Re: Bug in /proc/lvm/global (garbage printed)

[Thorsten Kukuk]

On Sat, Nov 10, Andreas Dilger wrote:

> On Nov 10, 2001  12:06 +0100, Thorsten Kukuk wrote:
> > The problem is in the _proc_read_global function. This function does
> > not use the "page" parameter to return the data. Instead it allocates
> > it's own buffer and change to "start" parameter to point to it.
> > 
> > --- drivers/md/lvm-fs.c	2001/11/09 19:00:38	1.1
> > +++ drivers/md/lvm-fs.c	2001/11/09 20:50:16
> > @@ -482,11 +480,15 @@
> >  		buf = NULL;
> >  		return 0;
> >  	}
> > -	*start = &buf[pos];
> > -	if (sz - pos < count)
> > +	/* *start = &buf[pos]; */
> > +	if (sz - pos < count) {
> > +		memcpy (page, &buf[pos], sz - pos);
> >  		return sz - pos;
> > -	else
> > +        }
> > +	else {
> > +		memcpy (page, &buf[pos], count);
> >  		return count;
> > +	}
> >  
> >  #undef LVM_PROC_BUF
> >  }
> 
> What version of LVM do you have?  This code looks different than mine.
> The file lvm-fs.c does not exist in Linus kernels, only in patched kernels.

This is from LVM 1.0.1-rc4. But all previous versions have the same
problem, the function here is lvm_proc_get_global_info() in 
drivers/md/lvm.c. The fix is also the same.

  Thorsten

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Thorsten Kukuk       http://www.suse.de/~kukuk/        [e-mail]
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