[Cluster-devel] [GFS2 PATCH] GFS2: Fix infinite loop in rbm_find

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Now in the -nmw git tree. Thanks,

Steve.

On Wed, 2012-09-12 at 09:40 -0400, Bob Peterson wrote:
> Hi,
> 
> This patch fixes an infinite loop in gfs2_rbm_find that was introduced
> by the previous patch. The problem occurred when the length was less
> than 3 but the rbm block was byte-aligned, causing it to improperly
> return a extent length of zero, which caused it to spin.
> 
> Regards,
> 
> Bob Peterson
> Red Hat File Systems
> 
> Signed-off-by: Bob Peterson <rpeterso@redhat.com> 
> ---
>  fs/gfs2/rgrp.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
> index b933cdc..3cc402c 100644
> --- a/fs/gfs2/rgrp.c
> +++ b/fs/gfs2/rgrp.c
> @@ -329,6 +329,7 @@ static u32 gfs2_free_extlen(const struct gfs2_rbm *rrbm, u32 len)
>  	    gfs2_unaligned_extlen(&rbm, 4 - n_unaligned, &len))
>  		goto out;
>  
> +	n_unaligned = len & 3;
>  	/* Start is now byte aligned */
>  	while (len > 3) {
>  		start = rbm.bi->bi_bh->b_data;
>