From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o19KLhGW247951 for ; Tue, 9 Feb 2010 14:21:43 -0600 Subject: Re: [PATCH] xfs: only clear the suid bit once in xfs_write From: Alex Elder In-Reply-To: <20100203194331.GA20199@infradead.org> References: <20100203194331.GA20199@infradead.org> Date: Tue, 09 Feb 2010 14:22:53 -0600 Message-ID: <1265746973.26394.9.camel@doink1> Mime-Version: 1.0 Reply-To: aelder@sgi.com List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Christoph Hellwig Cc: xfs@oss.sgi.com On Wed, 2010-02-03 at 14:43 -0500, Christoph Hellwig wrote: > file_remove_suid already calls into ->setattr to clear the suid and sgid > bits if needed, no need to start a second transaction to do it ourselves. > > Note that xfs_write_clear_setuid issues a sync transaction while the > path through ->setattr doesn't, but that is consistant with the other > filesystems. > > Signed-off-by: Christoph Hellwig Looks good. Those S*ID bits sure get checked and cleared in a lot of places... Reviewed-by: Alex Elder > Index: xfs/fs/xfs/linux-2.6/xfs_lrw.c > =================================================================== > --- xfs.orig/fs/xfs/linux-2.6/xfs_lrw.c 2010-02-03 20:37:45.956003749 +0100 > +++ xfs/fs/xfs/linux-2.6/xfs_lrw.c 2010-02-03 20:37:49.348003520 +0100 > @@ -630,18 +630,9 @@ start: > * by root. This keeps people from modifying setuid and > * setgid binaries. > */ > - > - if (((xip->i_d.di_mode & S_ISUID) || > - ((xip->i_d.di_mode & (S_ISGID | S_IXGRP)) == > - (S_ISGID | S_IXGRP))) && > - !capable(CAP_FSETID)) { > - error = xfs_write_clear_setuid(xip); > - if (likely(!error)) > - error = -file_remove_suid(file); > - if (unlikely(error)) { > - goto out_unlock_internal; > - } > - } > + error = -file_remove_suid(file); > + if (unlikely(error)) > + goto out_unlock_internal; > > /* We can write back this queue in page reclaim */ > current->backing_dev_info = mapping->backing_dev_info; > Index: xfs/fs/xfs/xfs_rw.c > =================================================================== > --- xfs.orig/fs/xfs/xfs_rw.c 2010-02-03 20:37:45.965004126 +0100 > +++ xfs/fs/xfs/xfs_rw.c 2010-02-03 20:37:49.349010212 +0100 > @@ -47,48 +47,6 @@ > #include "xfs_trace.h" > > /* > - * This is a subroutine for xfs_write() and other writers (xfs_ioctl) > - * which clears the setuid and setgid bits when a file is written. > - */ > -int > -xfs_write_clear_setuid( > - xfs_inode_t *ip) > -{ > - xfs_mount_t *mp; > - xfs_trans_t *tp; > - int error; > - > - mp = ip->i_mount; > - tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID); > - if ((error = xfs_trans_reserve(tp, 0, > - XFS_WRITEID_LOG_RES(mp), > - 0, 0, 0))) { > - xfs_trans_cancel(tp, 0); > - return error; > - } > - xfs_ilock(ip, XFS_ILOCK_EXCL); > - xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); > - xfs_trans_ihold(tp, ip); > - ip->i_d.di_mode &= ~S_ISUID; > - > - /* > - * Note that we don't have to worry about mandatory > - * file locking being disabled here because we only > - * clear the S_ISGID bit if the Group execute bit is > - * on, but if it was on then mandatory locking wouldn't > - * have been enabled. > - */ > - if (ip->i_d.di_mode & S_IXGRP) { > - ip->i_d.di_mode &= ~S_ISGID; > - } > - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); > - xfs_trans_set_sync(tp); > - error = xfs_trans_commit(tp, 0); > - xfs_iunlock(ip, XFS_ILOCK_EXCL); > - return 0; > -} > - > -/* > * Force a shutdown of the filesystem instantly while keeping > * the filesystem consistent. We don't do an unmount here; just shutdown > * the shop, make sure that absolutely nothing persistent happens to > Index: xfs/fs/xfs/xfs_rw.h > =================================================================== > --- xfs.orig/fs/xfs/xfs_rw.h 2010-02-03 20:37:53.085003394 +0100 > +++ xfs/fs/xfs/xfs_rw.h 2010-02-03 20:37:57.946033654 +0100 > @@ -39,7 +39,6 @@ xfs_fsb_to_db(struct xfs_inode *ip, xfs_ > /* > * Prototypes for functions in xfs_rw.c. > */ > -extern int xfs_write_clear_setuid(struct xfs_inode *ip); > extern int xfs_read_buf(struct xfs_mount *mp, xfs_buftarg_t *btp, > xfs_daddr_t blkno, int len, uint flags, > struct xfs_buf **bpp); > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs