view auto/feature @ 7054:e02555553d0b

Range filter: protect from total size overflows. The overflow can be used to circumvent the restriction on total size of ranges introduced in c2a91088b0c0 (1.1.2). Additionally, overflow allows producing ranges with negative start (such ranges can be created by using a suffix, "bytes=-100"; normally this results in 200 due to the total size check). These can result in the following errors in logs: [crit] ... pread() ... failed (22: Invalid argument) [alert] ... sendfile() failed (22: Invalid argument) When using cache, it can be also used to reveal cache file header. It is believed that there are no other negative effects, at least with standard nginx modules. In theory, this can also result in memory disclosure and/or segmentation faults if multiple ranges are allowed, and the response is returned in a single in-memory buffer. This never happens with standard nginx modules though, as well as known 3rd party modules. Fix is to properly protect from possible overflow when incrementing size.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 11 Jul 2017 16:06:23 +0300
parents e3faa5fb7772
children
line wrap: on
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# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


echo $ngx_n "checking for $ngx_feature ...$ngx_c"

cat << END >> $NGX_AUTOCONF_ERR

----------------------------------------
checking for $ngx_feature

END

ngx_found=no

if test -n "$ngx_feature_name"; then
    ngx_have_feature=`echo $ngx_feature_name \
                   | tr abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ`
fi

if test -n "$ngx_feature_path"; then
    for ngx_temp in $ngx_feature_path; do
        ngx_feature_inc_path="$ngx_feature_inc_path -I $ngx_temp"
    done
fi

cat << END > $NGX_AUTOTEST.c

#include <sys/types.h>
$NGX_INCLUDE_UNISTD_H
$ngx_feature_incs

int main(void) {
    $ngx_feature_test;
    return 0;
}

END


ngx_test="$CC $CC_TEST_FLAGS $CC_AUX_FLAGS $ngx_feature_inc_path \
          -o $NGX_AUTOTEST $NGX_AUTOTEST.c $NGX_TEST_LD_OPT $ngx_feature_libs"

ngx_feature_inc_path=

eval "/bin/sh -c \"$ngx_test\" >> $NGX_AUTOCONF_ERR 2>&1"


if [ -x $NGX_AUTOTEST ]; then

    case "$ngx_feature_run" in

        yes)
            # /bin/sh is used to intercept "Killed" or "Abort trap" messages
            if /bin/sh -c $NGX_AUTOTEST >> $NGX_AUTOCONF_ERR 2>&1; then
                echo " found"
                ngx_found=yes

                if test -n "$ngx_feature_name"; then
                    have=$ngx_have_feature . auto/have
                fi

            else
                echo " found but is not working"
            fi
        ;;

        value)
            # /bin/sh is used to intercept "Killed" or "Abort trap" messages
            if /bin/sh -c $NGX_AUTOTEST >> $NGX_AUTOCONF_ERR 2>&1; then
                echo " found"
                ngx_found=yes

                cat << END >> $NGX_AUTO_CONFIG_H

#ifndef $ngx_feature_name
#define $ngx_feature_name  `$NGX_AUTOTEST`
#endif

END
            else
                echo " found but is not working"
            fi
        ;;

        bug)
            # /bin/sh is used to intercept "Killed" or "Abort trap" messages
            if /bin/sh -c $NGX_AUTOTEST >> $NGX_AUTOCONF_ERR 2>&1; then
                echo " not found"

            else
                echo " found"
                ngx_found=yes

                if test -n "$ngx_feature_name"; then
                    have=$ngx_have_feature . auto/have
                fi
            fi
        ;;

        *)
            echo " found"
            ngx_found=yes

            if test -n "$ngx_feature_name"; then
                have=$ngx_have_feature . auto/have
            fi
        ;;

    esac

else
    echo " not found"

    echo "----------"    >> $NGX_AUTOCONF_ERR
    cat $NGX_AUTOTEST.c  >> $NGX_AUTOCONF_ERR
    echo "----------"    >> $NGX_AUTOCONF_ERR
    echo $ngx_test       >> $NGX_AUTOCONF_ERR
    echo "----------"    >> $NGX_AUTOCONF_ERR
fi

rm -rf $NGX_AUTOTEST*