linux-kernel - [PATCH V2 3/3] cifs: Add CONFIG_CIFS_DEBUG and rename use of CIFS

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 30 Nov 2012 07:31:56 -0800
From:	Joe Perches <joe@...ches.com>
To:	Jeff Layton <jlayton@...hat.com>
Cc:	Steve French <sfrench@...ba.org>, linux-cifs@...r.kernel.org,
	samba-technical@...ts.samba.org, linux-kernel@...r.kernel.org
Subject: [PATCH V2 3/3] cifs: Add CONFIG_CIFS_DEBUG and rename use of
 CIFS_DEBUG

On Fri, 2012-11-30 at 10:07 -0500, Jeff Layton wrote:
> On Fri, 30 Nov 2012 06:57:40 -0800
> Joe Perches <joe@...ches.com> wrote:
> > On Fri, 2012-11-30 at 06:56 -0500, Jeff Layton wrote:
> > > On Thu, 29 Nov 2012 11:37:20 -0800
> > > Joe Perches <joe@...ches.com> wrote:
> > > > Rather than havign a permanently enabled #define, allow
> > > > control over it.
> > > > 
> > > > This can reduce the size of the module by ~100KB which
> > > > could be useful for embedded systems.
> > []
> > > > diff --git a/fs/cifs/cifs_debug.h b/fs/cifs/cifs_debug.h
> > > > index 4d12fe4..6867a7f 100644
> > > > --- a/fs/cifs/cifs_debug.h
> > > > +++ b/fs/cifs/cifs_debug.h
> > > > @@ -18,7 +18,10 @@
> > > >   *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> > > >   *
> > > >  */
> > > > -#define CIFS_DEBUG		/* BB temporary */
> > > > +
> > > > +#ifdef CONFIG_CIFS_DEBUG
> > > > +#define CIFS_DEBUG
> > > > +#endif
> > > >  
> > > >  #ifndef _H_CIFS_DEBUG
> > > >  #define _H_CIFS_DEBUG
> > > 
> > > Looks fine, but I'd probably prefer to just get rid of CIFS_DEBUG
> > > altogether here and replace it with CONFIG_CIFS_DEBUG.
> > 
> > I wasn't sure if there was other code anywhere else that depends
> > on CIFS_DEBUG.  There isn't any in the kernel source tree.  If not,
> > then you are right, it should be just CONFIG_CIFS_DEBUG.
> There shouldn't be. None of this stuff is exposed to userspace, AFAIK.
> I think it's ok to just make that CONFIG_CIFS_DEBUG.
> 
> > > While you're at it, /proc/fs/cifs/cifsFYI should probably not be
> > > present when CONFIG_CIFS_DEBUG isn't set. Perhaps we should also
> > > disable traceSMB and its related functions too in that case?
> > 
> > That could be considered a kernel api change.
> > If people agree to delete it, I'd be OK with it.
> > 
> 
> If you compile with CONFIG_CIFS_DEBUG turned off, then the cifsFYI file
> will be a knob that's not hooked up to anything. I think it's best not
> to present it at all in that case.

If there's a userspace script that does
echo 1 > /proc/fs/cifs/cifsFYI
it'd now get a file not found error.

> traceSMB is a little harder to make the case for. Theoretically, it'll
> still work after your changes, but I'm not sure it makes sense to leave
> that knob around since it's technically a flag for debugging. You're
> probably fine not to worry about that one. I'll look at that at some
> point in the future.

This could be changed in a separate patch if appropriate.
Here's the modified patch.

From: Joe Perches <joe@...ches.com>

This can reduce the size of the module by ~120KB which
could be useful for embedded systems.

$ size fs/cifs/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 388567	  34459	 100440	 523466	  7fcca	fs/cifs/built-in.o.new
 495970	  34599	 117904	 648473	  9e519	fs/cifs/built-in.o.old

Signed-off-by: Joe Perches <joe@...ches.com>
---
 fs/cifs/Kconfig      |   10 +++++++++-
 fs/cifs/cifs_debug.h |    3 +--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index 2075ddf..21ff76c 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -122,9 +122,17 @@ config CIFS_ACL
 	    Allows fetching CIFS/NTFS ACL from the server.  The DACL blob
 	    is handed over to the application/caller.
 
+config CIFS_DEBUG
+	bool "Enable CIFS debugging routines"
+	default y
+	depends on CIFS
+	help
+	   Enabling this option adds helpful debugging messages to
+	   the cifs code which increases the size of the cifs module.
+	   If unsure, say Y.
 config CIFS_DEBUG2
 	bool "Enable additional CIFS debugging routines"
-	depends on CIFS
+	depends on CIFS_DEBUG
 	help
 	   Enabling this option adds a few more debugging routines
 	   to the cifs code which slightly increases the size of
diff --git a/fs/cifs/cifs_debug.h b/fs/cifs/cifs_debug.h
index 4d12fe4..86e92ef 100644
--- a/fs/cifs/cifs_debug.h
+++ b/fs/cifs/cifs_debug.h
@@ -18,7 +18,6 @@
  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  *
 */
-#define CIFS_DEBUG		/* BB temporary */
 
 #ifndef _H_CIFS_DEBUG
 #define _H_CIFS_DEBUG
@@ -44,7 +43,7 @@ extern int cifsERROR;
  *	debug ON
  *	--------
  */
-#ifdef CIFS_DEBUG
+#ifdef CONFIG_CIFS_DEBUG
 
 /* information message: e.g., configuration, major event */
 #define cifsfyi(fmt, ...)						\
-- 
1.7.8.112.g3fd21


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/