Your message dated Wed, 3 Dec 2025 23:40:54 +0100
with message-id <[email protected]>
and subject line Re: Bug#1121758: dpkg-deb crashing on liblzma5
has caused the Debian Bug report #1121758,
regarding dpkg-deb crashing on liblzma5
to be marked as done.
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If this is not the case it is now your responsibility to reopen the
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--
1121758: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1121758
Debian Bug Tracking System
Contact [email protected] with problems
--- Begin Message ---
Package: liblzma5
Version: 5.8.1-2
Severity: serious
Hi,
see below for the stacktrace. This nonsense started a few days ago. The
system is perfectly stable otherwise, so I don't think this is a
hardware issue.
So I was trying to compile an upstream Linux kernel. Command, which has
been working for years, is:
$ nice -n20 make bindeb-pkg -j14 KCFLAGS='-march=x86-64-v3 -mtune=znver3'
And now it keeps segfaulting, like:
STRIP
debian/linux-image-6.18.0/lib/modules/6.18.0/kernel/virt/lib/irqbypass.ko
DEPMOD debian/linux-image-6.18.0/lib/modules/6.18.0
dpkg-deb: Paket »linux-image-6.18.0« wird in
»../linux-image-6.18.0_6.18.0-84_amd64.deb« gebaut.
dh_builddeb: error: dpkg-deb --root-owner-group --build
debian/linux-image-6.18.0 .. died with signal 13
dh_builddeb: error: Aborting due to earlier error
make[3]: *** [debian/rules:66: binary-image] Fehler 2
And why? The stacktrace from coredumpctl reveals:
#0 0x00007f4343d7b058 in bt_skip_func (len_limit=64, pos=8388609,
cur=cur@entry=0x7f4308379010 "\200\005", cur_match=253073, depth=47,
son=0x7f42fefbd010, cyclic_pos=0, cyclic_size=8388609)
at ../../../../src/liblzma/lz/lz_encoder_mf.c:546
warning: 546 ../../../../src/liblzma/lz/lz_encoder_mf.c: Datei oder
Verzeichnis nicht gefunden
[Current thread is 1 (Thread 0x7f4314e6f6c0 (LWP 3883979))]
(gdb) bt
#0 0x00007f4343d7b058 in bt_skip_func (len_limit=64, pos=8388609,
cur=cur@entry=0x7f4308379010 "\200\005", cur_match=253073, depth=47,
son=0x7f42fefbd010, cyclic_pos=0, cyclic_size=8388609)
at ../../../../src/liblzma/lz/lz_encoder_mf.c:546
#1 0x00007f4343d7bebe in lzma_mf_bt4_skip (mf=0x7f4304000c88, amount=1) at
../../../../src/liblzma/lz/lz_encoder_mf.c:740
#2 0x00007f4343d7cdef in mf_skip (mf=0x7f4304000c88, amount=1) at
../../../../src/liblzma/lz/lz_encoder.h:294
#3 encode_init (coder=0x7f433c4f9010, mf=0x7f4304000c88) at
../../../../src/liblzma/lzma/lzma_encoder.c:282
#4 lzma_lzma_encode (coder=0x7f433c4f9010, mf=mf@entry=0x7f4304000c88,
out=out@entry=0x7f4304000e06 "", out_pos=out_pos@entry=0x7f4304000df0,
out_size=out_size@entry=65536, limit=2096879)
at ../../../../src/liblzma/lzma/lzma_encoder.c:318
#5 0x00007f4343d845cd in lzma2_encode (coder_ptr=0x7f4304000d60,
mf=0x7f4304000c88, out=0x7f430a7fe050 "", out_pos=0x7f4314e6ee88,
out_size=25167072) at ../../../../src/liblzma/lzma/lzma2_encoder.c:188
#6 0x00007f4343d7a5c3 in lz_encode (coder_ptr=0x7f4304000c60, allocator=0x0,
in=0x7f4308ffd010 "\200\005", in_pos=0x7f4314e6ee90, in_size=16384,
out=0x7f430a7fe050 "", out_pos=0x7f4314e6ee88, out_size=25167072,
action=LZMA_RUN)
at ../../../../src/liblzma/lz/lz_encoder.c:176
#7 0x00007f4343d6e27c in block_encode (coder_ptr=0x7f4304000b70,
allocator=<optimized out>, in=0x7f4308ffd010 "\200\005", in_pos=0x7f4314e6ee90,
in_size=<optimized out>, out=0x7f430a7fe050 "", out_pos=0x7f4314e6ee88,
out_size=25167072,
action=LZMA_RUN) at ../../../../src/liblzma/common/block_encoder.c:63
#8 0x00007f4343d71907 in worker_encode (thr=0x55af3efeb580,
out_pos=0x7f4314e6ee88, state=<optimized out>) at
../../../../src/liblzma/common/stream_encoder_mt.c:294
#9 worker_start (thr_ptr=0x55af3efeb580) at
../../../../src/liblzma/common/stream_encoder_mt.c:393
#10 0x00007f4343b12b7b in start_thread (arg=<optimized out>) at
./nptl/pthread_create.c:448
#11 0x00007f4343b907b8 in __GI___clone3 () at
../sysdeps/unix/sysv/linux/x86_64/clone3.S:78
But why?
Okay, then I wanted to install one of my existing kernel-image DEBs. And then
initramfs build also started crashing.
But why? The common factor here was, again, liblzma5!
So I have changed the compression type of initramfs to zstd and now it works...
somehow. Still not explaining what is happening with liblzma5 here.
Best regards,
Eduard.
-- System Information:
Debian Release: forky/sid
APT prefers unstable-debug
APT policy: (500, 'unstable-debug'), (500, 'oldoldstable'), (500,
'unstable'), (500, 'testing'), (1, 'experimental-debug'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 6.18.0-rc5+ (SMP w/16 CPU threads; PREEMPT)
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled
Versions of packages dpkg depends on:
ii libbz2-1.0 1.0.8-6
ii libc6 2.41-12
ii liblzma5 5.8.1-2
ii libmd0 1.1.0-2+b1
ii libselinux1 3.9-2
ii libzstd1 1.5.7+dfsg-2
ii tar 1.35+dfsg-3.1
ii zlib1g 1:1.3.dfsg+really1.3.1-1+b1
dpkg recommends no packages.
Versions of packages dpkg suggests:
ii apt 3.1.12
pn debsig-verify <none>
-- no debconf information
--
Atheismus ist keine Philosophie, er ist noch nicht ein mal eine
Weltsicht. Er ist schlichtweg die Weigerung, ohne Grund das Gegenteil
des Offensichtlichen zu glauben.
--- End Message ---
--- Begin Message ---
Hallo,
* Guillem Jover [Wed, Dec 03 2025, 12:20:12PM]:
> > Okay, then I wanted to install one of my existing kernel-image DEBs. And
> > then initramfs build also started crashing.
> >
> > But why? The common factor here was, again, liblzma5!
> >
> > So I have changed the compression type of initramfs to zstd and now it
> > works... somehow. Still not explaining what is happening with liblzma5 here.
>
> I cannot reproduce this problem within liblzma5 (which would seem
> independent from dpkg, that has seen no upload since the release of
> Debian stable).
And this is the weird part which confuses me, this started happening
like out of blue. I have checked my RAM with memtest86, no issues were
found. ATM I start suspecting some influence from the CPU microcode. I
was using an RC kernel after all. But OTOH I have been using it for a
while, then again I have compiled it with CPU specific settings, but it
stitll was working fine, for a while.
But the last observation was that, for example:
make bindeb-pkg -j14 KCFLAGS='-march=x86-64-v3 -mtune=znver3' KDEB_COMPRESS=zstd
worked, but
make bindeb-pkg -j14 KCFLAGS='-march=x86-64-v3 -mtune=znver3' KDEB_COMPRESS=xz
simply failed with the mentioned symptoms.
> > Program received signal SIGPIPE, Broken pipe.
> > Download failed: Das Argument ist ungültig. Continuing without source file
> > ./nptl/./nptl/cancellation.c.
> > __internal_syscall_cancel (a1=a1@entry=6, a2=a2@entry=93824993085744,
> > a3=a3@entry=77, a4=a4@entry=0, a5=a5@entry=0, a6=a6@entry=0, nr=1) at
> > ./nptl/cancellation.c:44
> > warning: 44 ./nptl/cancellation.c: Datei oder Verzeichnis nicht gefunden
> > (gdb) bt
> > #0 __internal_syscall_cancel (a1=a1@entry=6, a2=a2@entry=93824993085744,
> > a3=a3@entry=77, a4=a4@entry=0, a5=a5@entry=0, a6=a6@entry=0, nr=1) at
> > ./nptl/cancellation.c:44
> > #1 0x00007ffff7cde6ad in __syscall_cancel (a1=a1@entry=6,
> > a2=a2@entry=93824993085744, a3=a3@entry=77, a4=a4@entry=0, a5=a5@entry=0,
> > a6=a6@entry=0, nr=1) at ./nptl/cancellation.c:75
> > #2 0x00007ffff7d53936 in __GI___libc_write (fd=fd@entry=6,
> > buf=buf@entry=0x555555624930, nbytes=nbytes@entry=77) at
> > ../sysdeps/unix/sysv/linux/write.c:26
> > #3 0x0000555555563389 in fd_write (fd=fd@entry=6,
> > buf=buf@entry=0x555555624930, len=77) at ../../../lib/dpkg/fdio.c:72
> > #4 0x000055555555a0a7 in file_treewalk_feed (dir=<optimized out>,
> > fd_out=6) at ../../src/deb/build.c:180
> > #5 0x0000555555559e87 in tarball_pack (dir=dir@entry=0x7fffffffe093
> > "debian/linux-image-6.18.0",
> > tar_filenames_feeder=tar_filenames_feeder@entry=0x55555555a040
> > <file_treewalk_feed>, options=options@entry=0x7fffffffd650,
> > tar_compress_params=0x555555580010 <compress_params>,
> > fd_out=fd_out@entry=4) at ../../src/deb/build.c:555
> > #6 0x000055555555a5c0 in do_build (argv=<optimized out>) at
> > ../../src/deb/build.c:730
> > #7 0x0000555555559adc in main (argc=<optimized out>, argv=<optimized out>)
> > at ../../src/deb/main.c:321
>
> And this looks like something else completely. Which I cannot
> reproduce either.
Yes, that is why I have been reluctant to report this. I just cannot
pinpoint this to an explicit culprit. My coredumpctl log shows a dozen
of crashes, all but one are from dpkg-deb.
The other coredump was from the call in initramfs, but I cannot reproduce it
today either.
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `/usr/bin/xz -6 --quiet --no-warn --no-adjust -T0'.
Program terminated with signal SIGSEGV, Segmentation fault.
Download failed: Das Argument ist ungültig. Continuing without source file
./debian/normal-build/src/liblzma/../../../../src/liblzma/lz/lz_encoder_mf.c.
#0 0x00007f4a85ccee4b in bt_find_func (len_limit=64, pos=8388612,
cur=0x7f4a80d79013 "ian/", cur_match=277094, depth=47, son=0x7f4a76fbd010,
cyclic_pos=3, cyclic_size=8388609, matches=0x7f4a85a822ec, len_best=3)
at ../../../../src/liblzma/lz/lz_encoder_mf.c:483
warning: 483 ../../../../src/liblzma/lz/lz_encoder_mf.c: Datei oder
Verzeichnis nicht gefunden
[Current thread is 1 (Thread 0x7f4a821fd6c0 (LWP 1137543))]
(gdb) bt
#0 0x00007f4a85ccee4b in bt_find_func (len_limit=64, pos=8388612,
cur=0x7f4a80d79013 "ian/", cur_match=277094, depth=47, son=0x7f4a76fbd010,
cyclic_pos=3, cyclic_size=8388609, matches=0x7f4a85a822ec, len_best=3)
at ../../../../src/liblzma/lz/lz_encoder_mf.c:483
#1 0x00007f4a85ccfc51 in lzma_mf_bt4_find (mf=0x7f4a7c000c88,
matches=0x7f4a85a822ec) at ../../../../src/liblzma/lz/lz_encoder_mf.c:721
#2 0x00007f4a85ccf1d7 in lzma_mf_find (mf=mf@entry=0x7f4a7c000c88,
count_ptr=count_ptr@entry=0x7f4a821fcbfc, matches=matches@entry=0x7f4a85a822ec)
at ../../../../src/liblzma/lz/lz_encoder_mf.c:27
#3 0x00007f4a85cd2b14 in helper1 (coder=0x7f4a85a82010, mf=0x7f4a7c000c88,
back_res=0x7f4a821fcc94, len_res=0x7f4a821fcc90, position=3) at
../../../../src/liblzma/lzma/lzma_encoder_optimum_normal.c:281
#4 lzma_lzma_optimum_normal (coder=coder@entry=0x7f4a85a82010,
mf=mf@entry=0x7f4a7c000c88, back_res=back_res@entry=0x7f4a821fcc94,
len_res=len_res@entry=0x7f4a821fcc90, position=3)
at ../../../../src/liblzma/lzma/lzma_encoder_optimum_normal.c:834
#5 0x00007f4a85cd12ac in lzma_lzma_encode (coder=0x7f4a85a82010,
mf=mf@entry=0x7f4a7c000c88, out=out@entry=0x7f4a7c000e06 "",
out_pos=out_pos@entry=0x7f4a7c000df0, out_size=out_size@entry=65536,
limit=2096879)
at ../../../../src/liblzma/lzma/lzma_encoder.c:376
#6 0x00007f4a85cd85cd in lzma2_encode (coder_ptr=0x7f4a7c000d60,
mf=0x7f4a7c000c88, out=0x7f4a839ff050 "", out_pos=0x7f4a821fce88,
out_size=25167072) at ../../../../src/liblzma/lzma/lzma2_encoder.c:188
#7 0x00007f4a85cce5c3 in lz_encode (coder_ptr=0x7f4a7c000c60, allocator=0x0,
in=0x7f4a821fe010 "debian/", in_pos=0x7f4a821fce90, in_size=16384,
out=0x7f4a839ff050 "", out_pos=0x7f4a821fce88, out_size=25167072,
action=LZMA_RUN)
at ../../../../src/liblzma/lz/lz_encoder.c:176
#8 0x00007f4a85cc227c in block_encode (coder_ptr=0x7f4a7c000b70,
allocator=<optimized out>, in=0x7f4a821fe010 "debian/", in_pos=0x7f4a821fce90,
in_size=<optimized out>, out=0x7f4a839ff050 "", out_pos=0x7f4a821fce88,
out_size=25167072,
action=LZMA_RUN) at ../../../../src/liblzma/common/block_encoder.c:63
#9 0x00007f4a85cc5907 in worker_encode (thr=0x55c6832e22d0,
out_pos=0x7f4a821fce88, state=<optimized out>) at
../../../../src/liblzma/common/stream_encoder_mt.c:294
#10 worker_start (thr_ptr=0x55c6832e22d0) at
../../../../src/liblzma/common/stream_encoder_mt.c:393
#11 0x00007f4a85b54b7b in start_thread (arg=<optimized out>) at
./nptl/pthread_create.c:448
#12 0x00007f4a85bd27b8 in __GI___clone3 () at
../sysdeps/unix/sysv/linux/x86_64/clone3.S:78
> > NOTE:
> >
> > I am also unable to use dpkg-source (as called from dpkg-build). Getting
> > a similar (same?) failure as with dpkg-deb in the debugger, i.e. not
> > SIGSEGV but SIGPIPE.
>
> If dpkg-source is also failing with SIGPIPE, then I'd say there's something
> going on in your environment.
Maybe, but I cannot pin-point it yet. Nothing from the crash dump looks
offending. But I have not been able to build Debian packages on this
system for some days while running the mentioned kernel, which was kinda
inconvenient.
> As it is I cannot reproduce neither of these issues, so there's not
> much that I can do here.
>
> (Also are you sure your system is good, f.ex. «dpkg -V»?)
I have run debsums already, nothing. "dpkg -V" shows missing files like
the stripped locale files, but nothing looks relevant.
dpkg -V | grep usr.lib
missing /usr/lib/python2.7/dist-packages/nevow/plugins
missing /usr/lib/python3.9
missing /usr/lib/i386-linux-gnu/gtk-3.0
missing /usr/lib/i386-linux-gnu/gtk-3.0/3.0.0
missing /usr/lib/i386-linux-gnu/gtk-2.0
missing /usr/lib/i386-linux-gnu/gtk-2.0/2.10.0
missing /usr/lib/gio
missing /usr/lib/gio/modules
missing /usr/lib/python2.7/dist-packages/axiom/plugins
missing /usr/lib/mesa-diverted
missing /usr/lib/mesa-diverted/i386-linux-gnu
missing /usr/lib/mesa-diverted/x86_64-linux-gnu
missing /usr/lib/libpython2.6_d.so.1.0-gdb.py
missing /usr/lib/python2.7/dist-packages/twisted/plugins
????????? /usr/lib/cups/backend/cups-brf
> So I tried to reproduce your original approach and didn't succeed. It
> built. So was the comptured thread the wrong one?
> Also you mentioned something about reproducing again while creating an
> initramfs. This was also dpkg related?
See above for the observations. I am not sure how to reproduce. Calling
the same command line as in the coredump in the plain environment seems
not to have any trouble.
But anyhow, I have upgraded the system further. The current kernel
6.18-rc7 from experimental, for example. Now the issue is not
reproducible anymore.
Best regards,
Eduard.
--- End Message ---
