On Tue, 1 Feb 2011, David Miller wrote: > From: Julia Lawall <julia@xxxxxxx> > Date: Fri, 28 Jan 2011 16:43:40 +0100 (CET) > > > nlmsg_cancel can accept NULL as its second argument, so for similarity, > > this patch extends genlmsg_cancel to be able to accept a NULL second > > argument as well. > > > > Signed-off-by: Julia Lawall <julia@xxxxxxx> > > I did a scan of all of the cases where this interface is used, and > I cannot find a situation where this capability would even be useful. > > The use pattern is always: > > hdr = genlmsg_put(skb, ...); > if (!hdr) > goto out; > > NLA_PUT_*(); > NLA_PUT_*(); > .... > > return genlmsg_end(skb, hdr); > > nla_put_failure: > genlmsg_cancel(skb, hdr); > out: > return -EWHATEVER; > > Always, hdr will be non-NULL. > > We have to allocate the header first, then put the netlink > attributes. > > Looking over users of nlmsg_cancel(), the situation seems to > match identically. > > Therefore, it seems to me that it makes more sense to remove > the NULL check from nlmsg_cancel() than to add the NULL check > to genlmsg_cancel(). I saw lots of cases that could be done like this, but were not; they had goto nla_put_failure instead. I will double check. julia -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
