Bug 3679

Summary:	uClibc with crosstool-ng builds buggy busybox (argument / parameter problem)
Product:	uClibc	Reporter:	John <smeeze>
Component:	Other	Assignee:	unassigned
Status:	RESOLVED WORKSFORME
Severity:	major	CC:	uclibc-cvs
Priority:	P4
Version:	0.9.30.2
Target Milestone:	---
Hardware:	PC
OS:	Linux
Host:	i486-linux	Target:	i486-linux
Build:	i486-linux

Description John 2011-05-01 01:11:29 UTC

When building busybox 1.18.4 with crosstool-ng 1.10.1 and uClibc 0.9.30.2 building GCC 4.2.4, busybox compiled to use hush improperly passes parameters to applets.
Example:
if you type 'busybox ls', it passes 'ls' as a argument to the applet 'ls' effectivly making it 'busybox ls ls'. Similarly 'busybox mount' passes 'mount' to mount. Linking busybox to 'ls' and calling 'ls' still exhibits the problem. This problem makes many applets malfunction. It is probably putting what should be in argv[0] into argv[1].

Comment 1 Bernhard Reutner-Fischer 2011-05-01 12:36:57 UTC

4.2.x is too buggy. Also, please use the current stable release (with 4.5.x)

Comment 2 John 2011-05-03 22:55:25 UTC

Waiting for rebuild (again)
It built a broken 4.5 compiler so I am trying 4.4

Comment 3 John 2011-05-06 18:49:50 UTC

Couldn't build a 4.5.x compiler but I built a 4.4.x compiler and the bug still exists.
"/busybox ls" == "/busybox ls ls"

Comment 4 Bernhard Reutner-Fischer 2011-05-06 20:14:09 UTC

So what do you see for:
cd /tmp
rm -f ls
ln -s /busybox ls
./ls -l

Comment 5 John 2011-05-06 21:10:47 UTC

(In reply to comment #4)
> So what do you see for:
> cd /tmp
> rm -f ls
> ln -s /busybox ls
> ./ls -l
/ # cd /tmp
/ # rm -f ls
Cannot remove ls: No such file or directory
/ # ln -s /busybox ls
/ # ./ls -l
ls: -l: No such file or directory
/bin/ls
/ #

Comment 6 John 2011-05-06 21:15:20 UTC

(In reply to comment #4)
> So what do you see for:
> cd /tmp
> rm -f ls
> ln -s /busybox ls
> ./ls -l
/ # cd /tmp
/ # rm -f ls
Cannot remove ls: No such file or directory
/ # ln -s /busybox ls
/ # ./ls -l
ls: -l: No such file or directory
./ls
/ # 

^^ Updated - I made a mistake copying from qemu

Comment 7 John 2011-05-07 19:05:37 UTC

Would a video of the offending bug help?

Comment 8 Bernhard Reutner-Fischer 2011-05-07 22:47:56 UTC

No, but ldd and strace output (assuming you do them with 0.9.31 or master).

Comment 9 John 2011-05-08 23:42:21 UTC

(In reply to comment #8)
> No, but ldd and strace output (assuming you do them with 0.9.31 or master).

Sorry, do not know how to use strace
$ ldd busybox
Checking sub-depends for '/usr/lib/libcrypt.so.0'
Checking sub-depends for '/usr/lib/uClibc.so.0'
        libcrypt.so.0 => /usr/lib/libcrypt.so.0 (0x00000000)
        uClibc.so.0 => /usr/lib/uClibc.so.0 (0x00000000)
        /lib/ld-uClibc.so.0 => /lib/ld-uClibc.so.0 (0x00000000)
$
^^ Isn't all zeros for the address alittle odd?

Comment 10 John 2011-05-13 01:25:22 UTC

Any suggestions?

Comment 11 John 2011-05-14 04:50:36 UTC

Here is a workaround patch
Apply to ./libbb/appletlib.c:
*** appletlib.c      2011-05-13 21:40:36.000000000 -0700
--- appletlib/c 2011-05-13 21:35:03.000000000 -0700
*************** void FAST_FUNC run_applet_no_and_exit(in
*** 763,769 ****
        }
        if (ENABLE_FEATURE_SUID) 
                check_suid(applet_no);
!       exit(applet_main[applet_no](argc, argv));
  }

  void FAST_FUNC run_applet_and_exit(const char *name, char **argv)
--- 763,769 ----
        }
        if (ENABLE_FEATURE_SUID)
                check_suid(applet_no);
!       exit(applet_main[applet_no](argc, argv+1));
  }

  void FAST_FUNC run_applet_and_exit(const char *name, char **argv)

Comment 12 John 2011-05-14 05:42:12 UTC

Issue though.
It causes it to Segmentation fault even more. (Randomly...Was doing it before, just not as much)

Comment 13 John 2012-08-25 02:49:10 UTC

I managed to find the core of the problem.
uClibc poses itself as glibc and defines __GLIBC__.
This causes the #ifdef __GLIBC__ to evaluate to true and resets optind to zero instead of one.
Unfortunately the uClibc getopt() is BSD style and pukes and keeps optind at zero.
Putting an exception for uClibc in 
libbb/getopt32.c
libbb/vfork_daemon_rexec.c
shell/shell_common.c
util-linux/getopt.c

fixed the problem.