Bug 252539

Summary:

[PATCH] kevent(2): wrong EVFILT_TIMER timeouts when using NOTE_NSECONDS

Product:

Base System

Reporter:

Jan Kokemüller <jan.kokemueller>

Component:

kern

Assignee:

Gordon Bergling <gbe>

Status:

Closed FIXED

Severity:

Affects Some People

CC:

gbe, kevans

Priority:

---

Keywords:

patch

Version:

CURRENT

Hardware:

Any

OS:

Any

See Also:

https://reviews.freebsd.org/D28067

Attachments:

Description	Flags
reproducer	none
patch	none

Description Jan Kokemüller 2021-01-09 09:39:53 UTC

There is a typo in "timer2sbintime" (sys/kern/kern_event.c) when converting NOTE_NSECONDS to sbintime_t. For the nanosecond part US_TO_SBT instead of NS_TO_SBT is used. This results in weird timeout values.

Comment 1 Jan Kokemüller 2021-01-09 09:41:08 UTC

Created attachment 221412 [details]
reproducer

Comment 2 Jan Kokemüller 2021-01-09 09:41:45 UTC

Created attachment 221413 [details]
patch

Comment 3 commit-hook freebsd_committer

2021-01-09 19:08:13 UTC

A commit in branch main references this bug:

URL: https://cgit.FreeBSD.org/src/commit/?id=4d0c33be634a929f323117f04e6b1670776f9e37

commit 4d0c33be634a929f323117f04e6b1670776f9e37
Author:     Jan KokemÃ¼ller <jan.kokemueller@gmail.com>
AuthorDate: 2021-01-09 19:00:25 +0000
Commit:     Gordon Bergling <gbe@FreeBSD.org>
CommitDate: 2021-01-09 19:00:25 +0000

    kevent(2): Bugfix for wrong EVFILT_TIMER timeouts

    When using NOTE_NSECONDS in the kevent(2) API, US_TO_SBT should be
    used instead of NS_TO_SBT, otherwise the timeout results are
    misleading.

    PR:             252539
    Reviewed by:    kevans, kib
    Approved by:    kevans
    MFC after:      3 weeks

 sys/kern/kern_event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comment 4 Gordon Bergling freebsd_committer

2021-01-09 19:10:34 UTC

Commited in 4d0c33be634a929f323117f04e6b1670776f9e37. A MFC is planned for within 3 weeks. Thanks for the patch!

Comment 5 Jan Kokemüller 2021-01-13 09:37:53 UTC

Thank you :)

Comment 6 commit-hook freebsd_committer

2021-01-30 10:14:26 UTC

A commit in branch stable/12 references this bug:

URL: https://cgit.FreeBSD.org/src/commit/?id=6a3ad2d0a7b633bad2bb33f9c4c426dffcc91633

commit 6a3ad2d0a7b633bad2bb33f9c4c426dffcc91633
Author:     Jan KokemÃ¼ller <jan.kokemueller@gmail.com>
AuthorDate: 2021-01-09 19:00:25 +0000
Commit:     Gordon Bergling <gbe@FreeBSD.org>
CommitDate: 2021-01-30 10:11:55 +0000

    kevent(2): Bugfix for wrong EVFILT_TIMER timeouts

    When using NOTE_NSECONDS in the kevent(2) API, US_TO_SBT should be
    used instead of NS_TO_SBT, otherwise the timeout results are
    misleading.

    PR:             252539
    Reviewed by:    kevans, kib
    Approved by:    kevans
    Differential Revision:  https://reviews.freebsd.org/D28067

    (cherry picked from commit 4d0c33be634a929f323117f04e6b1670776f9e37)

 sys/kern/kern_event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comment 7 Gordon Bergling freebsd_committer

2021-01-30 10:16:29 UTC

Committed to HEAD, stable/12 and stable/13.

Thanks for spotting the issue and providing a patch!

Comment 8 commit-hook freebsd_committer

2021-01-30 23:41:37 UTC

A commit in branch stable/11 references this bug:

URL: https://cgit.FreeBSD.org/src/commit/?id=8ce9180c09d93b4ef11859be604ef41173d6dbd1

commit 8ce9180c09d93b4ef11859be604ef41173d6dbd1
Author:     Jan KokemÃ¼ller <jan.kokemueller@gmail.com>
AuthorDate: 2021-01-09 19:00:25 +0000
Commit:     Gordon Bergling <gbe@FreeBSD.org>
CommitDate: 2021-01-30 23:39:58 +0000

    kevent(2): Bugfix for wrong EVFILT_TIMER timeouts

    When using NOTE_NSECONDS in the kevent(2) API, US_TO_SBT should be
    used instead of NS_TO_SBT, otherwise the timeout results are
    misleading.

    PR:             252539
    Reviewed by:    kevans, kib
    Approved by:    kevans
    Differential Revision:  https://reviews.freebsd.org/D28067

    (cherry picked from commit 4d0c33be634a929f323117f04e6b1670776f9e37)
    (cherry picked from commit 6a3ad2d0a7b633bad2bb33f9c4c426dffcc91633)

 sys/kern/kern_event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)