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>

1 files changed, 11 insertions, 12 deletions

diff --git a/net/netfilter/xt_physdev.c b/net/netfilter/xt_physdev.c
index 1bcdfc12cf59..4b13ef7ce145 100644
--- 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)