view auto/os/freebsd @ 9300:5be23505292b default tip

SSI: fixed incorrect or duplicate stub output. Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set if there are data in the first buffer sent in the subrequest. As a result, following the change mentioned this flag cannot be used to prevent duplicate ngx_http_ssi_stub_output() calls, since it is not set if there was already some output, but the first buffer was empty. Still, when there are multiple subrequests, even an empty subrequest response might be delayed by the postpone filter, leading to a second call of ngx_http_ssi_stub_output() during finalization from ngx_http_writer() the subreqest buffers are released by the postpone filter. Since r->request_output is not set after the first call, this resulted in duplicate stub output. Additionally, checking only the first buffer might be wrong in some unusual cases. For example, the first buffer might be empty if $r->flush() is called before printing any data in the embedded Perl module. Depending on the postpone_output value and corresponding sizes, this issue can result in either duplicate or unexpected stub output, or "zero size buf in writer" alerts. Following 8124:f5515e727656 (1.23.4), it became slightly easier to reproduce the issue, as empty static files and empty cache items now result in a response with an empty buffer. Before the change, an empty proxied response can be used to reproduce the issue. Fix is check all buffers and set r->request_output if any non-empty buffers are sent. This ensures that all unusual cases of non-empty responses are covered, and also that r->request_output will be set after the first stub output, preventing duplicate output. Reported by Jan Gassen.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 04 Jul 2024 17:41:28 +0300
parents ec2e6893caaa
children
line wrap: on
line source


# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


have=NGX_FREEBSD . auto/have_headers

CORE_INCS="$UNIX_INCS"
CORE_DEPS="$UNIX_DEPS $FREEBSD_DEPS"
CORE_SRCS="$UNIX_SRCS $FREEBSD_SRCS"

ngx_spacer='
'


# __FreeBSD_version and sysctl kern.osreldate are the best ways
# to determine whether some capability exists and is safe to use.
# __FreeBSD_version is used for the testing of the build environment.
# sysctl kern.osreldate is used for the testing of the kernel capabilities.

version=`grep "#define __FreeBSD_version" /usr/include/osreldate.h \
         | sed -e 's/^.* \(.*\)$/\1/'`

osreldate=`/sbin/sysctl -n kern.osreldate`


# setproctitle() in libutil

if [ \( $version -ge 500000 -a $version -lt 500012 \) \
     -o $version -lt 410002 ]
then
    echo " + setproctitle() in libutil"

    CORE_LIBS="$CORE_LIBS -lutil"
    NGX_SETPROCTITLE_LIB="-lutil"
fi

# sendfile

if [ $osreldate -gt 300007 ]; then
    echo " + sendfile() found"

    have=NGX_HAVE_SENDFILE . auto/have
    CORE_SRCS="$CORE_SRCS $FREEBSD_SENDFILE_SRCS"
fi

if [ $osreldate -gt 1100093 ]; then
    echo " + sendfile()'s SF_NODISKIO found"

    have=NGX_HAVE_SENDFILE_NODISKIO . auto/have
fi

# POSIX semaphores
# http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/127545

if [ $osreldate -ge 701106 ]; then
    echo " + POSIX semaphores should work"
else
    have=NGX_HAVE_POSIX_SEM . auto/nohave
fi


# kqueue

if [ \( $osreldate -lt 500000 -a $osreldate -ge 410000 \) \
     -o $osreldate -ge 500011 ]
then
    echo " + kqueue found"

    have=NGX_HAVE_KQUEUE . auto/have
    have=NGX_HAVE_CLEAR_EVENT . auto/have
    EVENT_MODULES="$EVENT_MODULES $KQUEUE_MODULE"
    CORE_SRCS="$CORE_SRCS $KQUEUE_SRCS"
    EVENT_FOUND=YES
fi


NGX_KQUEUE_CHECKED=YES


# kqueue's NOTE_LOWAT

if [ \( $version -lt 500000 -a $version -ge 430000 \) \
     -o $version -ge 500018 ]
then
    echo " + kqueue's NOTE_LOWAT found"
    have=NGX_HAVE_LOWAT_EVENT . auto/have
fi

# kqueue's EVFILT_TIMER

if [ \( $version -lt 500000 -a $version -ge 440001 \) \
     -o $version -ge 500023 ]
then
    echo " + kqueue's EVFILT_TIMER found"
    have=NGX_HAVE_TIMER_EVENT . auto/have
fi


# cpuset_setaffinity()

if [ $version -ge 701000 ]; then
    echo " + cpuset_setaffinity() found"
    have=NGX_HAVE_CPUSET_SETAFFINITY . auto/have
fi