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authorDavid S. Miller <davem@davemloft.net>2020-09-22 16:45:34 -0700
committerDavid S. Miller <davem@davemloft.net>2020-09-22 16:45:34 -0700
commit3ab0a7a0c349a1d7beb2bb371a62669d1528269d (patch)
treed2ae17c3bfc829ce0c747ad97021cd4bc8fb11dc /net/batman-adv/bridge_loop_avoidance.c
parent92ec804f3dbf0d986f8e10850bfff14f316d7aaf (diff)
parent805c6d3c19210c90c109107d189744e960eae025 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Two minor conflicts: 1) net/ipv4/route.c, adding a new local variable while moving another local variable and removing it's initial assignment. 2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes. One pretty prints the port mode differently, whilst another changes the driver to try and obtain the port mode from the port node rather than the switch node. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/batman-adv/bridge_loop_avoidance.c')
-rw-r--r--net/batman-adv/bridge_loop_avoidance.c145
1 files changed, 117 insertions, 28 deletions
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index ab6cec3c7586..ba0027d1f2df 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -25,6 +25,7 @@
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
+#include <linux/preempt.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
@@ -83,11 +84,12 @@ static inline u32 batadv_choose_claim(const void *data, u32 size)
*/
static inline u32 batadv_choose_backbone_gw(const void *data, u32 size)
{
- const struct batadv_bla_claim *claim = (struct batadv_bla_claim *)data;
+ const struct batadv_bla_backbone_gw *gw;
u32 hash = 0;
- hash = jhash(&claim->addr, sizeof(claim->addr), hash);
- hash = jhash(&claim->vid, sizeof(claim->vid), hash);
+ gw = (struct batadv_bla_backbone_gw *)data;
+ hash = jhash(&gw->orig, sizeof(gw->orig), hash);
+ hash = jhash(&gw->vid, sizeof(gw->vid), hash);
return hash % size;
}
@@ -1579,13 +1581,16 @@ int batadv_bla_init(struct batadv_priv *bat_priv)
}
/**
- * batadv_bla_check_bcast_duplist() - Check if a frame is in the broadcast dup.
+ * batadv_bla_check_duplist() - Check if a frame is in the broadcast dup.
* @bat_priv: the bat priv with all the soft interface information
- * @skb: contains the bcast_packet to be checked
+ * @skb: contains the multicast packet to be checked
+ * @payload_ptr: pointer to position inside the head buffer of the skb
+ * marking the start of the data to be CRC'ed
+ * @orig: originator mac address, NULL if unknown
*
- * check if it is on our broadcast list. Another gateway might
- * have sent the same packet because it is connected to the same backbone,
- * so we have to remove this duplicate.
+ * Check if it is on our broadcast list. Another gateway might have sent the
+ * same packet because it is connected to the same backbone, so we have to
+ * remove this duplicate.
*
* This is performed by checking the CRC, which will tell us
* with a good chance that it is the same packet. If it is furthermore
@@ -1594,19 +1599,17 @@ int batadv_bla_init(struct batadv_priv *bat_priv)
*
* Return: true if a packet is in the duplicate list, false otherwise.
*/
-bool batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
- struct sk_buff *skb)
+static bool batadv_bla_check_duplist(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, u8 *payload_ptr,
+ const u8 *orig)
{
- int i, curr;
- __be32 crc;
- struct batadv_bcast_packet *bcast_packet;
struct batadv_bcast_duplist_entry *entry;
bool ret = false;
-
- bcast_packet = (struct batadv_bcast_packet *)skb->data;
+ int i, curr;
+ __be32 crc;
/* calculate the crc ... */
- crc = batadv_skb_crc32(skb, (u8 *)(bcast_packet + 1));
+ crc = batadv_skb_crc32(skb, payload_ptr);
spin_lock_bh(&bat_priv->bla.bcast_duplist_lock);
@@ -1625,8 +1628,21 @@ bool batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
if (entry->crc != crc)
continue;
- if (batadv_compare_eth(entry->orig, bcast_packet->orig))
- continue;
+ /* are the originators both known and not anonymous? */
+ if (orig && !is_zero_ether_addr(orig) &&
+ !is_zero_ether_addr(entry->orig)) {
+ /* If known, check if the new frame came from
+ * the same originator:
+ * We are safe to take identical frames from the
+ * same orig, if known, as multiplications in
+ * the mesh are detected via the (orig, seqno) pair.
+ * So we can be a bit more liberal here and allow
+ * identical frames from the same orig which the source
+ * host might have sent multiple times on purpose.
+ */
+ if (batadv_compare_eth(entry->orig, orig))
+ continue;
+ }
/* this entry seems to match: same crc, not too old,
* and from another gw. therefore return true to forbid it.
@@ -1642,7 +1658,14 @@ bool batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
entry = &bat_priv->bla.bcast_duplist[curr];
entry->crc = crc;
entry->entrytime = jiffies;
- ether_addr_copy(entry->orig, bcast_packet->orig);
+
+ /* known originator */
+ if (orig)
+ ether_addr_copy(entry->orig, orig);
+ /* anonymous originator */
+ else
+ eth_zero_addr(entry->orig);
+
bat_priv->bla.bcast_duplist_curr = curr;
out:
@@ -1652,6 +1675,48 @@ out:
}
/**
+ * batadv_bla_check_ucast_duplist() - Check if a frame is in the broadcast dup.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: contains the multicast packet to be checked, decapsulated from a
+ * unicast_packet
+ *
+ * Check if it is on our broadcast list. Another gateway might have sent the
+ * same packet because it is connected to the same backbone, so we have to
+ * remove this duplicate.
+ *
+ * Return: true if a packet is in the duplicate list, false otherwise.
+ */
+static bool batadv_bla_check_ucast_duplist(struct batadv_priv *bat_priv,
+ struct sk_buff *skb)
+{
+ return batadv_bla_check_duplist(bat_priv, skb, (u8 *)skb->data, NULL);
+}
+
+/**
+ * batadv_bla_check_bcast_duplist() - Check if a frame is in the broadcast dup.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: contains the bcast_packet to be checked
+ *
+ * Check if it is on our broadcast list. Another gateway might have sent the
+ * same packet because it is connected to the same backbone, so we have to
+ * remove this duplicate.
+ *
+ * Return: true if a packet is in the duplicate list, false otherwise.
+ */
+bool batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
+ struct sk_buff *skb)
+{
+ struct batadv_bcast_packet *bcast_packet;
+ u8 *payload_ptr;
+
+ bcast_packet = (struct batadv_bcast_packet *)skb->data;
+ payload_ptr = (u8 *)(bcast_packet + 1);
+
+ return batadv_bla_check_duplist(bat_priv, skb, payload_ptr,
+ bcast_packet->orig);
+}
+
+/**
* batadv_bla_is_backbone_gw_orig() - Check if the originator is a gateway for
* the VLAN identified by vid.
* @bat_priv: the bat priv with all the soft interface information
@@ -1812,7 +1877,7 @@ batadv_bla_loopdetect_check(struct batadv_priv *bat_priv, struct sk_buff *skb,
* @bat_priv: the bat priv with all the soft interface information
* @skb: the frame to be checked
* @vid: the VLAN ID of the frame
- * @is_bcast: the packet came in a broadcast packet type.
+ * @packet_type: the batman packet type this frame came in
*
* batadv_bla_rx avoidance checks if:
* * we have to race for a claim
@@ -1824,7 +1889,7 @@ batadv_bla_loopdetect_check(struct batadv_priv *bat_priv, struct sk_buff *skb,
* further process the skb.
*/
bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb,
- unsigned short vid, bool is_bcast)
+ unsigned short vid, int packet_type)
{
struct batadv_bla_backbone_gw *backbone_gw;
struct ethhdr *ethhdr;
@@ -1846,9 +1911,32 @@ bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb,
goto handled;
if (unlikely(atomic_read(&bat_priv->bla.num_requests)))
- /* don't allow broadcasts while requests are in flight */
- if (is_multicast_ether_addr(ethhdr->h_dest) && is_bcast)
- goto handled;
+ /* don't allow multicast packets while requests are in flight */
+ if (is_multicast_ether_addr(ethhdr->h_dest))
+ /* Both broadcast flooding or multicast-via-unicasts
+ * delivery might send to multiple backbone gateways
+ * sharing the same LAN and therefore need to coordinate
+ * which backbone gateway forwards into the LAN,
+ * by claiming the payload source address.
+ *
+ * Broadcast flooding and multicast-via-unicasts
+ * delivery use the following two batman packet types.
+ * Note: explicitly exclude BATADV_UNICAST_4ADDR,
+ * as the DHCP gateway feature will send explicitly
+ * to only one BLA gateway, so the claiming process
+ * should be avoided there.
+ */
+ if (packet_type == BATADV_BCAST ||
+ packet_type == BATADV_UNICAST)
+ goto handled;
+
+ /* potential duplicates from foreign BLA backbone gateways via
+ * multicast-in-unicast packets
+ */
+ if (is_multicast_ether_addr(ethhdr->h_dest) &&
+ packet_type == BATADV_UNICAST &&
+ batadv_bla_check_ucast_duplist(bat_priv, skb))
+ goto handled;
ether_addr_copy(search_claim.addr, ethhdr->h_source);
search_claim.vid = vid;
@@ -1883,13 +1971,14 @@ bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb,
goto allow;
}
- /* if it is a broadcast ... */
- if (is_multicast_ether_addr(ethhdr->h_dest) && is_bcast) {
+ /* if it is a multicast ... */
+ if (is_multicast_ether_addr(ethhdr->h_dest) &&
+ (packet_type == BATADV_BCAST || packet_type == BATADV_UNICAST)) {
/* ... drop it. the responsible gateway is in charge.
*
- * We need to check is_bcast because with the gateway
+ * We need to check packet type because with the gateway
* feature, broadcasts (like DHCP requests) may be sent
- * using a unicast packet type.
+ * using a unicast 4 address packet type. See comment above.
*/
goto handled;
} else {