#312314 w3m: "Absurd stack bottom value" error on a Grsecurity hardened system

Package:
libgc1c2
Source:
libgc
Submitter:
Martin-Éric Racine
Date:
2025-07-28 19:17:04 UTC
Severity:
normal
#312314#5
Date:
2005-06-07 10:44:15 UTC
From:
To:
<q-funk@omena:/home/q-funk>$ w3m http://www.debian.org
Absurd stack bottom value
Keskeytetty

Something in the compilation options make w3m request a stack value that grsecurity doesn't like, which prevents
someone from using w3m on a system with gersecurity-hardened kernel.

- -- System Information:
Debian Release: 3.1
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: powerpc (ppc)
Kernel: Linux 2.6.11-imac
Locale: LANG=fi_FI@euro, LC_CTYPE=fi_FI@euro (charmap=ISO-8859-15)

Versions of packages w3m depends on:
ii  libc6                    2.3.2.ds1-22    GNU C Library: Shared libraries an
ii  libgc1                   1:6.4-1         conservative garbage collector for
ii  libgpmg1                 1.19.6-19sarge1 General Purpose Mouse - shared lib
ii  libncurses5              5.4-4           Shared libraries for terminal hand
ii  libssl0.9.7              0.9.7e-3        SSL shared libraries
ii  zlib1g                   1:1.2.2-4       compression library - runtime

- -- no debconf information
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#312314#10
Date:
2006-07-24 12:25:07 UTC
From:
To:
It's not a problem with w3m, but rather with libgc.  Newer versions of
the garbage collector (6.3+ I think) try to determine the stack base
address by inspecting /proc/self/stat.  Unfortunately pax clears the
field that contains this address, so libgc gives up.

One workaround is to recompile libgc (version 6.7 is fine) with
-DUSE_LIBC_PRIVATES.  This tells the libaray to get the address
out of libc from the __libc_stack_end variable.  Linked to the
recompiled libgc, w3m works just as well as before.

bit,
adam
#312314#15
Date:
2008-06-23 12:06:42 UTC
From:
To:
reassign 312314 glibc
thanks

While triaging through my old bug submissions, I cam across this one
and found that the w3m issue I reported really is caused by glibc, so
I'm hereby reassigning this bug.

Meanwhile, if glibc has already been upgraded to do what the second
comment on this bug suggests, you are welcome to state so and close
this bug.

Best Regards,
#312314#28
Date:
2008-06-27 08:12:23 UTC
From:
To:
reassign 312314 libgc
thanks