| 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 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20110610165656.GA25677@minipsycho.redhat.com>
Date: Fri, 10 Jun 2011 18:56:58 +0200
From: Jiri Pirko <jpirko@...hat.com>
To: Changli Gao <xiaosuo@...il.com>
Cc: David Miller <davem@...emloft.net>, pratnakarlx@...il.com,
ebiederm@...ssion.com, shemminger@...ux-foundation.org,
greearb@...delatech.com, nicolas.2p.debian@...il.com,
netdev@...r.kernel.org, kaber@...sh.net, fubar@...ibm.com,
eric.dumazet@...il.com, andy@...yhouse.net, jesse@...ira.com
Subject: Re: [PATCH v3] vlan: Fix the ingress VLAN_FLAG_REORDER_HDR check
This time heavily based on Eric's V2. mac_len is reset at appropriate
places. Also skb->data is adjusted to point to beginning of mac header
before calling vlan_insert_tag.
Please review (fingers crossed).
Subject: [patch net-2.6 v2.1] vlan: Fix the ingress VLAN_FLAG_REORDER_HDR check
Testing of VLAN_FLAG_REORDER_HDR does not belong in vlan_untag
but rather in vlan_do_receive. Otherwise the vlan header
will not be properly put on the packet in the case of
vlan header accelleration.
As we remove the check from vlan_check_reorder_header
rename it vlan_reorder_header to keep the naming clean.
Fix up the skb->pkt_type early so we don't look at the packet
after adding the vlan tag, which guarantees we don't goof
and look at the wrong field.
Use a simple if statement instead of a complicated switch
statement to decided that we need to increment rx_stats
for a multicast packet.
Hopefully at somepoint we will just declare the case where
VLAN_FLAG_REORDER_HDR is cleared as unsupported and remove
the code. Until then this keeps it working correctly.
Signed-off-by: Eric W. Biederman <ebiederm@...ssion.com>
Signed-off-by: Jiri Pirko <jpirko@...hat.com>
---
include/linux/if_vlan.h | 25 +++++++++++++++++--
include/linux/skbuff.h | 5 ++++
net/8021q/vlan_core.c | 60 +++++++++++++++++++++++++---------------------
net/core/dev.c | 2 +-
4 files changed, 61 insertions(+), 31 deletions(-)
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index dc01681..affa273 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -225,7 +225,7 @@ static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
}
/**
- * __vlan_put_tag - regular VLAN tag inserting
+ * vlan_insert_tag - regular VLAN tag inserting
* @skb: skbuff to tag
* @vlan_tci: VLAN TCI to insert
*
@@ -234,8 +234,10 @@ static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
*
* Following the skb_unshare() example, in case of error, the calling function
* doesn't have to worry about freeing the original skb.
+ *
+ * Does not change skb->protocol so this function can be used during receive.
*/
-static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
+static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb, u16 vlan_tci)
{
struct vlan_ethhdr *veth;
@@ -255,8 +257,25 @@ static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
/* now, the TCI */
veth->h_vlan_TCI = htons(vlan_tci);
- skb->protocol = htons(ETH_P_8021Q);
+ return skb;
+}
+/**
+ * __vlan_put_tag - regular VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_tci: VLAN TCI to insert
+ *
+ * Inserts the VLAN tag into @skb as part of the payload
+ * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ */
+static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
+{
+ skb = vlan_insert_tag(skb, vlan_tci);
+ if (skb)
+ skb->protocol = htons(ETH_P_8021Q);
return skb;
}
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index e8b78ce..c0a4f3a 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1256,6 +1256,11 @@ static inline void skb_reserve(struct sk_buff *skb, int len)
skb->tail += len;
}
+static inline void skb_reset_mac_len(struct sk_buff *skb)
+{
+ skb->mac_len = skb->network_header - skb->mac_header;
+}
+
#ifdef NET_SKBUFF_DATA_USES_OFFSET
static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
{
diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index 41495dc..fcc6846 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -23,6 +23,31 @@ bool vlan_do_receive(struct sk_buff **skbp)
return false;
skb->dev = vlan_dev;
+ if (skb->pkt_type == PACKET_OTHERHOST) {
+ /* Our lower layer thinks this is not local, let's make sure.
+ * This allows the VLAN to have a different MAC than the
+ * underlying device, and still route correctly. */
+ if (!compare_ether_addr(eth_hdr(skb)->h_dest,
+ vlan_dev->dev_addr))
+ skb->pkt_type = PACKET_HOST;
+ }
+
+ if (!(vlan_dev_info(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) {
+ unsigned int offset = skb->data - skb_mac_header(skb);
+
+ /*
+ * vlan_insert_tag expect skb->data pointing to mac header.
+ * So change skb->data before calling it and change back to
+ * original position later
+ */
+ skb_push(skb, offset);
+ skb = *skbp = vlan_insert_tag(skb, skb->vlan_tci);
+ if (!skb)
+ return false;
+ skb_pull(skb, offset + VLAN_HLEN);
+ skb_reset_mac_len(skb);
+ }
+
skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
skb->vlan_tci = 0;
@@ -31,22 +56,8 @@ bool vlan_do_receive(struct sk_buff **skbp)
u64_stats_update_begin(&rx_stats->syncp);
rx_stats->rx_packets++;
rx_stats->rx_bytes += skb->len;
-
- switch (skb->pkt_type) {
- case PACKET_BROADCAST:
- break;
- case PACKET_MULTICAST:
+ if (skb->pkt_type == PACKET_MULTICAST)
rx_stats->rx_multicast++;
- break;
- case PACKET_OTHERHOST:
- /* Our lower layer thinks this is not local, let's make sure.
- * This allows the VLAN to have a different MAC than the
- * underlying device, and still route correctly. */
- if (!compare_ether_addr(eth_hdr(skb)->h_dest,
- vlan_dev->dev_addr))
- skb->pkt_type = PACKET_HOST;
- break;
- }
u64_stats_update_end(&rx_stats->syncp);
return true;
@@ -89,18 +100,13 @@ gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
}
EXPORT_SYMBOL(vlan_gro_frags);
-static struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
+static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
{
- if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
- if (skb_cow(skb, skb_headroom(skb)) < 0)
- skb = NULL;
- if (skb) {
- /* Lifted from Gleb's VLAN code... */
- memmove(skb->data - ETH_HLEN,
- skb->data - VLAN_ETH_HLEN, 12);
- skb->mac_header += VLAN_HLEN;
- }
- }
+ if (skb_cow(skb, skb_headroom(skb)) < 0)
+ return NULL;
+ memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
+ skb->mac_header += VLAN_HLEN;
+ skb_reset_mac_len(skb);
return skb;
}
@@ -161,7 +167,7 @@ struct sk_buff *vlan_untag(struct sk_buff *skb)
skb_pull_rcsum(skb, VLAN_HLEN);
vlan_set_encap_proto(skb, vhdr);
- skb = vlan_check_reorder_header(skb);
+ skb = vlan_reorder_header(skb);
if (unlikely(!skb))
goto err_free;
diff --git a/net/core/dev.c b/net/core/dev.c
index a54c9f8..9c58c1e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3114,7 +3114,7 @@ static int __netif_receive_skb(struct sk_buff *skb)
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
- skb->mac_len = skb->network_header - skb->mac_header;
+ skb_reset_mac_len(skb);
pt_prev = NULL;
--
1.7.5.2
--
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