Hi Greg, Sasha,
This batch contains a backport for recent fixes already upstream for 5.10.x, to add them on top of your enqueued patches:
994209ddf4f4 ("netfilter: nf_tables: reject new basechain after table flag update") 24cea9677025 ("netfilter: nf_tables: flush pending destroy work before exit_net release") a45e6889575c ("netfilter: nf_tables: release batch on table validation from abort path") 0d459e2ffb54 ("netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path") 1bc83a019bbe ("netfilter: nf_tables: discard table flag update with pending basechain deletion")
Please, apply, thanks.
Pablo Neira Ayuso (5): netfilter: nf_tables: reject new basechain after table flag update netfilter: nf_tables: flush pending destroy work before exit_net release netfilter: nf_tables: release batch on table validation from abort path netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path netfilter: nf_tables: discard table flag update with pending basechain deletion
net/netfilter/nf_tables_api.c | 51 ++++++++++++++++++++++++++++------- 1 file changed, 41 insertions(+), 10 deletions(-)
commit 994209ddf4f430946f6247616b2e33d179243769 upstream.
When dormant flag is toggled, hooks are disabled in the commit phase by iterating over current chains in table (existing and new).
The following configuration allows for an inconsistent state:
add table x add chain x y { type filter hook input priority 0; } add table x { flags dormant; } add chain x w { type filter hook input priority 1; }
which triggers the following warning when trying to unregister chain w which is already unregistered.
[ 127.322252] WARNING: CPU: 7 PID: 1211 at net/netfilter/core.c:50 1 __nf_unregister_net_hook+0x21a/0x260 [...] [ 127.322519] Call Trace: [ 127.322521] <TASK> [ 127.322524] ? __warn+0x9f/0x1a0 [ 127.322531] ? __nf_unregister_net_hook+0x21a/0x260 [ 127.322537] ? report_bug+0x1b1/0x1e0 [ 127.322545] ? handle_bug+0x3c/0x70 [ 127.322552] ? exc_invalid_op+0x17/0x40 [ 127.322556] ? asm_exc_invalid_op+0x1a/0x20 [ 127.322563] ? kasan_save_free_info+0x3b/0x60 [ 127.322570] ? __nf_unregister_net_hook+0x6a/0x260 [ 127.322577] ? __nf_unregister_net_hook+0x21a/0x260 [ 127.322583] ? __nf_unregister_net_hook+0x6a/0x260 [ 127.322590] ? __nf_tables_unregister_hook+0x8a/0xe0 [nf_tables] [ 127.322655] nft_table_disable+0x75/0xf0 [nf_tables] [ 127.322717] nf_tables_commit+0x2571/0x2620 [nf_tables]
Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org --- net/netfilter/nf_tables_api.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 2d372d5fcbfa..ce7c573ce8cb 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1805,6 +1805,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, struct nft_chain_hook hook; struct nf_hook_ops *ops;
+ if (table->flags & __NFT_TABLE_F_UPDATE) + return -EINVAL; + err = nft_chain_parse_hook(net, nla, &hook, family, true); if (err < 0) return err;
commit 24cea9677025e0de419989ecb692acd4bb34cac2 upstream.
Similar to 2c9f0293280e ("netfilter: nf_tables: flush pending destroy work before netlink notifier") to address a race between exit_net and the destroy workqueue.
The trace below shows an element to be released via destroy workqueue while exit_net path (triggered via module removal) has already released the set that is used in such transaction.
[ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465 [ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ #359 [ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables] [ 1360.547984] Call Trace: [ 1360.547991] <TASK> [ 1360.547998] dump_stack_lvl+0x53/0x70 [ 1360.548014] print_report+0xc4/0x610 [ 1360.548026] ? __virt_addr_valid+0xba/0x160 [ 1360.548040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 1360.548054] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548176] kasan_report+0xae/0xe0 [ 1360.548189] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548312] nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548447] ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables] [ 1360.548577] ? _raw_spin_unlock_irq+0x18/0x30 [ 1360.548591] process_one_work+0x2f1/0x670 [ 1360.548610] worker_thread+0x4d3/0x760 [ 1360.548627] ? __pfx_worker_thread+0x10/0x10 [ 1360.548640] kthread+0x16b/0x1b0 [ 1360.548653] ? __pfx_kthread+0x10/0x10 [ 1360.548665] ret_from_fork+0x2f/0x50 [ 1360.548679] ? __pfx_kthread+0x10/0x10 [ 1360.548690] ret_from_fork_asm+0x1a/0x30 [ 1360.548707] </TASK>
[ 1360.548719] Allocated by task 192061: [ 1360.548726] kasan_save_stack+0x20/0x40 [ 1360.548739] kasan_save_track+0x14/0x30 [ 1360.548750] __kasan_kmalloc+0x8f/0xa0 [ 1360.548760] __kmalloc_node+0x1f1/0x450 [ 1360.548771] nf_tables_newset+0x10c7/0x1b50 [nf_tables] [ 1360.548883] nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink] [ 1360.548909] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink] [ 1360.548927] netlink_unicast+0x367/0x4f0 [ 1360.548935] netlink_sendmsg+0x34b/0x610 [ 1360.548944] ____sys_sendmsg+0x4d4/0x510 [ 1360.548953] ___sys_sendmsg+0xc9/0x120 [ 1360.548961] __sys_sendmsg+0xbe/0x140 [ 1360.548971] do_syscall_64+0x55/0x120 [ 1360.548982] entry_SYSCALL_64_after_hwframe+0x55/0x5d
[ 1360.548994] Freed by task 192222: [ 1360.548999] kasan_save_stack+0x20/0x40 [ 1360.549009] kasan_save_track+0x14/0x30 [ 1360.549019] kasan_save_free_info+0x3b/0x60 [ 1360.549028] poison_slab_object+0x100/0x180 [ 1360.549036] __kasan_slab_free+0x14/0x30 [ 1360.549042] kfree+0xb6/0x260 [ 1360.549049] __nft_release_table+0x473/0x6a0 [nf_tables] [ 1360.549131] nf_tables_exit_net+0x170/0x240 [nf_tables] [ 1360.549221] ops_exit_list+0x50/0xa0 [ 1360.549229] free_exit_list+0x101/0x140 [ 1360.549236] unregister_pernet_operations+0x107/0x160 [ 1360.549245] unregister_pernet_subsys+0x1c/0x30 [ 1360.549254] nf_tables_module_exit+0x43/0x80 [nf_tables] [ 1360.549345] __do_sys_delete_module+0x253/0x370 [ 1360.549352] do_syscall_64+0x55/0x120 [ 1360.549360] entry_SYSCALL_64_after_hwframe+0x55/0x5d
(gdb) list *__nft_release_table+0x473 0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354). 11349 list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) { 11350 list_del(&flowtable->list); 11351 nft_use_dec(&table->use); 11352 nf_tables_flowtable_destroy(flowtable); 11353 } 11354 list_for_each_entry_safe(set, ns, &table->sets, list) { 11355 list_del(&set->list); 11356 nft_use_dec(&table->use); 11357 if (set->flags & (NFT_SET_MAP | NFT_SET_OBJECT)) 11358 nft_map_deactivate(&ctx, set); (gdb)
[ 1360.549372] Last potentially related work creation: [ 1360.549376] kasan_save_stack+0x20/0x40 [ 1360.549384] __kasan_record_aux_stack+0x9b/0xb0 [ 1360.549392] __queue_work+0x3fb/0x780 [ 1360.549399] queue_work_on+0x4f/0x60 [ 1360.549407] nft_rhash_remove+0x33b/0x340 [nf_tables] [ 1360.549516] nf_tables_commit+0x1c6a/0x2620 [nf_tables] [ 1360.549625] nfnetlink_rcv_batch+0x728/0xdc0 [nfnetlink] [ 1360.549647] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink] [ 1360.549671] netlink_unicast+0x367/0x4f0 [ 1360.549680] netlink_sendmsg+0x34b/0x610 [ 1360.549690] ____sys_sendmsg+0x4d4/0x510 [ 1360.549697] ___sys_sendmsg+0xc9/0x120 [ 1360.549706] __sys_sendmsg+0xbe/0x140 [ 1360.549715] do_syscall_64+0x55/0x120 [ 1360.549725] entry_SYSCALL_64_after_hwframe+0x55/0x5d
Fixes: 0935d5588400 ("netfilter: nf_tables: asynchronous release") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org --- net/netfilter/nf_tables_api.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index ce7c573ce8cb..0fce320a7af3 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -8465,6 +8465,7 @@ static void __exit nf_tables_module_exit(void) unregister_netdevice_notifier(&nf_tables_flowtable_notifier); nft_chain_filter_fini(); nft_chain_route_fini(); + nf_tables_trans_destroy_flush_work(); unregister_pernet_subsys(&nf_tables_net_ops); cancel_work_sync(&trans_gc_work); cancel_work_sync(&trans_destroy_work);
commit a45e6889575c2067d3c0212b6bc1022891e65b91 upstream.
Unlike early commit path stage which triggers a call to abort, an explicit release of the batch is required on abort, otherwise mutex is released and commit_list remains in place.
Add WARN_ON_ONCE to ensure commit_list is empty from the abort path before releasing the mutex.
After this patch, commit_list is always assumed to be empty before grabbing the mutex, therefore
03c1f1ef1584 ("netfilter: Cleanup nft_net->module_list from nf_tables_exit_net()")
only needs to release the pending modules for registration.
Cc: stable@vger.kernel.org Fixes: c0391b6ab810 ("netfilter: nf_tables: missing validation from the abort path") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org --- net/netfilter/nf_tables_api.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 0fce320a7af3..b58e720830bc 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7545,10 +7545,11 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action) struct nftables_pernet *nft_net = net_generic(net, nf_tables_net_id); struct nft_trans *trans, *next; struct nft_trans_elem *te; + int err = 0;
if (action == NFNL_ABORT_VALIDATE && nf_tables_validate(net) < 0) - return -EAGAIN; + err = -EAGAIN;
list_for_each_entry_safe_reverse(trans, next, &nft_net->commit_list, list) { @@ -7681,7 +7682,7 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action) else nf_tables_module_autoload_cleanup(net);
- return 0; + return err; }
static int nf_tables_abort(struct net *net, struct sk_buff *skb, @@ -7695,6 +7696,8 @@ static int nf_tables_abort(struct net *net, struct sk_buff *skb, ret = __nf_tables_abort(net, action); nft_gc_seq_end(nft_net, gc_seq);
+ WARN_ON_ONCE(!list_empty(&nft_net->commit_list)); + mutex_unlock(&nft_net->commit_mutex);
return ret; @@ -8381,8 +8384,11 @@ static void __net_exit nf_tables_exit_net(struct net *net)
gc_seq = nft_gc_seq_begin(nft_net);
- if (!list_empty(&nft_net->commit_list)) - __nf_tables_abort(net, NFNL_ABORT_NONE); + WARN_ON_ONCE(!list_empty(&nft_net->commit_list)); + + if (!list_empty(&nft_net->module_list)) + nf_tables_module_autoload_cleanup(net); + __nft_release_tables(net);
nft_gc_seq_end(nft_net, gc_seq);
commit 0d459e2ffb541841714839e8228b845458ed3b27 upstream.
The commit mutex should not be released during the critical section between nft_gc_seq_begin() and nft_gc_seq_end(), otherwise, async GC worker could collect expired objects and get the released commit lock within the same GC sequence.
nf_tables_module_autoload() temporarily releases the mutex to load module dependencies, then it goes back to replay the transaction again. Move it at the end of the abort phase after nft_gc_seq_end() is called.
Cc: stable@vger.kernel.org Fixes: 720344340fb9 ("netfilter: nf_tables: GC transaction race with abort path") Reported-by: Kuan-Ting Chen hexrabbit@devco.re Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org --- net/netfilter/nf_tables_api.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index b58e720830bc..65bc949e0e6a 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7677,11 +7677,6 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action) nf_tables_abort_release(trans); }
- if (action == NFNL_ABORT_AUTOLOAD) - nf_tables_module_autoload(net); - else - nf_tables_module_autoload_cleanup(net); - return err; }
@@ -7698,6 +7693,14 @@ static int nf_tables_abort(struct net *net, struct sk_buff *skb,
WARN_ON_ONCE(!list_empty(&nft_net->commit_list));
+ /* module autoload needs to happen after GC sequence update because it + * temporarily releases and grabs mutex again. + */ + if (action == NFNL_ABORT_AUTOLOAD) + nf_tables_module_autoload(net); + else + nf_tables_module_autoload_cleanup(net); + mutex_unlock(&nft_net->commit_mutex);
return ret;
commit 1bc83a019bbe268be3526406245ec28c2458a518 upstream.
Hook unregistration is deferred to the commit phase, same occurs with hook updates triggered by the table dormant flag. When both commands are combined, this results in deleting a basechain while leaving its hook still registered in the core.
Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org --- net/netfilter/nf_tables_api.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 65bc949e0e6a..dc9d1b58b85d 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -903,6 +903,24 @@ static void nf_tables_table_disable(struct net *net, struct nft_table *table) #define __NFT_TABLE_F_UPDATE (__NFT_TABLE_F_WAS_DORMANT | \ __NFT_TABLE_F_WAS_AWAKEN)
+static bool nft_table_pending_update(const struct nft_ctx *ctx) +{ + struct nftables_pernet *nft_net = net_generic(ctx->net, nf_tables_net_id); + struct nft_trans *trans; + + if (ctx->table->flags & __NFT_TABLE_F_UPDATE) + return true; + + list_for_each_entry(trans, &nft_net->commit_list, list) { + if (trans->ctx.table == ctx->table && + trans->msg_type == NFT_MSG_DELCHAIN && + nft_is_base_chain(trans->ctx.chain)) + return true; + } + + return false; +} + static int nf_tables_updtable(struct nft_ctx *ctx) { struct nft_trans *trans; @@ -920,7 +938,7 @@ static int nf_tables_updtable(struct nft_ctx *ctx) return 0;
/* No dormant off/on/off/on games in single transaction */ - if (ctx->table->flags & __NFT_TABLE_F_UPDATE) + if (nft_table_pending_update(ctx)) return -EINVAL;
trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE,
linux-stable-mirror@lists.linaro.org
-
Pablo Neira Ayuso