Re: Linux 2.4.33-rc1

[Willy Tarreau <w@1wt.eu>]

On Mon, Jun 19, 2006 at 06:53:31PM +1000, Grant Coady wrote:
> On Mon, 19 Jun 2006 10:06:51 +0200, Willy Tarreau <w@1wt.eu> wrote:
> 
> >Hi Grant,
> >
> >OK, it does *really* crash in vfs_unlink(), during the double_up on
> >dentry->inode-i_zombie (dentry->inode = NULL).
> >
> >I suggest the following fix, I hope that it is correct and is not subject
> >to any race condition :
> >
> >--- ./fs/namei.c.orig	2006-06-19 09:39:52.000000000 +0200
> >+++ ./fs/namei.c	2006-06-19 09:51:09.000000000 +0200
> >@@ -1478,12 +1478,14 @@
> > int vfs_unlink(struct inode *dir, struct dentry *dentry)
> > {
> > 	int error;
> >+	struct inode *inode;
> > 
> > 	error = may_delete(dir, dentry, 0);
> > 	if (error)
> > 		return error;
> > 
> >-	double_down(&dir->i_zombie, &dentry->d_inode->i_zombie);
> >+	inode = dentry->d_inode;
> >+	double_down(&dir->i_zombie, &inode->i_zombie);
> > 	error = -EPERM;
> > 	if (dir->i_op && dir->i_op->unlink) {
> > 		DQUOT_INIT(dir);
> >@@ -1495,7 +1497,7 @@
> > 			unlock_kernel();
> > 		}
> > 	}
> >-	double_up(&dir->i_zombie, &dentry->d_inode->i_zombie);
> >+	double_up(&dir->i_zombie, &inode->i_zombie);
> > 	if (!error) {
> > 		d_delete(dentry);
> > 		inode_dir_notify(dir, DN_DELETE);
> >
> >I think it will *not* oops anymore with this fix, but I'd like someone to
> >review it to ensure that it is valid.
> 
> Hi Willy,
> 
> Still corrupts a vim edit backup filename as previously reported, 
> instead of /etc/lilo.conf~ I get /etc/lilo.co~ :(

Ok, thanks. At least we're making progress.

Could you try on another file, with fewer chars after the dot ? I suspect
that one particular error is reported to vim and that it retries with a
shorter name, for instance to be compatible with 8.3. If this is the case,
the problem might be in vfs_link() (but I don't see why).

> Grant.

Cheers,
Willy

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