aurman fails to run on Raspberry Pi 2

[hansheijmans]

Description

I wanted to update my Archlinux on my Raspberry Pi 2 like I used to do every one or two weeks. After the latest update using aurman (in which aurman itself was updated also from 2.14 to 2.16) I ran into this issue. Apparently this issue only appears on my Raspberry Pi 2 armv7h platform. On x86_64 the error did not appear.

Expected Behavior

aurman --version should return 2.16-1 or anything similar

Current Behavior

This is what I got:

2018-07-04 23:10:34,521 - wrappers - expac - ERROR - expac query -Q %v - for targets ['aurman-git', 'aurman'] failed
2018-07-04 23:10:34,523 - main - main - ERROR - 
Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/aurman/main.py", line 835, in main
    process(argv[1:])
  File "/usr/lib/python3.6/site-packages/aurman/main.py", line 345, in process
    show_version()
  File "/usr/lib/python3.6/site-packages/aurman/main.py", line 85, in show_version
    aurman_note(expac("-Q", ["v"], ["aurman-git", "aurman"])[0])
  File "/usr/lib/python3.6/site-packages/aurman/wrappers.py", line 69, in expac
    raise InvalidInput("expac query {} for targets {} failed".format(query_stringified, targets))
aurman.own_exceptions.InvalidInput: expac query -Q %v - for targets ['aurman-git', 'aurman'] failed

Possible Solution

Sorry, I wouldn't know, seems related to platform.

Version of aurman you are using

Latest package on AUR (2.16-1)

Steps to Reproduce

1. aurman --version or -V
2. Also tried aurman -Syu with similar result:

2018-07-04 23:20:40,564 - wrappers - expac - ERROR - expac query -Q '%n?!%v?!%D?!%H?!%o?!%P?!%T?!%e?!%G?!%w' - for targets ['faad2', 'bash', ...........] failed

3. Tried updating expac-git manually from AUR --> no change in behaviour
4. Tried replacing expac-git by expac from stable --> no change in behaviour

Read the README

Yes, I did!

Running linux distribution

Linux RPIarch 4.14.52-1-ARCH #1 SMP Thu Jun 28 00:45:47 UTC 2018 armv7l GNU/Linux

[polygamma]

What is the output of this printf "%s\n" aurman aurman-git expac expac-git | expac -Q "%n %v" - command? Do not miss the - at the end of the command.

[hansheijmans]

@polygamma ,
error: buffer overflow on stdin
both as regular user and as root
Typo?

[polygamma]

Nope, definitely not a typo, seems to be a problem with Arch Linux ARM. I am not sure if I am able to help you, to be honest, maybe @eli-schwartz, @AladW or @Morganamilo know something about this?

I can say for sure, that it has something to do with how expac is being called since aurman 2.16, see b56691d#diff-1d9d6ff44724af9296e5dec4a6802a28R61 and the relevant discussion here: #171 (diff)

I am going to investigate, but I am not very confident that I am able to say what the real problem is, since I am not using Arch Linux ARM. Btw. for reference, when I run the command:

[jonny@jonny-arch-pc ~]$ printf "%s\n" aurman aurman-git expac expac-git | expac -Q "%n %v" -
aurman-git 2.16.r6.g8da4f35-1
expac 9-1

[polygamma]

Addition: The error message comes from here: https://github.com/falconindy/expac/blob/master/expac.c#L822

[hansheijmans]

@polygamma , thanks for your time! Will keep monitoring this thread.

[polygamma]

@hansheijmans

please paste the following into a file called test.c:

#include <stdio.h>

int main() {
    printf("BUFSIZ: %d\n", BUFSIZ);
    return 0;
}

go with cd into that folder and execute gcc test.c -o test && ./test and post the output.

[polygamma]

For further reference see e.g. https://www.gnu.org/software/libc/manual/html_node/Controlling-Buffering.html

The size should be at least 256, but it seems like it's not on your system.

[polygamma]

@hansheijmans - please install expac-git via the following PKGBUILD

# Contributor: Dave Reisner <d@falconindy.com>

pkgname=expac-git
pkgver=9
pkgrel=2
pkgdesc="pacman database extraction utility"
arch=('i686' 'x86_64')
url="http://github.com/falconindy/expac"
license=('MIT')
depends=('pacman')
makedepends=('git' 'perl')
conflicts=('expac')
provides=('expac')
source=('git://github.com/falconindy/expac.git'
        'https://pastebin.com/raw/mxExySAd')
md5sums=('SKIP'
         'SKIP')

prepare() {
    cd $srcdir

    patch expac/expac.c mxExySAd
}

pkgver() {
  cd expac

  git describe | sed 's/-/./g'
}

build() {
  cd expac

  make
}

package() {
  cd expac

  make PREFIX=/usr DESTDIR="$pkgdir" install
}

# vim: ft=sh syn=sh et

it installs the current expac-git version, but applies the following patch for debugging purposes:

From 2334e8fb9c3a4e6edfe21bd96df8cfa60994dcb3 Mon Sep 17 00:00:00 2001
From: Jonni Westphalen <jonny.westphalen@googlemail.com>
Date: Thu, 5 Jul 2018 12:14:14 +0200
Subject: [PATCH] expac debug

---
 expac.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/expac.c b/expac.c
index 3528e06..118a510 100644
--- a/expac.c
+++ b/expac.c
@@ -799,14 +799,19 @@ static int read_targets_from_file(FILE *in, alpm_list_t **targets)
 {
   char line[BUFSIZ];
   int i = 0, end = 0, targets_added = 0;
+  unsigned int global_counter = 0;
 
   while(!end) {
     line[i] = fgetc(in);
+    printf("char %u: %c\n", ++global_counter, line[i]);
 
-    if(line[i] == EOF)
+    if(line[i] == EOF) {
+      printf("EOF reached at global char %u\n", global_counter);
       end = 1;
+    }
 
     if(isspace(line[i]) || end) {
+      printf("char %c is end or space, replacing with nullterminator\n", line[i]);
       line[i] = '\0';
       /* avoid adding zero length arg, if multiple spaces separate args */
       if(i > 0) {
@@ -823,6 +828,8 @@ static int read_targets_from_file(FILE *in, alpm_list_t **targets)
         return -1;
       }
     }
+
+    printf("\n");
   }
 
   return targets_added;
-- 
2.18.0

after that, post the full output of the following command you already ran:
printf "%s\n" aurman aurman-git expac expac-git | expac -Q "%n %v" -

[polygamma]

Nevermind: I know what the problem is, char is unsigned on ARM, the return value of fgetc is going to be casted to something besides EOF all the time, because it is being saved in a char[], thus never as -1, thus line[i] == EOF is never true and thus the overflow. Going to prepare a proper patch and open a PR in the expac repo.

@polygamma You can try it by yourself under your x86_64 Arch Linux.

1. Become root user: sudo su
2. Install emulation software: qemu-user-static and binfmt-support-git from AUR
3. Download ArchLinux ARM (armv7) image: wget http://os.archlinuxarm.org/os/ArchLinuxARM-armv7-latest.tar.gz
4. Make empty disk image: dd if=/dev/zero of=diskimage bs=1M count=8092
5. Create EXT-4 filesystem on it: mkfs.ext4 -F diskimage
6. Make directory to mount: mkdir alarmv7
7. Mount disk image: mount diskimage alarmv7
8. Unpack Arch Linux ARM system files: bsdtar -xf ArchLinuxARM-armv7-latest.tar.gz -C alarmv7
9. Copy emulation module into it: cp /usr/bin/qemu-arm-static alarmv7/usr/bin
10. Chroot into system: chroot alarmv7
11. Check network: ping 8.8.8.8, it should work now
12. Remove symlink to systemd resolv.conf: rm /etc/resolv.conf
13. Setup nameserver: echo "nameserver 8.8.8.8" > /etc/resolv.conf
14. Check web: ping google.com
    Now you're in Arch LInux ARM with 8GB memory and network connection. Hope it will be useful.

[polygamma]

step 10 yields: chroot: failed to run command ‘/bin/bash’: Exec format error

[polygamma]

By following https://gist.github.com/mikkeloscar/a85b08881c437795c1b9 I was able to get it running, I have built expac-git including my fix found here: falconindy/expac@8d6429b and can confirm, that it indeed fixes the issue, see:

[root@jonny-arch-pc /]# printf "%s\n" aurman aurman-git expac expac-git | expac -Q "%n %v" -
expac-git 9.1.gd15538e-1

Going to open a PR in the expac repo.

[polygamma]

done, see: falconindy/expac#37