This is a note to let you know that I've just added the patch titled netfilter: nf_tables: GC transaction race with netns dismantle 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-nf_tables-gc-transaction-race-with-netns-dismantle.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 12:13:55 2023 From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Date: Tue, 21 Nov 2023 13:13:20 +0100 Subject: netfilter: nf_tables: GC transaction race with netns dismantle To: netfilter-devel@xxxxxxxxxxxxxxx Cc: gregkh@xxxxxxxxxxxxxxxxxxx, sashal@xxxxxxxxxx, stable@xxxxxxxxxxxxxxx Message-ID: <20231121121333.294238-14-pablo@xxxxxxxxxxxxx> From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> commit 02c6c24402bf1c1e986899c14ba22a10b510916b upstream. Use maybe_get_net() since GC workqueue might race with netns exit path. Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane") Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/nf_tables_api.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7052,9 +7052,14 @@ struct nft_trans_gc *nft_trans_gc_alloc( if (!trans) return NULL; + trans->net = maybe_get_net(net); + if (!trans->net) { + kfree(trans); + return NULL; + } + refcount_inc(&set->refs); trans->set = set; - trans->net = get_net(net); trans->seq = gc_seq; return trans; 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