Re: [PATCH v1 01/16] nfsd: fix IPv6 address handling in the DRC

["J. Bruce Fields" <bfields@fieldses.org>]

On Mon, Jan 28, 2013 at 02:41:07PM -0500, Jeff Layton wrote:
> Currently, it only stores the first 16 bytes of any address. struct
> sockaddr_in6 is 28 bytes however, so we're currently ignoring the last
> 12 bytes of the address.
> 
> Expand the c_addr field to a sockaddr_in6, and cast it to a sockaddr_in
> as necessary. Also fix the comparitor to use the existing RPC
> helpers for this.

Applying.  (Assuming the fix for link-local case will be separate.)

--b.

> 
> Signed-off-by: Jeff Layton <jlayton@redhat.com>
> ---
>  fs/nfsd/cache.h             | 6 +++++-
>  fs/nfsd/nfscache.c          | 7 +++++--
>  include/linux/sunrpc/clnt.h | 4 +++-
>  3 files changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/nfsd/cache.h b/fs/nfsd/cache.h
> index 93cc9d3..2cac76c 100644
> --- a/fs/nfsd/cache.h
> +++ b/fs/nfsd/cache.h
> @@ -12,6 +12,10 @@
>  
>  /*
>   * Representation of a reply cache entry.
> + *
> + * Note that we use a sockaddr_in6 to hold the address instead of the more
> + * typical sockaddr_storage. This is for space reasons, since sockaddr_storage
> + * is much larger than a sockaddr_in6.
>   */
>  struct svc_cacherep {
>  	struct hlist_node	c_hash;
> @@ -20,7 +24,7 @@ struct svc_cacherep {
>  	unsigned char		c_state,	/* unused, inprog, done */
>  				c_type,		/* status, buffer */
>  				c_secure : 1;	/* req came from port < 1024 */
> -	struct sockaddr_in	c_addr;
> +	struct sockaddr_in6	c_addr;
>  	__be32			c_xid;
>  	u32			c_prot;
>  	u32			c_proc;
> diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
> index 2cbac34..5dd9ec2 100644
> --- a/fs/nfsd/nfscache.c
> +++ b/fs/nfsd/nfscache.c
> @@ -9,6 +9,7 @@
>   */
>  
>  #include <linux/slab.h>
> +#include <linux/sunrpc/clnt.h>
>  
>  #include "nfsd.h"
>  #include "cache.h"
> @@ -146,7 +147,8 @@ nfsd_cache_lookup(struct svc_rqst *rqstp)
>  		    xid == rp->c_xid && proc == rp->c_proc &&
>  		    proto == rp->c_prot && vers == rp->c_vers &&
>  		    time_before(jiffies, rp->c_timestamp + 120*HZ) &&
> -		    memcmp((char*)&rqstp->rq_addr, (char*)&rp->c_addr, sizeof(rp->c_addr))==0) {
> +		    rpc_cmp_addr(svc_addr(rqstp), (struct sockaddr *)&rp->c_addr) &&
> +		    rpc_get_port(svc_addr(rqstp)) == rpc_get_port((struct sockaddr *)&rp->c_addr)) {
>  			nfsdstats.rchits++;
>  			goto found_entry;
>  		}
> @@ -183,7 +185,8 @@ nfsd_cache_lookup(struct svc_rqst *rqstp)
>  	rp->c_state = RC_INPROG;
>  	rp->c_xid = xid;
>  	rp->c_proc = proc;
> -	memcpy(&rp->c_addr, svc_addr_in(rqstp), sizeof(rp->c_addr));
> +	rpc_copy_addr((struct sockaddr *)&rp->c_addr, svc_addr(rqstp));
> +	rpc_set_port((struct sockaddr *)&rp->c_addr, rpc_get_port(svc_addr(rqstp)));
>  	rp->c_prot = proto;
>  	rp->c_vers = vers;
>  	rp->c_timestamp = jiffies;
> diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
> index 34206b8..47354a2 100644
> --- a/include/linux/sunrpc/clnt.h
> +++ b/include/linux/sunrpc/clnt.h
> @@ -263,7 +263,9 @@ static inline bool __rpc_copy_addr6(struct sockaddr *dst,
>   * @sap1: first sockaddr
>   * @sap2: second sockaddr
>   *
> - * Just compares the family and address portion. Ignores port, scope, etc.
> + * Just compares the family and address portion. Ignores port, but
> + * compares the scope if it's a link-local address.
> + *
>   * Returns true if the addrs are equal, false if they aren't.
>   */
>  static inline bool rpc_cmp_addr(const struct sockaddr *sap1,
> -- 
> 1.7.11.7
>