Bug 180680 – busybox & dash, read, and long lines

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Harald van Dijk (RETIRED) 2007-06-03 00:58:59 UTC]

dash does not appear to handle long lines well with read on amd64. In a 32-bit chroot, everything is fine.

$ cat bug.sh
(read line; echo "${line%%=*}") <<EOF
TITLE=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
EOF
printf "\
TITLE=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
" | (read line; echo "${line%%=*}")
$ bash bug.sh
TITLE
TITLE
$ dash bug.sh
TITLE=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
TITLE
$ emerge --info
Portage 2.1.2.9 (default-linux/amd64/2006.1/no-multilib, gcc-4.1.2, glibc-2.5-r3, 2.6.21-gentoo x86_64)
=================================================================
System uname: 2.6.21-gentoo x86_64 AMD Athlon(tm) 64 X2 Dual Core Processor 4200+
Gentoo Base System release 2.0.0_alpha3
Timestamp of tree: Sat, 02 Jun 2007 19:30:01 +0000
dev-java/java-config: 1.3.7, 2.0.33-r1
dev-lang/python:     2.4.4-r4
dev-python/pycrypto: 2.0.1-r5
sys-apps/sandbox:    1.2.18.1
sys-devel/autoconf:  2.13, 2.61
sys-devel/automake:  1.4_p6, 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r2, 1.10
sys-devel/binutils:  2.17
sys-devel/gcc-config: 1.4.0
sys-devel/libtool:   1.5.23b
virtual/os-headers:  2.6.21
ACCEPT_KEYWORDS="amd64 ~amd64"
AUTOCLEAN="yes"
CBUILD="x86_64-pc-linux-gnu"
CFLAGS="-march=athlon64 -O2 -pipe"
CHOST="x86_64-pc-linux-gnu"
CONFIG_PROTECT="/etc /usr/kde/3.5/env /usr/kde/3.5/share/config /usr/kde/3.5/shutdown /usr/share/X11/xkb /usr/share/config"
CONFIG_PROTECT_MASK="/etc/env.d /etc/env.d/java/ /etc/gconf /etc/revdep-rebuild /etc/terminfo /etc/texmf/web2c"
CXXFLAGS="-march=athlon64 -O2 -pipe"
DISTDIR="/usr/portage/distfiles"
EMERGE_DEFAULT_OPTS="--with-bdeps=y"
FEATURES="assume-digests collision-protect cvs distlocks metadata-transfer multilib-strict notitles parallel-fetch sandbox sfperms sign strict"
GENTOO_MIRRORS="http://distfiles.gentoo.org http://distro.ibiblio.org/pub/linux/distributions/gentoo"
LANG="en_GB.UTF-8"
LDFLAGS="-Xlinker --as-needed"
MAKEOPTS="-j2"
PKGDIR="/usr/portage/packages"
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --delete-after --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --filter=H_**/files/digest-*"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY="/var/cvs/gentoo-x86 /etc/portage/overlay /etc/portage/overlay/java-overlay /etc/portage/overlay/gcj-overlay"
SYNC="rsync://rsync.gentoo.org/gentoo-portage"
USE="X a52 akode alsa amd64 bidi bindist bitmap-fonts bzip2 cjk cli cracklib crypt cvs dri dvd dvdnav dvdread ffmpeg filepicker flac gcj gif gmp gtk iconv immqt ipv6 isdnlog jpeg kde kdeenablefinal kdehiddenvisibility libg++ mbox midi mozdevelop mudflap ncurses nls no-old-linux nocxx nptl nptlonly nsplugin ogg opengl pascal perl ppds pppd qt3 readline reflection rtc sdl session spl sql ssl tcpd threads truetype truetype-fonts type1-fonts unicode vorbis xcomposite xorg 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 mulaw multi null plug rate route share shm softvol" ELIBC="glibc" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" USERLAND="GNU" VIDEO_CARDS="nv vesa"
Unset:  CTARGET, INSTALL_MASK, LC_ALL, LINGUAS, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS

[Comment 1 Harald van Dijk (RETIRED) 2007-06-04 20:31:35 UTC]

Created attachment 121194 [details, diff]
patch

Here's a pretty obvious patch to fix this. It was just luck that it didn't occur for me on x86, and it was also just chance that I ran into it with read, it seems. I haven't sent this upstream (I don't even know where to go); would you do that, please?

[Comment 2 Harald van Dijk (RETIRED) 2007-06-04 20:33:36 UTC]

@embedded: you may be interested in this as well. busybox has the same problem, exposed by the same script, and the same patch (except to shells/ash.c) fixes it there too.

[Comment 3 Roy Marples (RETIRED) 2007-06-26 16:58:21 UTC]

Fixed in dash-0.5.3.8, thanks