some days ago while playing around with "ip neigh" a discovered a "flaw" when adding static arp entries with: $ ip neigh add 1.2.3.4 lladdr 01234 nud permanent dev lan0 the malformed macaddress 01234 results in segfault after showing the expected error message: "01234" is invalid lladdr. Segmentation fault. segfault is unexpected and can be reproduced on version ss130221 (gentoo) and ss120521 (debian). both with kernel 3.12.21 (which does not seem to matter). thanks a lot. --- execve("/bin/ip", ["ip", "neigh", "add", "1.2.3.4", "lladdr", "01234", "nud", "permanent", "dev", "lan0"], [/* 43 vars */]) = 0 brk(0) = 0xa001000 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb77c7000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3 fstat64(3, {st_mode=S_IFREG|0644, st_size=32014, ...}) = 0 mmap2(NULL, 32014, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb77bf000 close(3) = 0 open("/lib/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\200\f\0\0004\0\0\0"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=13724, ...}) = 0 mmap2(NULL, 16512, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb77ba000 mmap2(0xb77bd000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0xb77bd000 close(3) = 0 open("/lib/libc.so.6", O_RDONLY|O_CLOEXEC) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0@\320\1\0004\0\0\0"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=1738080, ...}) = 0 mmap2(NULL, 1747692, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb760f000 mmap2(0xb77b4000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1a5000) = 0xb77b4000 mmap2(0xb77b7000, 10988, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb77b7000 close(3) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb760e000 set_thread_area({entry_number:-1 -> 6, base_addr:0xb760e700, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}) = 0 mprotect(0xb77b4000, 8192, PROT_READ) = 0 mprotect(0xb77bd000, 4096, PROT_READ) = 0 mprotect(0x808d000, 4096, PROT_READ) = 0 mprotect(0xb77e9000, 4096, PROT_READ) = 0 munmap(0xb77bf000, 32014) = 0 socket(PF_NETLINK, SOCK_RAW, 0) = 3 setsockopt(3, SOL_SOCKET, SO_SNDBUF, [32768], 4) = 0 setsockopt(3, SOL_SOCKET, SO_RCVBUF, [1048576], 4) = 0 bind(3, {sa_family=AF_NETLINK, pid=0, groups=00000000}, 12) = 0 getsockname(3, {sa_family=AF_NETLINK, pid=599, groups=00000000}, [12]) = 0 time(NULL) = 1415815344 write(2, "\"01234\" is invalid lladdr.\n", 27"01234" is invalid lladdr. ) = 27 --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0xbf9be000} --- +++ killed by SIGSEGV +++ Segmentation fault Portage 2.2.8-r2 (default/linux/x86/13.0, gcc-4.7.3, glibc-2.19-r1, 3.12.21-jason-bare-i686-1403781919 i686) ================================================================= System uname: Linux-3.12.21-jason-bare-i686-1403781919-i686-Intel-R-_Xeon-R-_CPU_5160_@_3.00GHz-with-gentoo-2.2 KiB Mem: 3374184 total, 276448 free KiB Swap: 0 total, 0 free Timestamp of tree: Mon, 10 Nov 2014 09:00:01 +0000 ld GNU ld (Gentoo 2.24 p1.4) 2.24 app-shells/bash: 4.2_p53 dev-lang/perl: 5.18.2-r2 dev-lang/python: 2.7.7 dev-util/cmake: 2.8.12.2-r1 dev-util/pkgconfig: 0.28-r1 sys-apps/baselayout: 2.2 sys-apps/openrc: 0.12.4 sys-apps/sandbox: 2.6-r1 sys-devel/autoconf: 2.69 sys-devel/automake: 1.11.6, 1.12.6, 1.13.4 sys-devel/binutils: 2.24-r3 sys-devel/gcc: 4.7.3-r1 sys-devel/gcc-config: 1.7.3 sys-devel/libtool: 2.4.2-r1 sys-devel/make: 4.0-r1 sys-kernel/linux-headers: 3.13 (virtual/os-headers) sys-libs/glibc: 2.19-r1 Repositories: gentoo layer23 ACCEPT_KEYWORDS="x86" ACCEPT_LICENSE="* -@EULA" CBUILD="i686-pc-linux-gnu" CFLAGS="-O2 -march=i686 -fomit-frame-pointer -pipe" CHOST="i686-pc-linux-gnu" CONFIG_PROTECT="/etc /var/bind" CONFIG_PROTECT_MASK="/etc/* /etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/php/apache2-php5.5/ext-active/ /etc/php/cgi-php5.5/ext-active/ /etc/php/cli-php5.5/ext-active/ /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo" CXXFLAGS="-O2 -march=i686 -fomit-frame-pointer -pipe" DISTDIR="/tmp" FCFLAGS="-O2 -march=i686 -pipe" FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync" FFLAGS="-O2 -march=i686 -pipe" GENTOO_MIRRORS="http://distfiles.gentoo.org" LANG="C" LC_ALL="de_DE.UTF-8" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="-j5" PKGDIR="/tmp" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/var/portage" PORTDIR_OVERLAY="/dat/local/share/portage" USE="alsa berkdb bzip2 cli cxx dri fortran gd iconv imap jpeg mbox modules mysql ncurses nptl openmp pam pcre perl png readline sasl session ssl syslog tcpd tiff truetype unicode x86 xml zlib" ABI_X86="32" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1 emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="actions alias auth_basic auth_digest filter authn_default authn_file authz_default authz_groupfile authz_host authz_owner authz_user cgi deflate dumpio dav dav_fs dir env expires headers include info log_config mime mime_magic proxy proxy_balancer proxy_connect proxy_http rewrite setenvif so status userdir unique_id vhost_alias" APACHE2_MPMS="itk" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" 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 ublox ubx" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" NGINX_MODULES_HTTP="access auth_basic charset dav fastcgi gzip limit_req map proxy rewrite ssl stub_status" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-5" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7" QEMU_SOFTMMU_TARGETS="i386" RUBY_TARGETS="ruby19 ruby20" USERLAND="GNU" VIDEO_CARDS="fbdev glint intel mach64 mga nouveau nv r128 radeon savage sis tdfx trident vesa via vmware dummy v4l" 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, INSTALL_MASK, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, SYNC, USE_PYTHON
1) strace merely shows a write to stdout and then the segmentation fault. You really ought to attach a gdb backtrace instead. 2) Please post your `emerge -vpq sys-apps/iproute2' output in a comment.
