The following program maps page 0x7fffffffe000 then use recv (translated into recvfrom in glibc) to receive 4096 bytes. according to strace's result, recvfrom returns -EFAULT. If change 0x7fffffffe000 to 0x7fffffffd000, recvfrom returns successfully. My kernel version is 2.6.36-gentoo-r5. #include <stdio.h> #include <stdlib.h> #include <memory.h> #include <sys/mman.h> #include <sys/socket.h> #include <assert.h> #define PAGE_SIZE (4096) #define LAST_PAGE ((void*)(0x7fffffffe000)) int main() { void * ptr = mmap(LAST_PAGE, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); assert(ptr == LAST_PAGE); memset(ptr, '\0', PAGE_SIZE); void * data = malloc(PAGE_SIZE); assert(data != NULL); memset(data, '1', PAGE_SIZE); int fds[2]; int err = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds); assert(err == 0); err = send(fds[0], data, PAGE_SIZE, 0); assert(err == PAGE_SIZE); err = recv(fds[1], ptr, PAGE_SIZE, MSG_WAITALL); perror("recv returns"); return 0; } // vim:ts=4:sw=4 Reproducible: Always Steps to Reproduce: 1. compile the program; 2. run the generated executable; Actual Results: recv returns: Bad address Expected Results: recv returns: Success
Please paste your `emerge --info' output in a comment.
Portage 2.1.9.25 (default/linux/amd64/10.0/desktop/gnome, gcc-4.4.4, glibc-2.11.2-r3, 2.6.36-gentoo-r5_work64 x86_64) ================================================================= System uname: Linux-2.6.36-gentoo-r5_work64-x86_64-Intel-R-_Core-TM-2_Duo_CPU_E4500_@_2.20GHz-with-gentoo-1.12.14 Timestamp of tree: Tue, 22 Feb 2011 00:45:01 +0000 ccache version 2.4 [enabled] app-shells/bash: 4.1_p9 dev-java/java-config: 2.1.11-r3 dev-lang/python: 2.6.6-r1, 3.1.2-r4 dev-util/ccache: 2.4-r9 dev-util/cmake: 2.8.1-r2 sys-apps/baselayout: 1.12.14-r1 sys-apps/sandbox: 2.4 sys-devel/autoconf: 2.13, 2.65-r1 sys-devel/automake: 1.9.6-r3, 1.10.3, 1.11.1 sys-devel/binutils: 2.20.1-r1 sys-devel/gcc: 4.4.4-r2 sys-devel/gcc-config: 1.4.1 sys-devel/libtool: 2.2.10 sys-devel/make: 3.81-r2 virtual/os-headers: 2.6.36.1 (sys-kernel/linux-headers) ACCEPT_KEYWORDS="amd64" ACCEPT_LICENSE="*" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-O2 -march=core2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/share/config /usr/share/gnupg/qualified.txt /var/lib/hsqldb" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/env.d/java/ /etc/eselect/postgresql /etc/fonts/fonts.conf /etc/gconf /etc/php/apache2-php5.3/ext-active/ /etc/php/cgi-php5.3/ext-active/ /etc/php/cli-php5.3/ext-active/ /etc/revdep-rebuild /etc/sandbox.d /etc/splash /etc/terminfo /etc/texmf/language.dat.d /etc/texmf/language.def.d /etc/texmf/updmap.d /etc/texmf/web2c" CXXFLAGS="-O2 -march=core2 -pipe" DISTDIR="/usr/portage/distfiles" FEATURES="assume-digests binpkg-logs ccache distlocks fixlafiles fixpackages news parallel-fetch protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch" GENTOO_MIRRORS="http://mirrors.sohu.com/gentoo/ rsync://mirrors.xmu.edu.cn/gentoo/" LANG="en_US.UTF-8" LDFLAGS="-Wl,-O1 -Wl,--as-needed" LINGUAS="zh_CN en_US" MAKEOPTS="-j3" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" SYNC="rsync://rsync2.cn.gentoo.org/gentoo-portage" USE="X a52 aac acl acpi alsa amd64 berkdb branding bzip2 cairo cdr cli consolekit cracklib crypt cups cxx dbus dri dts dvd dvdr eds emboss encode espeak evo exif fam fbcondecor festival firefox flac fontconfig fortran gdbm gdu gif gnome gnome-keyring gpm graphviz gstreamer gtk gucharmap hal iconv ipv6 java6 javascript jpeg lcms ldap libnotify lock mad mikmod mmx mng modules mp3 mp4 mpeg mudflap multilib nautilus ncurses nls nptl nptlonly nsplugin ogg opengl openmp pam pango pcre pdf perl png policykit ppds pppd pronounce python qqwry qt3support qt4 readline sdl session spell sql sqlite sse sse2 ssl start-notification startup-notification svg sysfs tcpd thunar tiff tk truetype udev unicode usb vorbis webkit x264 xcb xcomposite xft xml xorg xpm xulrunner xv xvid zlib" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mmap_emul mulaw multi null plug rate route share shm softvol" APACHE2_MODULES="actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ubx" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LINGUAS="zh_CN en_US" PHP_TARGETS="php5-3" RUBY_TARGETS="ruby18" USERLAND="GNU" VIDEO_CARDS="intel i810 vesa" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, FFLAGS, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, PORTDIR_OVERLAY
i doubt this is related to glibc. more likely a bug in the kernel in the address checking. really should be reported to bugzilla.kernel.org.
Also should be checked with an updated kernel
