Re: [PATCH 1/1] dccp: allow probing of CCID-array length

From: Gerrit Renker <redacted>
Date: Mon, 8 Feb 2010 07:20:28 +0100

This fixes a problem in the DCCP getsockopt() API: currently there is no way
for a user to a priori know the number of built-in CCIDs, other than trying
DCCP_SOCKOPT_AVAILABLE_CCIDS in a loop, incrementing the option length until
EINVAL is no longer returned.

This patch truncates the array to the user-provided length. No copy is made
when the length is <= 0.

Due to the length restriction in do_dccp_getsockopt() to sizeof(int), the
minimum array length remains 4, which is a reasonable default (only 3
CCIDs, CCID-2..4, are currently defined).

Signed-off-by: Gerrit Renker <redacted>

Applied to net-next-2.6, thanks Gerrit.