AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

time: Move ktime_t overflow checking into timespec_valid_strict

Browse Source 
Andreas Bombe reported that the added ktime_t overflow checking added to
timespec_valid in commit 4e8b14526c ("time: Improve sanity checking of
timekeeping inputs") was causing problems with X.org because it caused
timeouts larger then KTIME_T to be invalid.

Previously, these large timeouts would be clamped to KTIME_MAX and would
never expire, which is valid.

This patch splits the ktime_t overflow checking into a new
timespec_valid_strict function, and converts the timekeeping codes
internal checking to use this more strict function.

Reported-and-tested-by: Andreas Bombe <aeb@debian.org>
Cc: Zhouping Liu <zliu@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
John Stultz 2012-08-31 13:30:06 -04:00 committed by Linus Torvalds
parent 7a611e69b2
commit cee58483cf
2 changed files with 12 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
include/linux/time.h
View File

@ -125,6 +125,13 @@ static inline bool timespec_valid(const struct timespec *ts)
/* Can't have more nanoseconds then a second */ /* Can't have more nanoseconds then a second */
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return false; return false;
return true;
}
static inline bool timespec_valid_strict(const struct timespec *ts)
{
if (!timespec_valid(ts))
return false;
/* Disallow values that could overflow ktime_t */ /* Disallow values that could overflow ktime_t */
if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX) if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
return false; return false;

10
kernel/time/timekeeping.c
View File

@ -428,7 +428,7 @@ int do_settimeofday(const struct timespec *tv)
struct timespec ts_delta, xt; struct timespec ts_delta, xt;
unsigned long flags; unsigned long flags;
if (!timespec_valid(tv)) if (!timespec_valid_strict(tv))
return -EINVAL; return -EINVAL;
write_seqlock_irqsave(&tk->lock, flags); write_seqlock_irqsave(&tk->lock, flags);
@ -476,7 +476,7 @@ int timekeeping_inject_offset(struct timespec *ts)
/* Make sure the proposed value is valid */ /* Make sure the proposed value is valid */
tmp = timespec_add(tk_xtime(tk), *ts); tmp = timespec_add(tk_xtime(tk), *ts);
if (!timespec_valid(&tmp)) { if (!timespec_valid_strict(&tmp)) {
ret = -EINVAL; ret = -EINVAL;
goto error; goto error;
} }
@ -659,7 +659,7 @@ void __init timekeeping_init(void)
struct timespec now, boot, tmp; struct timespec now, boot, tmp;
read_persistent_clock(&now); read_persistent_clock(&now);
if (!timespec_valid(&now)) { if (!timespec_valid_strict(&now)) {
pr_warn("WARNING: Persistent clock returned invalid value!\n" pr_warn("WARNING: Persistent clock returned invalid value!\n"
" Check your CMOS/BIOS settings.\n"); " Check your CMOS/BIOS settings.\n");
now.tv_sec = 0; now.tv_sec = 0;
@ -667,7 +667,7 @@ void __init timekeeping_init(void)
} }
read_boot_clock(&boot); read_boot_clock(&boot);
if (!timespec_valid(&boot)) { if (!timespec_valid_strict(&boot)) {
pr_warn("WARNING: Boot clock returned invalid value!\n" pr_warn("WARNING: Boot clock returned invalid value!\n"
" Check your CMOS/BIOS settings.\n"); " Check your CMOS/BIOS settings.\n");
boot.tv_sec = 0; boot.tv_sec = 0;
@ -713,7 +713,7 @@ static struct timespec timekeeping_suspend_time;
static void __timekeeping_inject_sleeptime(struct timekeeper *tk, static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
struct timespec *delta) struct timespec *delta)
{ {
if (!timespec_valid(delta)) { if (!timespec_valid_strict(delta)) {
printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid " printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid "
"sleep delta value!\n"); "sleep delta value!\n");
return; return;