diff options
| author | Florian Westphal <fw@strlen.de> | 2019-01-04 14:17:05 +0100 |
|---|---|---|
| committer | Steffen Klassert <steffen.klassert@secunet.com> | 2019-01-09 13:58:23 +0100 |
| commit | 12750abad517a991c4568969bc748db302ab52cd (patch) | |
| tree | d5a896fc8490185aee1e73bc7ab13c58d8059c92 /net/xfrm | |
| parent | selftests: xfrm: alter htresh to trigger move of policies to hash table (diff) | |
| download | linux-12750abad517a991c4568969bc748db302ab52cd.tar.xz linux-12750abad517a991c4568969bc748db302ab52cd.zip | |
xfrm: policy: fix infinite loop when merging src-nodes
With very small change to test script we can trigger softlockup due to
bogus assignment of 'p' (policy to be examined) on restart.
Previously the two to-be-merged nodes had same address/prefixlength pair,
so no erase/reinsert was necessary, we only had to append the list from
node a to b.
If prefix lengths are different, the node has to be deleted and re-inserted
into the tree, with the updated prefix length. This was broken; due to
bogus update to 'p' this loops forever.
Add a 'restart' label and use that instead.
While at it, don't perform the unneeded reinserts of the policies that
are already sorted into the 'new' node.
A previous patch in this series made xfrm_policy_inexact_list_reinsert()
use the relative position indicator to sort policies according to age in
case priorities are identical.
Fixes: 6ac098b2a9d30 ("xfrm: policy: add 2nd-level saddr trees for inexact policies")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Diffstat (limited to 'net/xfrm')
| -rw-r--r-- | net/xfrm/xfrm_policy.c | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index e691683223ee..8cfd75b62396 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -886,12 +886,13 @@ static void xfrm_policy_inexact_node_reinsert(struct net *net, struct rb_root *new, u16 family) { - struct rb_node **p, *parent = NULL; struct xfrm_pol_inexact_node *node; + struct rb_node **p, *parent; /* we should not have another subtree here */ WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); - +restart: + parent = NULL; p = &new->rb_node; while (*p) { u8 prefixlen; @@ -911,12 +912,11 @@ static void xfrm_policy_inexact_node_reinsert(struct net *net, } else { struct xfrm_policy *tmp; - hlist_for_each_entry(tmp, &node->hhead, bydst) - tmp->bydst_reinsert = true; - hlist_for_each_entry(tmp, &n->hhead, bydst) + hlist_for_each_entry(tmp, &n->hhead, bydst) { tmp->bydst_reinsert = true; + hlist_del_rcu(&tmp->bydst); + } - INIT_HLIST_HEAD(&node->hhead); xfrm_policy_inexact_list_reinsert(net, node, family); if (node->prefixlen == n->prefixlen) { @@ -928,8 +928,7 @@ static void xfrm_policy_inexact_node_reinsert(struct net *net, kfree_rcu(n, rcu); n = node; n->prefixlen = prefixlen; - *p = new->rb_node; - parent = NULL; + goto restart; } } |