From: Kyle Moffett <mrmacman_g4@mac.com>
To: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>,
akpm@osdl.org, torvalds@osdl.org,
linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Smackv10: Smack rules grammar + their stateful parser
Date: Sat, 3 Nov 2007 14:30:30 -0400 [thread overview]
Message-ID: <45A82524-172E-4F18-B660-981D5A1A6D75@mac.com> (raw)
In-Reply-To: <20071103164303.GA26707@ubuntu>
On Nov 03, 2007, at 12:43:06, Ahmed S. Darwish wrote:
> Bashv3 builtin "echo" behaves very strangely to -EINVAL. It sends
> all the buffers that causes -EINVAL again in subsequent echo
> invocations.
>
> i.e.
> echo "Invalid Rule" > /smack/load # -EINVAL returned
> echo "Valid Rule" > /smack/load
>
> In seconod iteration, echo sends the first invalid buffer again
> then sends the new one. This causes a "Invalid Rule\nValid Rule"
> buffer sent to write().
>
> IMHO, this is a bug in builtin echo. The external /bin/echo doesn't
> cause such strange behaviour.
Actually, what causes problems here is something between a bug and a
feature in libc's buffering. Basically the -EINVAL error causes libc
to leave its data in the file-output buffer despite the file being
closed and reopened. Since a standalone echo just exits that buffer
is discarded, but for the bash builtin it hangs around in the buffer
for a while and ends up getting prepended to the following echo
statement. There's actually multiple ways to make this fail; this is
just the simplest.
Cheers,
Kyle Moffett
next prev parent reply other threads:[~2007-11-03 18:30 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-02 20:50 [PATCH] Version 10 (2.6.24-rc1) Smack: Simplified Mandatory Access Control Kernel Casey Schaufler
2007-11-03 16:43 ` [PATCH] Smackv10: Smack rules grammar + their stateful parser Ahmed S. Darwish
2007-11-03 18:30 ` Kyle Moffett [this message]
2007-11-03 22:12 ` Ahmed S. Darwish
2007-11-04 12:28 ` Pavel Machek
2007-11-04 13:23 ` Ahmed S. Darwish
2007-11-04 16:37 ` Casey Schaufler
2007-11-05 9:41 ` Ahmed S. Darwish
2007-11-05 16:21 ` Linus Torvalds
2007-11-05 21:56 ` Tetsuo Handa
2007-11-06 10:00 ` Adrian Bunk
2007-11-06 12:27 ` Tetsuo Handa
2007-11-06 13:58 ` Adrian Bunk
2007-11-06 14:32 ` Tetsuo Handa
2007-11-06 14:59 ` Adrian Bunk
2007-11-06 15:27 ` Tetsuo Handa
2007-11-06 22:42 ` Adrian Bunk
2007-11-05 23:38 ` Ahmed S. Darwish
2007-11-06 8:06 ` Adrian Bunk
2007-11-06 15:39 ` Linus Torvalds
2007-11-06 23:00 ` Adrian Bunk
2007-11-06 23:08 ` Linus Torvalds
2007-11-07 0:07 ` Adrian Bunk
2007-11-07 0:27 ` Linus Torvalds
2007-11-07 0:43 ` Adrian Bunk
2007-11-07 1:03 ` Tetsuo Handa
2007-11-07 1:06 ` Linus Torvalds
2007-11-07 1:59 ` Adrian Bunk
2007-11-07 4:09 ` Linus Torvalds
2007-11-07 15:08 ` Alan Cox
2007-11-04 20:06 ` Ahmed S. Darwish
2007-11-05 0:56 ` [PATCH] Smackv10: Smack rules grammar + their stateful parser(2) Ahmed S. Darwish
2007-11-10 17:05 ` Jakob Oestergaard
2007-11-10 19:45 ` Ahmed S. Darwish
2007-11-11 12:44 ` Pavel Machek
2007-11-11 18:37 ` Ahmed S. Darwish
2007-11-06 6:33 ` [PATCH] Smackv10: Smack rules grammar + their stateful parser Adrian Bunk
2007-11-06 8:26 ` Kyle Moffett
2007-11-06 8:56 ` Adrian Bunk
2007-11-06 11:02 ` Alan Cox
2007-11-06 11:34 ` Ahmed S. Darwish
2007-11-06 11:47 ` Adrian Bunk
2007-11-06 12:23 ` Ahmed S. Darwish
2007-11-06 12:49 ` Kyle Moffett
2007-11-06 13:34 ` Adrian Bunk
2007-11-06 14:05 ` Ahmed S. Darwish
2007-11-06 14:10 ` Adrian Bunk
2007-11-06 14:30 ` Ahmed S. Darwish
2007-11-06 15:53 ` Linus Torvalds
2007-11-07 10:56 ` [PATCH] Fix isspace() and other ctype.h functions to ignore chars 128-255 Kyle Moffett
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=45A82524-172E-4F18-B660-981D5A1A6D75@mac.com \
--to=mrmacman_g4@mac.com \
--cc=akpm@osdl.org \
--cc=casey@schaufler-ca.com \
--cc=darwish.07@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=torvalds@osdl.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).