Re: [SYSFS] Kernel Null pointer dereference in sysfs_readdir()

[Steven Rostedt <rostedt@goodmis.org>]

On Wed, 2006-07-12 at 13:35 +0200, Duetsch, Thomas LDE1 wrote:
> Hi,
> 
> I'm currently working on a custom kernel based on Ingo's -rt patch
> (2.6.16-rt29).
> 
> While rebooting my machine, I came across a kernel null pointer
> dereference in this code segment in fs/sysfs/dir.c, function
> sysfs_readdir():
> 
> 		for (p=q->next; p!= &parent_sd->s_children; p=p->next) {
> 			struct sysfs_dirent *next;
> 			const char * name;
> 			int len;
> 
> 			next = list_entry(p, struct sysfs_dirent,
> 					   s_sibling);
> 			if (!next->s_element)
> 				continue;
> 
> 			name = sysfs_get_name(next);
> 			len = strlen(name);
> 			if (next->s_dentry)
> PROBLEM ->			ino = next->s_dentry->d_inode->i_ino;
> 			else
> 				ino = iunique(sysfs_sb, 2);
> 

Hi Thomas,

Do you have a backtrace to look at? It might be helpful to see what
functions brought us to this point. Also it might help to determine if
the problem is vanilla, -rt, or the custom kernel.

Thanks,

-- Steve