lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Tue, 13 Nov 2012 10:15:29 +0100
From:	Antonio Quartulli <ordex@...istici.org>
To:	davem@...emloft.net
Cc:	netdev@...r.kernel.org, b.a.t.m.a.n@...ts.open-mesh.org,
	Simon Wunderlich <simon.wunderlich@...03.tu-chemnitz.de>,
	Simon Wunderlich <siwu@....tu-chemnitz.de>,
	Antonio Quartulli <ordex@...istici.org>
Subject: [PATCH 01/11] batman-adv: don't rely on positions in struct for hashing

From: Simon Wunderlich <simon.wunderlich@...03.tu-chemnitz.de>

The hash functions in the bridge loop avoidance code expects the
VLAN vid to be right after the mac address, but this is not guaranteed.

Fix this by explicitly hashing over the right fields of the struct.

Reported-by: Marek Lindner <lindner_marek@...oo.de>
Signed-off-by: Simon Wunderlich <siwu@....tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@...istici.org>
---
 net/batman-adv/bridge_loop_avoidance.c | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 29a5542..decc042 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -37,18 +37,26 @@ static void batadv_bla_periodic_work(struct work_struct *work);
 static void batadv_bla_send_announce(struct batadv_priv *bat_priv,
 				     struct batadv_backbone_gw *backbone_gw);
 
+static inline void hash_bytes(uint32_t *hash, void *data, uint32_t size)
+{
+	const unsigned char *key = data;
+	int i;
+
+	for (i = 0; i < size; i++) {
+		*hash += key[i];
+		*hash += (*hash << 10);
+		*hash ^= (*hash >> 6);
+	}
+}
+
 /* return the index of the claim */
 static inline uint32_t batadv_choose_claim(const void *data, uint32_t size)
 {
-	const unsigned char *key = data;
+	struct batadv_claim *claim = (struct batadv_claim *)data;
 	uint32_t hash = 0;
-	size_t i;
 
-	for (i = 0; i < ETH_ALEN + sizeof(short); i++) {
-		hash += key[i];
-		hash += (hash << 10);
-		hash ^= (hash >> 6);
-	}
+	hash_bytes(&hash, &claim->addr, sizeof(claim->addr));
+	hash_bytes(&hash, &claim->vid, sizeof(claim->vid));
 
 	hash += (hash << 3);
 	hash ^= (hash >> 11);
@@ -61,15 +69,11 @@ static inline uint32_t batadv_choose_claim(const void *data, uint32_t size)
 static inline uint32_t batadv_choose_backbone_gw(const void *data,
 						 uint32_t size)
 {
-	const unsigned char *key = data;
+	struct batadv_claim *claim = (struct batadv_claim *)data;
 	uint32_t hash = 0;
-	size_t i;
 
-	for (i = 0; i < ETH_ALEN + sizeof(short); i++) {
-		hash += key[i];
-		hash += (hash << 10);
-		hash ^= (hash >> 6);
-	}
+	hash_bytes(&hash, &claim->addr, sizeof(claim->addr));
+	hash_bytes(&hash, &claim->vid, sizeof(claim->vid));
 
 	hash += (hash << 3);
 	hash ^= (hash >> 11);
-- 
1.8.0

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists