Re: isofs oops - d_splice_alias+0x1f (2.6.24-rc5-mm1)

[Jiri Slaby <jirislaby@gmail.com>]

On 01/03/2008 02:51 PM, Pekka J Enberg wrote:
> Hi Jiri,
> 
> On Thu, 3 Jan 2008, Jiri Slaby wrote:
>> this happened, while playing with broken dvd.
> 
> [snip]
> 
>> Buffer I/O error on device sr0, logical block 5441
>> end_request: I/O error, dev sr0, sector 136
>> ISOFS: unable to read i-node block
>> Unable to handle kernel NULL pointer dereference at 00000000000000ad RIP:
>>  [<ffffffff802a679f>] d_splice_alias+0x1f/0x100
> 
> [snip]
> 
>> Call Trace:
>>  [<ffffffff880d2395>] :isofs:isofs_lookup+0x395/0x4a0
>>  [<ffffffff802a565b>] d_alloc+0x2b/0x1d0
>>  [<ffffffff8029a97c>] do_lookup+0x1ac/0x200
> 
> Does the following patch fix it?
> 
> 			Pekka
> 
> [PATCH] isofs: check for bad inode in isofs_lookup
> From: Pekka Enberg <penberg@cs.helsinki.fi>
> 
> If isofs_read_inode() fails to read one of the inode blocks from disk, it
> returns a bad inode.
> 
> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
> ---
>  fs/isofs/namei.c |    5 +++++
>  1 file changed, 5 insertions(+)
> 
> Index: linux-2.6/fs/isofs/namei.c
> ===================================================================
> --- linux-2.6.orig/fs/isofs/namei.c
> +++ linux-2.6/fs/isofs/namei.c
> @@ -183,6 +183,11 @@ struct dentry *isofs_lookup(struct inode
>  			unlock_kernel();
>  			return ERR_PTR(-EACCES);
>  		}
> +		if (is_bad_inode(inode)) {
> +			unlock_kernel();
> +			iput(inode);
> +			return ERR_PTR(-ENOENT);
> +		}
>  	}
>  	unlock_kernel();
>  	return d_splice_alias(inode, dentry);

Can't say, the DVD seems to be OK, I don't know what was wrong (as I can say,
this happened several times in the past yet and after reboot everything OK; I
suspect gnome auto mounter -- multiple machines, several DVD ROMs, same disk
with OS, similar errors, but that's too few to report).