This is a note to let you know that I've just added the patch titled netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction to the 5.4-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-skip-sync-gc-for-new-elements-in-this-transaction.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From stable-owner@xxxxxxxxxxxxxxx Tue Nov 21 12:13:57 2023 From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Date: Tue, 21 Nov 2023 13:13:24 +0100 Subject: netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction To: netfilter-devel@xxxxxxxxxxxxxxx Cc: gregkh@xxxxxxxxxxxxxxxxxxx, sashal@xxxxxxxxxx, stable@xxxxxxxxxxxxxxx Message-ID: <20231121121333.294238-18-pablo@xxxxxxxxxxxxx> From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> commit 2ee52ae94baabf7ee09cf2a8d854b990dac5d0e4 upstream. New elements in this transaction might expired before such transaction ends. Skip sync GC for such elements otherwise commit path might walk over an already released object. Once transaction is finished, async GC will collect such expired element. Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API") Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/nft_set_rbtree.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/net/netfilter/nft_set_rbtree.c +++ b/net/netfilter/nft_set_rbtree.c @@ -314,6 +314,7 @@ static int __nft_rbtree_insert(const str struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL; struct rb_node *node, *next, *parent, **p, *first = NULL; struct nft_rbtree *priv = nft_set_priv(set); + u8 cur_genmask = nft_genmask_cur(net); u8 genmask = nft_genmask_next(net); int d, err; @@ -359,8 +360,11 @@ static int __nft_rbtree_insert(const str if (!nft_set_elem_active(&rbe->ext, genmask)) continue; - /* perform garbage collection to avoid bogus overlap reports. */ - if (nft_set_elem_expired(&rbe->ext)) { + /* perform garbage collection to avoid bogus overlap reports + * but skip new elements in this transaction. + */ + if (nft_set_elem_expired(&rbe->ext) && + nft_set_elem_active(&rbe->ext, cur_genmask)) { err = nft_rbtree_gc_elem(set, priv, rbe, genmask); if (err < 0) return err; Patches currently in stable-queue which might be from stable-owner@xxxxxxxxxxxxxxx are queue-5.4/netfilter-nf_tables-fix-memleak-when-more-than-255-elements-expired.patch queue-5.4/netfilter-nft_set_rbtree-fix-overlap-expiration-walk.patch queue-5.4/netfilter-nf_tables-use-correct-lock-to-protect-gc_list.patch queue-5.4/netfilter-nf_tables-disable-toggling-dormant-table-state-more-than-once.patch queue-5.4/netfilter-nf_tables-gc-transaction-race-with-netns-dismantle.patch queue-5.4/netfilter-nf_tables-drop-map-element-references-from-preparation-phase.patch queue-5.4/netfilter-nf_tables-fix-gc-transaction-races-with-netns-and-netlink-event-exit-path.patch queue-5.4/netfilter-nf_tables-don-t-skip-expired-elements-during-walk.patch queue-5.4/netfilter-nf_tables-remove-busy-mark-and-gc-batch-api.patch queue-5.4/netfilter-nf_tables-gc-transaction-race-with-abort-path.patch queue-5.4/netfilter-nf_tables-unregister-flowtable-hooks-on-netns-exit.patch queue-5.4/netfilter-nft_set_rbtree-switch-to-node-list-walk-for-overlap-detection.patch queue-5.4/netfilter-nf_tables-adapt-set-backend-to-use-gc-transaction-api.patch queue-5.4/netfilter-nftables-rename-set-element-data-activation-deactivation-functions.patch queue-5.4/netfilter-nft_set_rbtree-skip-sync-gc-for-new-elements-in-this-transaction.patch queue-5.4/netfilter-nf_tables-pass-context-to-nft_set_destroy.patch queue-5.4/netfilter-nf_tables-bogus-ebusy-when-deleting-flowtable-after-flush-for-5.4.patch queue-5.4/netfilter-nft_set_hash-try-later-when-gc-hits-eagain-on-iteration.patch queue-5.4/netfilter-nf_tables-defer-gc-run-if-previous-batch-is-still-pending.patch queue-5.4/netfilter-nft_set_rbtree-use-read-spinlock-to-avoid-datapath-contention.patch queue-5.4/netfilter-nf_tables-double-hook-unregistration-in-netns-path.patch queue-5.4/netfilter-nftables-update-table-flags-from-the-commit-phase.patch queue-5.4/netfilter-nft_set_hash-mark-set-element-as-dead-when-deleting-from-packet-path.patch queue-5.4/netfilter-nf_tables-gc-transaction-api-to-avoid-race-with-control-plane.patch queue-5.4/netfilter-nf_tables-fix-table-flag-updates.patch queue-5.4/netfilter-nft_set_rbtree-fix-null-deref-on-element-insertion.patch