pp_sys.c:957: Perl_pp_tie: Assertion `!isGV_with_GP(_svcur)' failed

[p5pRT]

Migrated from rt.perl.org#130623 (status was 'resolved')

Searchable as RT130623$

[p5pRT]

From @dur-randir

Created by @dur-randir

While fuzzing perl v5.25.8-216-gfbceb79751 built with afl and run
under libdislocator, I found the following program

tie$0,*0

to cause an assertion failure. This is a regression in blead, bisect points to

0b077c8 is the first bad commit
commit 0b077c8
Author​: Dagfinn Ilmari Mannsåker <ilmari@​ilmari.org>
Date​: Sun Nov 13 15​:10​:38 2016 +0100

  Improve error for missing tie() pacakge/method

  This brings the error messages in line with the ones used for normal
  method calls, despite not using call_method().

GDB info about the crash location​:

(gdb) bt
#0 __GI_raise (sig=sig@​entry=6) at ../sysdeps/unix/sysv/linux/raise.c​:58
#1 0x00007f869ed7f40a in __GI_abort () at abort.c​:89
#2 0x00007f869ed76e47 in __assert_fail_base (fmt=<optimized out>,
assertion=assertion@​entry=0x7f86a04924f6 "!isGV_with_GP(_svcur)",
  file=file@​entry=0x7f86a049245f "pp_sys.c", line=line@​entry=957,
function=function@​entry=0x7f86a0494a80 <__PRETTY_FUNCTION__.15407>
"Perl_pp_tie")
  at assert.c​:92
#3 0x00007f869ed76ef2 in __GI___assert_fail (assertion=0x7f86a04924f6
"!isGV_with_GP(_svcur)", file=0x7f86a049245f "pp_sys.c", line=957,
  function=0x7f86a0494a80 <__PRETTY_FUNCTION__.15407> "Perl_pp_tie")
at assert.c​:101
#4 0x00007f86a033e545 in Perl_pp_tie () at pp_sys.c​:957
#5 0x00007f86a0200bde in Perl_runops_debug () at dump.c​:2260
#6 0x00007f86a00fb156 in S_run_body (oldscope=1) at perl.c​:2528
#7 0x00007f86a00fa6d4 in perl_run (my_perl=0x7f86a1732010) at perl.c​:2451
#8 0x00007f86a00b5d3e in main (argc=2, argv=0x7fff65409c28,
env=0x7fff65409c40) at perlmain.c​:123

Perl Info

Flags:
    category=core
    severity=medium

Site configuration information for perl 5.25.9:

Configured by root at Sat Jan 14 02:25:05 MSK 2017.

Summary of my perl5 (revision 5 version 25 subversion 9) configuration:
  Commit id: cbe2fc5001aa59cdc73e04cc35e097a2ecfbeec0
  Platform:
    osname=linux
    osvers=3.16.0-4-amd64
    archname=x86_64-linux
    uname='linux dorothy 3.16.0-4-amd64 #1 smp debian 3.16.36-1+deb8u2
(2016-10-19) x86_64 gnulinux '
    config_args='-des -Dusedevel -DDEBUGGING -Dcc=afl-clang-fast
-Doptimize=-O0 -g -ggdb3'
    hint=recommended
    useposix=true
    d_sigaction=define
    useithreads=undef
    usemultiplicity=undef
    use64bitint=define
    use64bitall=define
    uselongdouble=undef
    usemymalloc=n
    bincompat5005=undef
  Compiler:
    cc='afl-clang-fast'
    ccflags ='-DDEBUGGING -fno-strict-aliasing -pipe
-fstack-protector-strong -I/usr/local/include -D_LARGEFILE_SOURCE
-D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2'
    optimize='-O0 -g -ggdb3'
    cppflags='-DDEBUGGING -fno-strict-aliasing -pipe
-fstack-protector-strong -I/usr/local/include'
    ccversion=''
    gccversion='4.2.1 Compatible Clang 3.9.1 (tags/RELEASE_391/rc2)'
    gccosandvers=''
    intsize=4
    longsize=8
    ptrsize=8
    doublesize=8
    byteorder=12345678
    doublekind=3
    d_longlong=define
    longlongsize=8
    d_longdbl=define
    longdblsize=16
    longdblkind=3
    ivtype='long'
    ivsize=8
    nvtype='double'
    nvsize=8
    Off_t='off_t'
    lseeksize=8
    alignbytes=8
    prototype=define
  Linker and Libraries:
    ld='afl-clang-fast'
    ldflags =' -fstack-protector-strong -L/usr/local/lib'
    libpth=/usr/local/lib /usr/lib/llvm-3.9/bin/../lib/clang/3.9.1/lib
/usr/include/x86_64-linux-gnu /usr/lib /lib/x86_64-linux-gnu
/lib/../lib /usr/lib/x86_64-linux-gnu /usr/lib/../lib /lib
    libs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    perllibs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    libc=libc-2.24.so
    so=so
    useshrplib=false
    libperl=libperl.a
    gnulibc_version='2.24'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs
    dlext=so
    d_dlsymun=undef
    ccdlflags='-Wl,-E'
    cccdlflags='-fPIC'
    lddlflags='-shared -O0 -g -ggdb3 -L/usr/local/lib -fstack-protector-strong'



@INC for perl 5.25.9:
    lib
    /usr/local/lib/perl5/site_perl/5.25.9/x86_64-linux
    /usr/local/lib/perl5/site_perl/5.25.9
    /usr/local/lib/perl5/5.25.9/x86_64-linux
    /usr/local/lib/perl5/5.25.9


Environment for perl 5.25.9:
    HOME=/home/afl
    LANG=en_US.UTF-8
    LANGUAGE=en_US:en
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/afl/perlbrew/bin:/home/afl/perlbrew/perls/perl-5.22.1/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
    PERLBREW_BASHRC_VERSION=0.78
    PERLBREW_HOME=/home/afl/.perlbrew
    PERLBREW_MANPATH=/home/afl/perlbrew/perls/perl-5.22.1/man
    PERLBREW_PATH=/home/afl/perlbrew/bin:/home/afl/perlbrew/perls/perl-5.22.1/bin
    PERLBREW_PERL=perl-5.22.1
    PERLBREW_ROOT=/home/afl/perlbrew
    PERLBREW_VERSION=0.78
    PERL_BADLANG (unset)
    SHELL=/usr/bin/zsh

[p5pRT]

From @dur-randir

Different way to hit the same line, but with another assertion​:

tie%0,\0

pp_sys.c​:957​: OP *Perl_pp_tie()​: Assertion `PL_valid_types_PVX[SvTYPE(_svcur) & SVt_MASK] || SvTYPE(_svcur) == SVt_REGEXP' failed.

[p5pRT]

From [Unknown Contact. See original ticket]

Different way to hit the same line, but with another assertion​:

tie%0,\0

pp_sys.c​:957​: OP *Perl_pp_tie()​: Assertion `PL_valid_types_PVX[SvTYPE(_svcur) & SVt_MASK] || SvTYPE(_svcur) == SVt_REGEXP' failed.

[p5pRT]

From @arc

Thanks for the report. As you surmise, these are subtly different bugs relating to the same area of code. They are fixed as of 32207c6.

--
Aaron Crane ** http​://aaroncrane.co.uk/

[p5pRT]

The RT System itself - Status changed from 'new' to 'open'

[p5pRT]

@arc - Status changed from 'open' to 'resolved'