Path: csiph.com!goblin1!goblin.stu.neva.ru!usenet.stanford.edu!not-for-mail
From: =?UTF-8?Q?kutay_=C3=BCner?= <husnukutay@gmail.com>
Newsgroups: gnu.bash.bug
Subject: SEGFAULT ON TILDE EXPANSION
Date: Fri, 10 Apr 2020 17:59:13 +0300
Lines: 31
Approved: bug-bash@gnu.org
Message-ID: <mailman.460.1586538065.2644.bug-bash@gnu.org>
References: <CAF8GSSDEdC-RUhT6iA34HixAZDHBZ0QTegAdPKPoGd+eZT_ZyA@mail.gmail.com>
NNTP-Posting-Host: lists.gnu.org
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
To: bug-bash@gnu.org
Envelope-to: bug-bash@gnu.org
Precedence: list
Xref: csiph.com gnu.bash.bug:16118

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -O0 -ggdb -Wno-parentheses -Wno-format-security
uname output: Linux hk 5.6.3-arch1-1 #9 SMP PREEMPT Thu, 09 Apr 2020
03:39:30 +0000 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu

Bash Version: 5.0
Patch Level: 16
Release Status: release

Description:
    Trying to tab expand a tilde causes segfault. This action requires us to
    get user entries by calling getpwent which is provided by
libnss_systemd.so
    on my system.
    If we compile bash with it's malloc implementation, libraries it depends
    on also start to use this version of malloc.
    getpwent function in libnss_systemd.so takes advantage of the C malloc
    returning max_align_t aligned memory. Bash malloc returns 8 byte
aligned
    memory which is less than 16 byte requirement on my x86-64 system. This
is the root cause of segfault.

Repeat-By:
$ echo ~u

Fix:
./configure --without-bash-malloc