Re: [PATCH 07/33] libceph: safely decode max_osd value in osdmap_decode()

[Alex Elder <elder@ieee.org>]

On 03/27/2014 01:17 PM, Ilya Dryomov wrote:
> max_osd value is not covered by any ceph_decode_need().  Use a safe
> version of ceph_decode_* macro to decode it.

I know it's slightly more efficient, but I never liked those
ceph_decode_need() statements that added together a bunch
of things you're about to go decode...

Anyway, this is the right thing to do.

Looks good.

Reviewed-by: Alex Elder <elder@linaro.org>

> Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
> ---
>  net/ceph/osdmap.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c
> index 298d076eee89..ec06010657b3 100644
> --- a/net/ceph/osdmap.c
> +++ b/net/ceph/osdmap.c
> @@ -687,9 +687,10 @@ static int osdmap_set_max_osd(struct ceph_osdmap *map, int max)
>  static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map)
>  {
>  	u16 version;
> -	u32 len, max, i;
>  	u32 epoch = 0;
>  	void *start = *p;
> +	u32 max;
> +	u32 len, i;
>  	int err;
>  	struct ceph_pg_pool_info *pi;
>  
> @@ -736,7 +737,8 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map)
>  
>  	ceph_decode_32_safe(p, end, map->flags, e_inval);
>  
> -	max = ceph_decode_32(p);
> +	/* max_osd */
> +	ceph_decode_32_safe(p, end, max, e_inval);
>  
>  	/* (re)alloc osd arrays */
>  	err = osdmap_set_max_osd(map, max);
>