netfilter: xt_physdev fixes

1) physdev_mt() incorrectly assumes nulldevname[] is aligned on an int

2) It also uses word comparisons, while it could use long word ones.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/net/netfilter/xt_physdev.c b/net/netfilter/xt_physdev.c
index 1bcdfc12cf59827028c682d898ea15f45df3e6a6..4b13ef7ce14575534e6012a31d8964f4e51e7d5d 100644 (file)
--- a/net/netfilter/xt_physdev.c
+++ b/net/netfilter/xt_physdev.c
@@ -24,9 +24,9 @@ static bool
 physdev_mt(const struct sk_buff *skb, const struct xt_match_param *par)
 {
        int i;
-       static const char nulldevname[IFNAMSIZ];
+       static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
        const struct xt_physdev_info *info = par->matchinfo;
-       bool ret;
+       unsigned long ret;
        const char *indev, *outdev;
        const struct nf_bridge_info *nf_bridge;
 
@@ -68,10 +68,10 @@ physdev_mt(const struct sk_buff *skb, const struct xt_match_param *par)
        if (!(info->bitmask & XT_PHYSDEV_OP_IN))
                goto match_outdev;
        indev = nf_bridge->physindev ? nf_bridge->physindev->name : nulldevname;
-       for (i = 0, ret = false; i < IFNAMSIZ/sizeof(unsigned int); i++) {
-               ret |= (((const unsigned int *)indev)[i]
-                       ^ ((const unsigned int *)info->physindev)[i])
-                       & ((const unsigned int *)info->in_mask)[i];
+       for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
+               ret |= (((const unsigned long *)indev)[i]
+                       ^ ((const unsigned long *)info->physindev)[i])
+                       & ((const unsigned long *)info->in_mask)[i];
        }
 
        if (!ret ^ !(info->invert & XT_PHYSDEV_OP_IN))
@@ -82,13 +82,12 @@ match_outdev:
                return true;
        outdev = nf_bridge->physoutdev ?
                 nf_bridge->physoutdev->name : nulldevname;
-       for (i = 0, ret = false; i < IFNAMSIZ/sizeof(unsigned int); i++) {
-               ret |= (((const unsigned int *)outdev)[i]
-                       ^ ((const unsigned int *)info->physoutdev)[i])
-                       & ((const unsigned int *)info->out_mask)[i];
+       for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
+               ret |= (((const unsigned long *)outdev)[i]
+                       ^ ((const unsigned long *)info->physoutdev)[i])
+                       & ((const unsigned long *)info->out_mask)[i];
        }
-
-       return ret ^ !(info->invert & XT_PHYSDEV_OP_OUT);
+       return (!!ret ^ !(info->invert & XT_PHYSDEV_OP_OUT));
 }
 
 static bool physdev_mt_check(const struct xt_mtchk_param *par)