From: Wolfgang Denk <wd@denx.de>
Date: Fri, 30 Sep 2005 16:03:53 GMT
Subject: Destructive side-effect of "cg-status"
Message-ID: <20050930160353.F025C352B7B@atlas.denx.de>

So far I  thought  "cg-status"  is  a  harmless  command  which  just
displays  some  status information. It ain't so. One of our engineers
reported a  corrupted  repository  after  I  ran  "cg-status"  in  his
directory:

$ cg-status
Heads:
   >master      805f93e4ca96d0c0cb2d2f9532d9666b22961e88
  R origin      805f93e4ca96d0c0cb2d2f9532d9666b22961e88

error: open failed
fatal: cache corrupted
error: open failed
? COPYING
? CREDITS
? Documentation/00-INDEX
? Documentation/BUG-HUNTING
...
error: open failed
read_cache: Permission denied
...
error: open failed
read_cache: Permission denied
...


As mentioned before,  all  I  did  was  running  "cg-status"  in  his
directory. Here is what happens:

Before:

	-> rpm -q cogito
	cogito-0.15.1-1
	-> id
	uid=500(wd) gid=500(wd) groups=200(gitmaster),400(denx),500(wd)
	-> umask
	0002
	-> ls -ld .git
	drwxrwxrwx  6 sr sr 80 Sep 30 17:49 .git
	-> ls -l .git/index
	-rw-r--r--  1 sr sr 1728032 Sep 30 17:17 .git/index

Then:

	-> cg-status
	Heads:
	   >master      805f93e4ca96d0c0cb2d2f9532d9666b22961e88
	  R origin      805f93e4ca96d0c0cb2d2f9532d9666b22961e88

	M arch/ppc/configs/bubinga_defconfig
	M arch/ppc/configs/walnut_defconfig
	-> ls -l .git/index
	-rw-------  1 wd wd 1728032 Sep 30 17:49 .git/index
	^^^^^^^^^^    ^^^^^

That means, that "cg-status" actually *rewrote* .git/index,  with  me
(wd)  as  new  owner, and - ignoring my umask - with permissions that
prevent the original owner (sr) to access the file!

Arghhhh!!!

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
Generally speaking, there are other ways to accomplish whatever it is
that you think you need ...                               - Doug Gwyn