linux-kernel - RE: NFS open/setuid/ftruncate problem

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:	Tue, 10 Jun 2008 22:24:49 -0700
From:	Luoqi Chen <Luoqi.Chen@...on.com>
To:	Trond Myklebust <trond.myklebust@....uio.no>
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-nfs@...r.kernel.org" <linux-nfs@...r.kernel.org>
Subject: RE: NFS open/setuid/ftruncate problem

> From: Trond Myklebust <Trond.Myklebust@...app.com>
> Date: Tue, 10 Jun 2008 19:39:41 -0400
> NFS: Fix the ftruncate() credential problem
>
> ftruncate() access checking is supposed to be performed at
> open() time,
> just like reads and writes.
>
Thanks, Trond. Is there any chance this patch could be
included in the linux kernel in the near future? For now,
I guess I'll workaround this problem by moving the ftruncate()
to before setuid().

-luoqi

PS: I haven't tried the patch, just browsing through, and I noticed
a typo, pointing out here to save some trouble for anyone who
wants to give it a try (I guess gcc would issue a warning too),

        /* Search for an existing open(O_WRITE) file */
-       ctx = nfs_find_open_context(inode, cred, FMODE_WRITE);
-       if (ctx != NULL)
-               state = ctx->state;
+       if (sattr->ia_valid && ATTR_FILE) {  <=== && should be &
+               ctx = nfs_file_open_context(sattr->ia_file);
+               if (ctx != NULL)
+                       state = ctx->state;
+       }
--
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/