diff options
| author | Florian Westphal <fw@strlen.de> | 2026-04-24 16:58:38 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-04-27 19:02:11 -0700 |
| commit | 4438113be604ee67a7bf4f81da6e1cca41332ce4 (patch) | |
| tree | 4591f0f7f2f0fa34629a0a1731d5fe5493945e41 /net | |
| parent | b3b6babf47517fde6b6de2493dea28e8831b9347 (diff) | |
neigh: let neigh_xmit take skb ownership
neigh_xmit always releases the skb, except when no neighbour table is
found. But even the first added user of neigh_xmit (mpls) relied on
neigh_xmit to release the skb (or queue it for tx).
sashiko reported:
If neigh_xmit() is called with an uninitialized neighbor table (for
example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT
and bypasses its internal out_kfree_skb error path. Because the return
value of neigh_xmit() is ignored here, does this leak the SKB?
Assume full ownership and remove the last code path that doesn't
xmit or free skb.
Fixes: 4fd3d7d9e868 ("neigh: Add helper function neigh_xmit")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260424145843.74055-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/neighbour.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 9e12524b67fa..5d9216016507 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -3210,8 +3210,10 @@ int neigh_xmit(int index, struct net_device *dev, rcu_read_lock(); tbl = rcu_dereference(neigh_tables[index]); - if (!tbl) - goto out_unlock; + if (!tbl) { + rcu_read_unlock(); + goto out_kfree_skb; + } if (index == NEIGH_ARP_TABLE) { u32 key = *((u32 *)addr); @@ -3227,7 +3229,6 @@ int neigh_xmit(int index, struct net_device *dev, goto out_kfree_skb; } err = READ_ONCE(neigh->output)(neigh, skb); -out_unlock: rcu_read_unlock(); } else if (index == NEIGH_LINK_TABLE) { @@ -3237,11 +3238,10 @@ out_unlock: goto out_kfree_skb; err = dev_queue_xmit(skb); } -out: return err; out_kfree_skb: kfree_skb(skb); - goto out; + return err; } EXPORT_SYMBOL(neigh_xmit); |