RE: Patch "RDMA/cma: Consider scope_id while binding to ipv6 ll address" has been added to the 4.4-stable tree

[Parav Pandit <parav@xxxxxxxxxxxx>]

Hi Sasha,

> -----Original Message-----
> From: Sasha Levin <sashal@xxxxxxxxxx>
> Sent: Thursday, May 30, 2019 5:32 AM
> To: Parav Pandit <parav@xxxxxxxxxxxx>
> Cc: stable-commits@xxxxxxxxxxxxxxx
> Subject: Patch "RDMA/cma: Consider scope_id while binding to ipv6 ll address"
> has been added to the 4.4-stable tree
> 
> This is a note to let you know that I've just added the patch titled
> 
>     RDMA/cma: Consider scope_id while binding to ipv6 ll address
> 
> to the 4.4-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-
> queue.git;a=summary
> 
> The filename of the patch is:
>      rdma-cma-consider-scope_id-while-binding-to-ipv6-ll-.patch
> and it can be found in the queue-4.4 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree, please let
> <stable@xxxxxxxxxxxxxxx> know about it.
> 
This patch depends on another patch [1] in same series.

However, these two patches only make sense on the kernels which has commit [2].
Patch [2] is not available in 4.4, 4.9 and 4.14 kernels.

Therefore, patch in this email should not be applied to 4.4, 4.9 and 4.14 kernel trees.

[1] commit 823b23da71132b80d9f41ab667c68b112455f3b6 ("IB/core: Allow vlan link local address based RoCE GIDs")
[2] 1060f86534147c2830db4bbc9dd849d1892a611b ("IB/{core/cm}: Fix generating a return AH for RoCEE")



> 
> 
> commit 33963c60bb63145227c96a9593526841d7f74809
> Author: Parav Pandit <parav@xxxxxxxxxxxx>
> Date:   Wed Apr 10 11:23:04 2019 +0300
> 
>     RDMA/cma: Consider scope_id while binding to ipv6 ll address
> 
>     [ Upstream commit 5d7ed2f27bbd482fd29e6b2e204b1a1ee8a0b268 ]
> 
>     When two netdev have same link local addresses (such as vlan and non
>     vlan), two rdma cm listen id should be able to bind to following different
>     addresses.
> 
>     listener-1: addr=lla, scope_id=A, port=X
>     listener-2: addr=lla, scope_id=B, port=X
> 
>     However while comparing the addresses only addr and port are considered,
>     due to which 2nd listener fails to listen.
> 
>     In below example of two listeners, 2nd listener is failing with address in
>     use error.
> 
>     $ rping -sv -a fe80::268a:7ff:feb3:d113%ens2f1 -p 4545&
> 
>     $ rping -sv -a fe80::268a:7ff:feb3:d113%ens2f1.200 -p 4545
>     rdma_bind_addr: Address already in use
> 
>     To overcome this, consider the scope_ids as well which forms the accurate
>     IPv6 link local address.
> 
>     Signed-off-by: Parav Pandit <parav@xxxxxxxxxxxx>
>     Reviewed-by: Daniel Jurgens <danielj@xxxxxxxxxxxx>
>     Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
>     Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
>     Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> 
> diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
> index 1454290078def..76e7eca35a110 100644
> --- a/drivers/infiniband/core/cma.c
> +++ b/drivers/infiniband/core/cma.c
> @@ -902,18 +902,31 @@ static inline int cma_any_addr(struct sockaddr
> *addr)
>  	return cma_zero_addr(addr) || cma_loopback_addr(addr);  }
> 
> -static int cma_addr_cmp(struct sockaddr *src, struct sockaddr *dst)
> +static int cma_addr_cmp(const struct sockaddr *src, const struct
> +sockaddr *dst)
>  {
>  	if (src->sa_family != dst->sa_family)
>  		return -1;
> 
>  	switch (src->sa_family) {
>  	case AF_INET:
> -		return ((struct sockaddr_in *) src)->sin_addr.s_addr !=
> -		       ((struct sockaddr_in *) dst)->sin_addr.s_addr;
> -	case AF_INET6:
> -		return ipv6_addr_cmp(&((struct sockaddr_in6 *) src)-
> >sin6_addr,
> -				     &((struct sockaddr_in6 *) dst)->sin6_addr);
> +		return ((struct sockaddr_in *)src)->sin_addr.s_addr !=
> +		       ((struct sockaddr_in *)dst)->sin_addr.s_addr;
> +	case AF_INET6: {
> +		struct sockaddr_in6 *src_addr6 = (struct sockaddr_in6 *)src;
> +		struct sockaddr_in6 *dst_addr6 = (struct sockaddr_in6 *)dst;
> +		bool link_local;
> +
> +		if (ipv6_addr_cmp(&src_addr6->sin6_addr,
> +					  &dst_addr6->sin6_addr))
> +			return 1;
> +		link_local = ipv6_addr_type(&dst_addr6->sin6_addr) &
> +			     IPV6_ADDR_LINKLOCAL;
> +		/* Link local must match their scope_ids */
> +		return link_local ? (src_addr6->sin6_scope_id !=
> +				     dst_addr6->sin6_scope_id) :
> +				    0;
> +	}
> +
>  	default:
>  		return ib_addr_cmp(&((struct sockaddr_ib *) src)->sib_addr,
>  				   &((struct sockaddr_ib *) dst)->sib_addr);