4.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> commit d2df92e98a34a5619dadd29c6291113c009181e7 upstream. The existing code selects no next branch to be inspected when re-inserting an inactive element into the rb-tree, looping endlessly. This patch restricts the check for active elements to the EEXIST case only. Fixes: e701001e7cbe ("netfilter: nft_rbtree: allow adjacent intervals with dynamic updates") Reported-by: Wolfgang Bumiller <w.bumiller@xxxxxxxxxxx> Tested-by: Wolfgang Bumiller <w.bumiller@xxxxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/nft_set_rbtree.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) --- a/net/netfilter/nft_set_rbtree.c +++ b/net/netfilter/nft_set_rbtree.c @@ -117,17 +117,17 @@ static int __nft_rbtree_insert(const str else if (d > 0) p = &parent->rb_right; else { - if (nft_set_elem_active(&rbe->ext, genmask)) { - if (nft_rbtree_interval_end(rbe) && - !nft_rbtree_interval_end(new)) - p = &parent->rb_left; - else if (!nft_rbtree_interval_end(rbe) && - nft_rbtree_interval_end(new)) - p = &parent->rb_right; - else { - *ext = &rbe->ext; - return -EEXIST; - } + if (nft_rbtree_interval_end(rbe) && + !nft_rbtree_interval_end(new)) { + p = &parent->rb_left; + } else if (!nft_rbtree_interval_end(rbe) && + nft_rbtree_interval_end(new)) { + p = &parent->rb_right; + } else if (nft_set_elem_active(&rbe->ext, genmask)) { + *ext = &rbe->ext; + return -EEXIST; + } else { + p = &parent->rb_left; } } }