Re: [PATCH net] rxrpc: Work around usercopy check

2018-02-16 Thread David Miller
From: David Howells 
Date: Thu, 15 Feb 2018 22:59:00 +

> Due to a check recently added to copy_to_user(), it's now not permitted to
> copy from slab-held data to userspace unless the slab is whitelisted.  This
> affects rxrpc_recvmsg() when it attempts to place an RXRPC_USER_CALL_ID
> control message in the userspace control message buffer.  A warning is
> generated by usercopy_warn() because the source is the copy of the
> user_call_ID retained in the rxrpc_call struct.
> 
> Work around the issue by copying the user_call_ID to a variable on the
> stack and passing that to put_cmsg().
> 
> The warning generated looks like:
 ...
> Reported-by: Jonathan Billings 
> Signed-off-by: David Howells 
> Acked-by: Kees Cook 
> Tested-by: Jonathan Billings 

Applied, thanks David.


Re: [PATCH net] rxrpc: Work around usercopy check

2018-02-16 Thread David Miller
From: David Howells 
Date: Thu, 15 Feb 2018 22:59:00 +

> Due to a check recently added to copy_to_user(), it's now not permitted to
> copy from slab-held data to userspace unless the slab is whitelisted.  This
> affects rxrpc_recvmsg() when it attempts to place an RXRPC_USER_CALL_ID
> control message in the userspace control message buffer.  A warning is
> generated by usercopy_warn() because the source is the copy of the
> user_call_ID retained in the rxrpc_call struct.
> 
> Work around the issue by copying the user_call_ID to a variable on the
> stack and passing that to put_cmsg().
> 
> The warning generated looks like:
 ...
> Reported-by: Jonathan Billings 
> Signed-off-by: David Howells 
> Acked-by: Kees Cook 
> Tested-by: Jonathan Billings 

Applied, thanks David.