:
  54703: fb702a6
v: v3
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Adrian Bunk authored and Linus Torvalds committed May 8, 2007
1 parent 2f1ad2b commit cbb209e
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2 changes: 1 addition & 1 deletion [refs]
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@@ -1,2 +1,2 @@
---
refs/heads/master: b3561ea9462b33a0bf824b4ca19a1ae84db81210
refs/heads/master: 35bab756b49bd148760a3bbd3c907cd74754dbb4
12 changes: 0 additions & 12 deletions trunk/Documentation/feature-removal-schedule.txt
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Expand Up @@ -117,18 +117,6 @@ Who: Adrian Bunk <bunk@stusta.de>

---------------------------

What: Usage of invalid timevals in setitimer
When: March 2007
Why: POSIX requires to validate timevals in the setitimer call. This
was never done by Linux. The invalid (e.g. negative timevals) were
silently converted to more or less random timeouts and intervals.
Until the removal a per boot limited number of warnings is printed
and the timevals are sanitized.

Who: Thomas Gleixner <tglx@linutronix.de>

---------------------------

What: Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports
(temporary transition config option provided until then)
The transition config option will also be removed at the same time.
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59 changes: 3 additions & 56 deletions trunk/kernel/itimer.c
Original file line number Diff line number Diff line change
Expand Up @@ -137,60 +137,12 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer)
return HRTIMER_NORESTART;
}

/*
* We do not care about correctness. We just sanitize the values so
* the ktime_t operations which expect normalized values do not
* break. This converts negative values to long timeouts similar to
* the code in kernel versions < 2.6.16
*
* Print a limited number of warning messages when an invalid timeval
* is detected.
*/
static void fixup_timeval(struct timeval *tv, int interval)
{
static int warnlimit = 10;
unsigned long tmp;

if (warnlimit > 0) {
warnlimit--;
printk(KERN_WARNING
"setitimer: %s (pid = %d) provided "
"invalid timeval %s: tv_sec = %ld tv_usec = %ld\n",
current->comm, current->pid,
interval ? "it_interval" : "it_value",
tv->tv_sec, (long) tv->tv_usec);
}

tmp = tv->tv_usec;
if (tmp >= USEC_PER_SEC) {
tv->tv_usec = tmp % USEC_PER_SEC;
tv->tv_sec += tmp / USEC_PER_SEC;
}

tmp = tv->tv_sec;
if (tmp > LONG_MAX)
tv->tv_sec = LONG_MAX;
}

/*
* Returns true if the timeval is in canonical form
*/
#define timeval_valid(t) \
(((t)->tv_sec >= 0) && (((unsigned long) (t)->tv_usec) < USEC_PER_SEC))

/*
* Check for invalid timevals, sanitize them and print a limited
* number of warnings.
*/
static void check_itimerval(struct itimerval *value) {

if (unlikely(!timeval_valid(&value->it_value)))
fixup_timeval(&value->it_value, 0);

if (unlikely(!timeval_valid(&value->it_interval)))
fixup_timeval(&value->it_interval, 1);
}

int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
{
struct task_struct *tsk = current;
Expand All @@ -200,15 +152,10 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)

/*
* Validate the timevals in value.
*
* Note: Although the spec requires that invalid values shall
* return -EINVAL, we just fixup the value and print a limited
* number of warnings in order not to break users of this
* historical misfeature.
*
* Scheduled for replacement in March 2007
*/
check_itimerval(value);
if (!timeval_valid(&value->it_value) ||
!timeval_valid(&value->it_interval))
return -EINVAL;

switch (which) {
case ITIMER_REAL:
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