Bug 252539 - [PATCH] kevent(2): wrong EVFILT_TIMER timeouts when using NOTE_NSECONDS
Summary: [PATCH] kevent(2): wrong EVFILT_TIMER timeouts when using NOTE_NSECONDS
Status: Closed FIXED
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: Any Any
: --- Affects Some People
Assignee: Gordon Bergling
URL:
Keywords: patch
Depends on:
Blocks:
 
Reported: 2021-01-09 09:39 UTC by Jan Kokemüller
Modified: 2021-01-30 23:41 UTC (History)
2 users (show)

See Also:

Attachments
reproducer (1.42 KB, text/plain)
2021-01-09 09:41 UTC, Jan Kokemüller 		no flags Details
patch (704 bytes, patch)
2021-01-09 09:41 UTC, Jan Kokemüller 		no flags Details | Diff
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
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 freebsd_triage 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 Kokemüller <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 freebsd_triage 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 freebsd_triage 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 Kokemüller <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 freebsd_triage 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 freebsd_triage 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 Kokemüller <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(-)