GNU bug report logs - #29886
tests/rm/rm-readdir-fail is failing with SIGBUS on Gentoo sparc

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Thomas Deutschmann <whissi <at> gentoo.org>
To: bug-coreutils <at> gnu.org
Subject: tests/rm/rm-readdir-fail is failing with SIGBUS on Gentoo sparc
Date: Fri, 29 Dec 2017 03:39:47 +0100

Hi,

a Gentoo SPARC user is reporting that tests/rm/rm-readdir-fail is failing with SIGBUS
in coreutils-8.28 and coreutils-8.29:

> FAIL: tests/rm/rm-readdir-fail
> ==============================
> 
> ++ initial_cwd_=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29
> +++ testdir_prefix_
> +++ printf gt
> ++ pfx_=gt
> +++ mktempd_ /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29 gt-rm-readdir-fail.sh.XXXX
> +++ case $# in
> +++ destdir_=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29
> +++ template_=gt-rm-readdir-fail.sh.XXXX
> +++ MAX_TRIES_=4
> +++ case $destdir_ in
> +++ destdir_slash_=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/
> +++ case $template_ in
> ++++ unset TMPDIR
> +++ d=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> +++ case $d in
> +++ :
> +++ test -d /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> ++++ ls -dgo /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> +++ perms='drwx------ 2 4096 Dec 28 10:54 /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN'
> +++ case $perms in
> +++ :
> +++ echo /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> +++ return
> ++ test_dir_=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> ++ cd /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> ++ gl_init_sh_nl_='
> '
> ++ IFS=' 	
> '
> ++ for sig_ in 1 2 3 13 15
> +++ expr 1 + 128
> ++ eval 'trap '\''Exit 129'\'' 1'
> +++ trap 'Exit 129' 1
> ++ for sig_ in 1 2 3 13 15
> +++ expr 2 + 128
> ++ eval 'trap '\''Exit 130'\'' 2'
> +++ trap 'Exit 130' 2
> ++ for sig_ in 1 2 3 13 15
> +++ expr 3 + 128
> ++ eval 'trap '\''Exit 131'\'' 3'
> +++ trap 'Exit 131' 3
> ++ for sig_ in 1 2 3 13 15
> +++ expr 13 + 128
> ++ eval 'trap '\''Exit 141'\'' 13'
> +++ trap 'Exit 141' 13
> ++ for sig_ in 1 2 3 13 15
> +++ expr 15 + 128
> ++ eval 'trap '\''Exit 143'\'' 15'
> +++ trap 'Exit 143' 15
> ++ trap remove_tmp_ 0
> + path_prepend_ ./src
> + test 1 '!=' 0
> + path_dir_=./src
> + case $path_dir_ in
> + abs_path_dir_=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/./src
> + case $abs_path_dir_ in
> + PATH=/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/./src:/var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/src:/var/tmp/portage/sys-apps/coreutils-8.29/temp/mount-wrappers:/var/tmp/portage/sys-apps/coreutils-8.29/temp/python3.5/bin:/usr/lib/portage/python3.5/ebuild-helpers/xattr:/usr/lib/portage/python3.5/ebuild-helpers:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/sparc-unknown-linux-gnu/gcc-bin/6.4.0
> + create_exe_shims_ /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/./src
> + case $EXEEXT in
> + return 0
> + shift
> + test 0 '!=' 0
> + export PATH
> + print_ver_ rm
> + require_built_ rm
> + skip_=no
> + for i in '"$@"'
> + case " $built_programs " in
> + test no = yes
> + test yes = yes
> + local i
> + for i in '$*'
> + env rm --version
> rm (GNU coreutils) 8.29
> Packaged by Gentoo (8.29 (p1.0))
> Copyright (C) 2017 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.
> 
> Written by Paul Rubin, David MacKenzie, Richard M. Stallman,
> and Jim Meyering.
> + require_gcc_shared_
> + gcc_shared_ - d.so -xc
> + local in=-
> + local out=d.so
> + shift 2
> + sparc-unknown-linux-gnu-gcc -Wall -shared --std=gnu99 -fPIC -O2 -xc - -o d.so -ldl
> + rm -f d.so
> + mkdir -p dir/notempty
> + cat
> + gcc_shared_ k.c k.so
> + local in=k.c
> + local out=k.so
> + shift 2
> + sparc-unknown-linux-gnu-gcc -Wall -shared --std=gnu99 -fPIC -O2 k.c -o k.so -ldl
> + export READDIR_PARTIAL
> + for READDIR_PARTIAL in ''\'''\''' ''\''1'\'''
> + rm -f preloaded
> + export LD_PRELOAD=libsandbox.so:./k.so
> + LD_PRELOAD=libsandbox.so:./k.so
> + returns_ 1 rm -Rf dir
> + test -f preloaded
> + for READDIR_PARTIAL in ''\'''\''' ''\''1'\'''
> + rm -f preloaded
> + export LD_PRELOAD=libsandbox.so:./k.so
> + LD_PRELOAD=libsandbox.so:./k.so
> + returns_ 1 rm -Rf dir
> + fail=1
> + test -f preloaded
> + cat
> + sed 's/\(rm:.*\):.*/\1/' errt
> + compare exp err
> + compare_dev_null_ exp err
> + test 2 = 2
> + test xexp = x/dev/null
> + test xerr = x/dev/null
> + return 2
> + case $? in
> + compare_ exp err
> + diff -u exp err
> --- exp	2017-12-28 10:54:33.403337960 +0100
> +++ err	2017-12-28 10:54:33.423337960 +0100
> @@ -1,2 +1,2 @@
>  rm: cannot remove 'dir'
> -rm: traversal failed: dir
> +./tests/init.sh: line 118:  9012 Bus error               "$@"
> + fail=1
> + Exit 1
> + set +e
> + exit 1
> + exit 1
> + remove_tmp_
> + __st=1
> + cleanup_
> + :
> + test '' = yes
> + cd /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29
> + chmod -R u+rwx /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> + rm -rf /var/tmp/portage/sys-apps/coreutils-8.29/work/coreutils-8.29/gt-rm-readdir-fail.sh.ZZkN
> + exit 1
> FAIL tests/rm/rm-readdir-fail.sh (exit status: 1)

System details:

> Portage 2.3.13 (python 3.5.4-final-0, default/linux/sparc/17.0, gcc-6.4.0, glibc-2.25-r9, 4.14.8-gentoo-r1 sparc64)
> =================================================================
>                          System Settings
> =================================================================
> System uname: Linux-4.14.8-gentoo-r1-sparc64-sun4v-with-gentoo-2.3
> KiB Mem:    33133552 total,  21139472 free
> KiB Swap:          0 total,         0 free
> Timestamp of repository gentoo: Thu, 28 Dec 2017 01:15:01 +0000
> Head commit of repository gentoo: dbbcaa80af14ec02c8eba29c56f946886b192845
> sh bash 4.3_p48-r1
> ld GNU ld (Gentoo 2.29.1 p3) 2.29.1
> app-shells/bash:          4.3_p48-r1::gentoo
> dev-lang/perl:            5.24.3::gentoo
> dev-lang/python:          2.7.14-r1::gentoo, 3.4.5::gentoo, 3.5.4-r1::gentoo
> dev-util/cmake:           3.8.2::gentoo
> dev-util/pkgconfig:       0.29.2::gentoo
> sys-apps/baselayout:      2.3::gentoo
> sys-apps/openrc:          0.34.11::gentoo
> sys-apps/sandbox:         2.10-r4::gentoo
> sys-devel/autoconf:       2.69::gentoo
> sys-devel/automake:       1.15.1-r1::gentoo
> sys-devel/binutils:       2.29.1-r1::gentoo
> sys-devel/gcc:            6.4.0::gentoo
> sys-devel/gcc-config:     1.8-r1::gentoo
> sys-devel/libtool:        2.4.6-r3::gentoo
> sys-devel/make:           4.2.1::gentoo
> sys-kernel/linux-headers: 4.4::gentoo (virtual/os-headers)
> sys-libs/glibc:           2.25-r9::gentoo

Bug: https://bugs.gentoo.org/642492


-- 
Regards,
Thomas Deutschmann / Gentoo Linux Developer
C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5

Message #8 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Thomas Deutschmann <whissi <at> gentoo.org>
To: bug-coreutils <at> gnu.org
Subject: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on Gentoo
 sparc
Date: Tue, 10 Jul 2018 00:26:13 +0200

Hi,

still happening with coreutils-8.30.


-- 
Regards,
Thomas Deutschmann / Gentoo Linux Developer
C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5

Message #11 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Thomas Deutschmann <whissi <at> gentoo.org>
To: bug-coreutils <at> gnu.org
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Tue, 10 Jul 2018 23:46:25 +0200

[Message part 1 (text/plain, inline)]

Hi,

a Gentoo sparc user proposed the following fix:

From: Rolf Eike Beer <eike <at> sf-mail.de>
Date: Tue, 10 Jul 2018 20:14:18 +0200
Subject: [PATCH] fix SIGBUS because of unaligned access in rm

This crashes the rm-readdir-fail test on Gentoo Sparc.

Bug: https://bugs.gentoo.org/642492

--- a/lib/fts.c	2018-06-24 06:52:06.000000000 +0200
+++ b/lib/fts.c	2018-07-10 14:08:32.382614958 +0200
@@ -1551,7 +1551,7 @@ mem1:                           saved_er
 
                 /* Store dirent.d_ino, in case we need to sort
                    entries before processing them.  */
-                p->fts_statp->st_ino = D_INO (dp);
+                memcpy(&p->fts_statp->st_ino, &dp, sizeof(p->fts_statp->st_ino));
 
                 /* Build a file name for fts_stat to stat. */
                 if (ISSET(FTS_NOCHDIR)) {



-- 
Regards,
Thomas Deutschmann / Gentoo Linux Developer
C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5

[signature.asc (application/pgp-signature, attachment)]

Message #14 received at 29886 <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Thomas Deutschmann <whissi <at> gentoo.org>, 29886 <at> debbugs.gnu.org
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Tue, 10 Jul 2018 19:46:16 -0700

Thomas Deutschmann wrote:
> -                p->fts_statp->st_ino = D_INO (dp);
> +                memcpy(&p->fts_statp->st_ino, &dp, sizeof(p->fts_statp->st_ino));

This looks like a kernel bug, not a coreutils bug. readdir must be returning a 
pointer to an misaligned struct. Can you look into that? For example, what 
happens if you insert this:

  if ((intptr_t) (dp) % _Alignof (struct dirent) != 0)
     abort ();

before the memcpy? The 'abort ()' should never happen; if it does, there's a bug 
in readdir, surely.

Message #17 received at 29886 <at> debbugs.gnu.org (full text, mbox):

From: Thomas Deutschmann <whissi <at> gentoo.org>
To: Paul Eggert <eggert <at> cs.ucla.edu>, 29886 <at> debbugs.gnu.org
Subject: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on Gentoo
 sparc
Date: Wed, 11 Jul 2018 18:53:40 +0200

[Message part 1 (text/plain, inline)]

On 2018-07-11 04:46, Paul Eggert wrote:
> Thomas Deutschmann wrote:
>> -                p->fts_statp->st_ino = D_INO (dp);
>> +                memcpy(&p->fts_statp->st_ino, &dp,
>> sizeof(p->fts_statp->st_ino));
> 
> This looks like a kernel bug, not a coreutils bug. readdir must be
> returning a pointer to an misaligned struct. Can you look into that? For
> example, what happens if you insert this:
> 
>   if ((intptr_t) (dp) % _Alignof (struct dirent) != 0)
>      abort ();
> 
> before the memcpy? The 'abort ()' should never happen; if it does,
> there's a bug in readdir, surely.

Not sure if this is a kernel problem. Isn't test suite using
LD_PRELOAD to pull in additional libraries which could cause
such a breakage? And wouldn't "rm" show any failure during normal
use?

The sparc user added the requested debug code and confirmed that
abort() will be triggered.

#0  0xf7e230fc in raise () from /lib/libc.so.6
#1  0xf7e25240 in abort () from /lib/libc.so.6
#2  0x0001813c in fts_build (sp=sp <at> entry=0x309c0, type=type <at> entry=3) at lib/fts.c:1555
#3  0x00018bd0 in fts_read (sp=sp <at> entry=0x309c0) at lib/fts.c:966
#4  0x00012750 in rm (file=file <at> entry=0xffffc95c, x=x <at> entry=0xffffc7f4) at src/remove.c:596
#5  0x00011564 in main (argc=<optimized out>, argv=<optimized out>) at src/rm.c:370
(gdb) frame 2
(gdb) p dp
$1 = (struct dirent *) 0x31dcc

User said it is also always going through

#0  0xf7fb4684 in readdir64 () from ./k.so

Kernel: Linux castor 4.16.8 #1 SMP Tue May 15 22:40:58 CEST 2018 sparc64 sun4v UltraSparc T2 (Niagara2) GNU/Linux


-- 
Regards,
Thomas Deutschmann / Gentoo Linux Developer
C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5

[signature.asc (application/pgp-signature, attachment)]

Message #20 received at 29886 <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Thomas Deutschmann <whissi <at> gentoo.org>, 29886 <at> debbugs.gnu.org
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Wed, 11 Jul 2018 10:05:59 -0700

[Message part 1 (text/plain, inline)]

Thomas Deutschmann wrote:

> Not sure if this is a kernel problem. Isn't test suite using
> LD_PRELOAD to pull in additional libraries which could cause
> such a breakage?

You're right, it could be a library problem. The test suite's LD_PRELOAD library 
just returns what the C library gives it, though. Perhaps LD_PRELOAD usage is 
messing up malloc on your platform, so that it returns improperly-aligned 
pointers? You might try something like the attached patch to see whether the C 
library is doing that.

> And wouldn't "rm" show any failure during normal use?

Yes, one would think so.

In any case, this is not sounding like a bug in coreutils itself.

[diff (text/plain, attachment)]

Message #23 received at 29886 <at> debbugs.gnu.org (full text, mbox):

From: Thomas Deutschmann <whissi <at> gentoo.org>
To: Paul Eggert <eggert <at> cs.ucla.edu>, 29886 <at> debbugs.gnu.org,
 Rolf Eike Beer <eike <at> sf-mail.de>
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Wed, 11 Jul 2018 19:30:57 +0200

[Message part 1 (text/plain, inline)]

On 2018-07-11 19:05, Paul Eggert wrote:
> Thomas Deutschmann wrote:
> 
>> Not sure if this is a kernel problem. Isn't test suite using
>> LD_PRELOAD to pull in additional libraries which could cause
>> such a breakage?
> 
> You're right, it could be a library problem. The test suite's LD_PRELOAD
> library just returns what the C library gives it, though. Perhaps
> LD_PRELOAD usage is messing up malloc on your platform, so that it
> returns improperly-aligned pointers? You might try something like the
> attached patch to see whether the C library is doing that.

Looks like we are on the right track, with your diff:

#0  0xf7e230fc in raise () from /lib/libc.so.6
#1  0xf7e25240 in abort () from /lib/libc.so.6
#2  0xf7fb4840 in readdir64 () from ./k.so


Adding Rolf (the Gentoo sparc user) to this mail conversation.


-- 
Regards,
Thomas Deutschmann / Gentoo Linux Developer
C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5

[signature.asc (application/pgp-signature, attachment)]

Message #26 received at 29886 <at> debbugs.gnu.org (full text, mbox):

From: Pádraig Brady <P <at> draigBrady.com>
To: Paul Eggert <eggert <at> cs.ucla.edu>, Thomas Deutschmann <whissi <at> gentoo.org>, 
 29886 <at> debbugs.gnu.org
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Sat, 14 Jul 2018 18:21:12 -0700

On 11/07/18 10:05, Paul Eggert wrote:
> Thomas Deutschmann wrote:
> 
>> Not sure if this is a kernel problem. Isn't test suite using
>> LD_PRELOAD to pull in additional libraries which could cause
>> such a breakage?
> 
> You're right, it could be a library problem. The test suite's LD_PRELOAD library 
> just returns what the C library gives it, though. Perhaps LD_PRELOAD usage is 
> messing up malloc on your platform, so that it returns improperly-aligned 
> pointers? You might try something like the attached patch to see whether the C 
> library is doing that.
> 
>> And wouldn't "rm" show any failure during normal use?
> 
> Yes, one would think so.
> 
> In any case, this is not sounding like a bug in coreutils itself.

This could be due to my hack for 32 bit in:
https://git.sv.gnu.org/cgit/coreutils.git/commit/?id=v8.25-43-g54c1397
which fails due to the alignment requirement on sparc

This is using a 32 bit userland right?

We can skip this test on 32 bit, as there really
is nothing arch specific that we're testing here.

Does this skip the test for you?

diff --git a/tests/rm/rm-readdir-fail.sh b/tests/rm/rm-readdir-fail.sh
index 75fa339..580d8ec 100755
--- a/tests/rm/rm-readdir-fail.sh
+++ b/tests/rm/rm-readdir-fail.sh
@@ -27,9 +27,9 @@ mkdir -p dir/notempty || framework_failure_
 cat > k.c <<\EOF || framework_failure_
 #define _GNU_SOURCE

-/* Setup so we don't have to worry about readdir64.  */
+/* Avoid having to also handle readdir64.  */
 #ifndef __LP64__
-# define _FILE_OFFSET_BITS 64
+# error skipping test on 32 bit
 #endif

 #include <dlfcn.h>

Message #29 received at 29886 <at> debbugs.gnu.org (full text, mbox):

From: Thomas Deutschmann <whissi <at> gentoo.org>
To: Pádraig Brady <P <at> draigBrady.com>,
 Paul Eggert <eggert <at> cs.ucla.edu>, 29886 <at> debbugs.gnu.org,
 Rolf Eike Beer <eike <at> sf-mail.de>
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Sun, 15 Jul 2018 16:28:53 +0200

On 2018-07-15 03:21, Pádraig Brady wrote:
> Does this skip the test for you?

No, it doesn't:

chroot /var/tmp/portage/sys-apps/coreutils-8.30/work/coreutils-8.30 # make 
check TESTS=tests/rm/rm-readdir-fail.sh
if test -d ./.git                               \
        && git --version >/dev/null 2>&1; then                  \
  cd . &&                                               \
  git submodule --quiet foreach                                 \
      'test "$(git rev-parse "$sha1")"                  \
          = "$(git merge-base origin "$sha1")"'         \
    || { echo 'maint.mk: found non-public submodule commit' >&2;        \
         exit 1; };                                             \
else                                                            \
  : ;                                                           \
fi
make  check-recursive
make[1]: Entering directory '/var/tmp/portage/sys-apps/coreutils-8.30/work/
coreutils-8.30'
Making check in po
make[2]: Entering directory '/var/tmp/portage/sys-apps/coreutils-8.30/work/
coreutils-8.30/po'
make[2]: Nothing to be done for 'check'.
make[2]: Leaving directory '/var/tmp/portage/sys-apps/coreutils-8.30/work/
coreutils-8.30/po'
Making check in .
make[2]: Entering directory '/var/tmp/portage/sys-apps/coreutils-8.30/work/
coreutils-8.30'
make  check-TESTS check-local
make[3]: Entering directory '/var/tmp/portage/sys-apps/coreutils-8.30/work/
coreutils-8.30'
make[4]: Entering directory '/var/tmp/portage/sys-apps/coreutils-8.30/work/
coreutils-8.30'
rm-readdir-fail.sh: set-up failure: failed to build shared library
ERROR: tests/rm/rm-readdir-fail.sh
[...]


-- 
Regards,
Thomas Deutschmann / Gentoo Linux Developer
C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5

Message #34 received at 29886-done <at> debbugs.gnu.org (full text, mbox):

From: Pádraig Brady <P <at> draigBrady.com>
To: Thomas Deutschmann <whissi <at> gentoo.org>, Paul Eggert <eggert <at> cs.ucla.edu>, 
 29886-done <at> debbugs.gnu.org, Rolf Eike Beer <eike <at> sf-mail.de>
Subject: Re: bug#29886: tests/rm/rm-readdir-fail is failing with SIGBUS on
 Gentoo sparc
Date: Sun, 15 Jul 2018 11:02:09 -0700

[Message part 1 (text/plain, inline)]

On 15/07/18 07:28, Thomas Deutschmann wrote:
> On 2018-07-15 03:21, Pádraig Brady wrote:
>> Does this skip the test for you?

> rm-readdir-fail.sh: set-up failure: failed to build shared library
> ERROR: tests/rm/rm-readdir-fail.sh

Thanks for confirming your __LP64__ setting.
I'm going to go with the attached.

thanks,
Pádraig.

[rm-sparc-test.patch (text/x-patch, attachment)]

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