linux-kernel - Re: [PATCH] btrfs: bugfix: handle FS_IOC32_{GETFLAGS,SETFLAGS,GETVERSION} in btrfs

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]

Message-Id: <201505141627.56205.luke@dashjr.org>
Date:	Thu, 14 May 2015 16:27:54 +0000
From:	Luke Dashjr <luke@...hjr.org>
To:	dsterba@...e.cz
Cc:	Chris Mason <clm@...com>, Josef Bacik <jbacik@...com>,
	linux-btrfs@...r.kernel.org, linux-kernel@...r.kernel.org,
	stable@...r.kernel.org, trivial@...nel.org
Subject: Re: [PATCH] btrfs: bugfix: handle FS_IOC32_{GETFLAGS,SETFLAGS,GETVERSION} in btrfs_ioctl

On Thursday, May 14, 2015 2:06:17 PM David Sterba wrote:
> On Wed, May 13, 2015 at 05:15:26PM +0000, Luke Dashjr wrote:
> > 32-bit ioctl uses these rather than the regular FS_IOC_* versions. They
> > can be handled in btrfs using the same code. Without this, 32-bit
> > {ch,ls}attr fail.
> 
> Yes, but this has to be implemented in another way. See eg.
> https://git.kernel.org/linus/e9750824114ff

I don't see what is different with that implementation. All f2fs_compat_ioctl 
does is change cmd to the plain-IOC equivalent and call f2fs_ioctl with the 
same arg (compat_ptr merely causes a cast to void* and back, which AFAIK is a 
noop on 64-bit?). Am I missing something? I could try to just imitate it, but 
I'd rather know what is significant/going on to ensure I don't waste your time 
with code I don't even properly understand myself.

Perhaps by coincidence, the patch does at least in practice work (although at 
least `btrfs send` appears to be broken still, and I'm at a loss for how to 
approach fixing that).

Luke
--
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/