This is a note to let you know that I've just added the patch titled netfilter: nft_set_rbtree: handle element re-addition after deletion to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-nft_set_rbtree-handle-element-re-addition-after-deletion.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From d2df92e98a34a5619dadd29c6291113c009181e7 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Date: Sun, 21 May 2017 00:37:10 +0200 Subject: netfilter: nft_set_rbtree: handle element re-addition after deletion 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; } } } Patches currently in stable-queue which might be from pablo@xxxxxxxxxxxxx are queue-4.11/netfilter-nft_set_rbtree-handle-element-re-addition-after-deletion.patch