From 9ecf07a1d8f70f72ec99a0f102c8aa24609d84f4 Mon Sep 17 00:00:00 2001 From: Mathias Krause <minipli@googlemail.com> Date: Sat, 12 Jul 2014 22:36:44 +0200 Subject: [PATCH] neigh: sysctl - simplify address calculation of gc_* variables The code in neigh_sysctl_register() relies on a specific layout of struct neigh_table, namely that the 'gc_*' variables are directly following the 'parms' member in a specific order. The code, though, expresses this in the most ugly way. Get rid of the ugly casts and use the 'tbl' pointer to get a handle to the table. This way we can refer to the 'gc_*' variables directly. Similarly seen in the grsecurity patch, written by Brad Spengler. Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Brad Spengler <spender@grsecurity.net> Signed-off-by: David S. Miller <davem@davemloft.net> --- include/net/neighbour.h | 1 - net/core/neighbour.c | 9 +++++---- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/include/net/neighbour.h b/include/net/neighbour.h index 7277caf3743d..47f425464f84 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -203,7 +203,6 @@ struct neigh_table { void (*proxy_redo)(struct sk_buff *skb); char *id; struct neigh_parms parms; - /* HACK. gc_* should follow parms without a gap! */ int gc_interval; int gc_thresh1; int gc_thresh2; diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 32d872eec7f5..559890b0f0a2 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -3059,11 +3059,12 @@ int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p, memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0, sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL])); } else { + struct neigh_table *tbl = p->tbl; dev_name_source = "default"; - t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = (int *)(p + 1); - t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = (int *)(p + 1) + 1; - t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = (int *)(p + 1) + 2; - t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = (int *)(p + 1) + 3; + t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval; + t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1; + t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2; + t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3; } if (handler) { -- 2.30.9