diff options
| author | Antoine Tenart <atenart@kernel.org> | 2025-11-26 11:26:25 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-11-27 17:48:57 -0800 |
| commit | 1f73a56f986005f0bc64ed23873930e2ee4f5911 (patch) | |
| tree | 4704661ea763f34a46ed48cbaf06608f57fc1486 /drivers | |
| parent | 1e43ebcd5152b3e681a334cc6542fb21770c3a2e (diff) | |
| download | net-1f73a56f986005f0bc64ed23873930e2ee4f5911.tar.gz | |
net: vxlan: prevent NULL deref in vxlan_xmit_one
Neither sock4 nor sock6 pointers are guaranteed to be non-NULL in
vxlan_xmit_one, e.g. if the iface is brought down. This can lead to the
following NULL dereference:
BUG: kernel NULL pointer dereference, address: 0000000000000010
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:vxlan_xmit_one+0xbb3/0x1580
Call Trace:
vxlan_xmit+0x429/0x610
dev_hard_start_xmit+0x55/0xa0
__dev_queue_xmit+0x6d0/0x7f0
ip_finish_output2+0x24b/0x590
ip_output+0x63/0x110
Mentioned commits changed the code path in vxlan_xmit_one and as a side
effect the sock4/6 pointer validity checks in vxlan(6)_get_route were
lost. Fix this by adding back checks.
Since both commits being fixed were released in the same version (v6.7)
and are strongly related, bundle the fixes in a single commit.
Reported-by: Liang Li <liali@redhat.com>
Fixes: 6f19b2c136d9 ("vxlan: use generic function for tunnel IPv4 route lookup")
Fixes: 2aceb896ee18 ("vxlan: use generic function for tunnel IPv6 route lookup")
Cc: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20251126102627.74223-1-atenart@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/vxlan/vxlan_core.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c index a5c55e7e4d795f..e957aa12a8a44a 100644 --- a/drivers/net/vxlan/vxlan_core.c +++ b/drivers/net/vxlan/vxlan_core.c @@ -2349,7 +2349,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, int addr_family; __u8 tos, ttl; int ifindex; - int err; + int err = 0; u32 flags = vxlan->cfg.flags; bool use_cache; bool udp_sum = false; @@ -2454,12 +2454,18 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, rcu_read_lock(); if (addr_family == AF_INET) { - struct vxlan_sock *sock4 = rcu_dereference(vxlan->vn4_sock); + struct vxlan_sock *sock4; u16 ipcb_flags = 0; struct rtable *rt; __be16 df = 0; __be32 saddr; + sock4 = rcu_dereference(vxlan->vn4_sock); + if (unlikely(!sock4)) { + reason = SKB_DROP_REASON_DEV_READY; + goto tx_error; + } + if (!ifindex) ifindex = sock4->sock->sk->sk_bound_dev_if; @@ -2534,10 +2540,16 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, ipcb_flags); #if IS_ENABLED(CONFIG_IPV6) } else { - struct vxlan_sock *sock6 = rcu_dereference(vxlan->vn6_sock); + struct vxlan_sock *sock6; struct in6_addr saddr; u16 ip6cb_flags = 0; + sock6 = rcu_dereference(vxlan->vn6_sock); + if (unlikely(!sock6)) { + reason = SKB_DROP_REASON_DEV_READY; + goto tx_error; + } + if (!ifindex) ifindex = sock6->sock->sk->sk_bound_dev_if; |