[XFRM]: Hash xfrm_state objects by source address too.

The source address is always non-prefixed so we should use
it to help give entropy to the bydst hash.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/xfrm/xfrm_state.c

@@ -65,26 +65,40 @@ static inline unsigned int __xfrm6_addr_hash(xfrm_address_t *addr)
 	return ntohl(addr->a6[2]^addr->a6[3]);
 }
 
-static inline unsigned int __xfrm_dst_hash(xfrm_address_t *addr,
+static inline unsigned int __xfrm4_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
+{
+	return ntohl(daddr->a4 ^ saddr->a4);
+}
+
+static inline unsigned int __xfrm6_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
+{
+	return ntohl(daddr->a6[2] ^ daddr->a6[3] ^
+		     saddr->a6[2] ^ saddr->a6[3]);
+}
+
+static inline unsigned int __xfrm_dst_hash(xfrm_address_t *daddr,
+					   xfrm_address_t *saddr,
 					   u32 reqid, unsigned short family,
 					   unsigned int hmask)
 {
 	unsigned int h = family ^ reqid;
 	switch (family) {
 	case AF_INET:
-		h ^= __xfrm4_addr_hash(addr);
+		h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
 		break;
 	case AF_INET6:
-		h ^= __xfrm6_addr_hash(addr);
+		h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
 		break;
 	};
 	return (h ^ (h >> 16)) & hmask;
 }
 
-static inline unsigned int xfrm_dst_hash(xfrm_address_t *addr, u32 reqid,
+static inline unsigned int xfrm_dst_hash(xfrm_address_t *daddr,
+					 xfrm_address_t *saddr,
+					 u32 reqid,
 					 unsigned short family)
 {
-	return __xfrm_dst_hash(addr, reqid, family, xfrm_state_hmask);
+	return __xfrm_dst_hash(daddr, saddr, reqid, family, xfrm_state_hmask);
 }
 
 static inline unsigned __xfrm_src_hash(xfrm_address_t *addr, unsigned short family,
@@ -108,25 +122,25 @@ static inline unsigned xfrm_src_hash(xfrm_address_t *addr, unsigned short family
 }
 
 static inline unsigned int
-__xfrm_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto, unsigned short family,
-		unsigned int hmask)
+__xfrm_spi_hash(xfrm_address_t *daddr, u32 spi, u8 proto,
+		unsigned short family, unsigned int hmask)
 {
 	unsigned int h = spi ^ proto;
 	switch (family) {
 	case AF_INET:
-		h ^= __xfrm4_addr_hash(addr);
+		h ^= __xfrm4_addr_hash(daddr);
 		break;
 	case AF_INET6:
-		h ^= __xfrm6_addr_hash(addr);
+		h ^= __xfrm6_addr_hash(daddr);
 		break;
 	}
 	return (h ^ (h >> 10) ^ (h >> 20)) & hmask;
 }
 
 static inline unsigned int
-xfrm_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto, unsigned short family)
+xfrm_spi_hash(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family)
 {
-	return __xfrm_spi_hash(addr, spi, proto, family, xfrm_state_hmask);
+	return __xfrm_spi_hash(daddr, spi, proto, family, xfrm_state_hmask);
 }
 
 static struct hlist_head *xfrm_state_hash_alloc(unsigned int sz)
@@ -169,8 +183,9 @@ static void xfrm_hash_transfer(struct hlist_head *list,
 	hlist_for_each_entry_safe(x, entry, tmp, list, bydst) {
 		unsigned int h;
 
-		h = __xfrm_dst_hash(&x->id.daddr, x->props.reqid,
-				    x->props.family, nhashmask);
+		h = __xfrm_dst_hash(&x->id.daddr, &x->props.saddr,
+				    x->props.reqid, x->props.family,
+				    nhashmask);
 		hlist_add_head(&x->bydst, ndsttable+h);
 
 		h = __xfrm_src_hash(&x->props.saddr, x->props.family,
@@ -587,7 +602,7 @@ xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
 		struct xfrm_policy *pol, int *err,
 		unsigned short family)
 {
-	unsigned int h = xfrm_dst_hash(daddr, tmpl->reqid, family);
+	unsigned int h = xfrm_dst_hash(daddr, saddr, tmpl->reqid, family);
 	struct hlist_node *entry;
 	struct xfrm_state *x, *x0;
 	int acquire_in_progress = 0;
@@ -696,7 +711,8 @@ static void __xfrm_state_insert(struct xfrm_state *x)
 
 	x->genid = ++xfrm_state_genid;
 
-	h = xfrm_dst_hash(&x->id.daddr, x->props.reqid, x->props.family);
+	h = xfrm_dst_hash(&x->id.daddr, &x->props.saddr,
+			  x->props.reqid, x->props.family);
 	hlist_add_head(&x->bydst, xfrm_state_bydst+h);
 
 	h = xfrm_src_hash(&x->props.saddr, x->props.family);
@@ -732,11 +748,12 @@ static void __xfrm_state_bump_genids(struct xfrm_state *xnew)
 	struct hlist_node *entry;
 	unsigned int h;
 
-	h = xfrm_dst_hash(&xnew->id.daddr, reqid, family);
+	h = xfrm_dst_hash(&xnew->id.daddr, &xnew->props.saddr, reqid, family);
 	hlist_for_each_entry(x, entry, xfrm_state_bydst+h, bydst) {
 		if (x->props.family	== family &&
 		    x->props.reqid	== reqid &&
-		    !xfrm_addr_cmp(&x->id.daddr, &xnew->id.daddr, family))
+		    !xfrm_addr_cmp(&x->id.daddr, &xnew->id.daddr, family) &&
+		    !xfrm_addr_cmp(&x->props.saddr, &xnew->props.saddr, family))
 			x->genid = xfrm_state_genid;
 	}
 }
@@ -753,7 +770,7 @@ EXPORT_SYMBOL(xfrm_state_insert);
 /* xfrm_state_lock is held */
 static struct xfrm_state *__find_acq_core(unsigned short family, u8 mode, u32 reqid, u8 proto, xfrm_address_t *daddr, xfrm_address_t *saddr, int create)
 {
-	unsigned int h = xfrm_dst_hash(daddr, reqid, family);
+	unsigned int h = xfrm_dst_hash(daddr, saddr, reqid, family);
 	struct hlist_node *entry;
 	struct xfrm_state *x;