From 0f7d9b31ce7abdbb29bf018131ac920c9f698518 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 13 Dec 2021 05:45:44 -0800 Subject: netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy() We need to use list_for_each_entry_safe() iterator because we can not access @catchall after kfree_rcu() call. syzbot reported: BUG: KASAN: use-after-free in nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline] BUG: KASAN: use-after-free in nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline] BUG: KASAN: use-after-free in nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493 Read of size 8 at addr ffff8880716e5b80 by task syz-executor.3/8871 CPU: 1 PID: 8871 Comm: syz-executor.3 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline] nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline] nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493 __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626 nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 blocking_notifier_call_chain kernel/notifier.c:318 [inline] blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306 netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f75fbf28adb Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffd8da7ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb RDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 0000000000000003 RBP: 00007f75fc08a960 R08: 0000000000000000 R09: 00007f75fc08e830 R10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3 R13: 00007ffd8da7ed10 R14: 00007f75fc088f60 R15: 0000000000000032 Allocated by task 8886: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:269 [inline] kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575 kmalloc include/linux/slab.h:590 [inline] nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [inline] nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [inline] nft_add_set_elem+0x232e/0x2f40 net/netfilter/nf_tables_api.c:5936 nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032 nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline] nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 15335: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xd1/0x110 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] __cache_free mm/slab.c:3445 [inline] kmem_cache_free_bulk+0x67/0x1e0 mm/slab.c:3766 kfree_bulk include/linux/slab.h:446 [inline] kfree_rcu_work+0x51c/0xa10 kernel/rcu/tree.c:3273 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Last potentially related work creation: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 __kasan_record_aux_stack+0xb5/0xe0 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3550 nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4489 [inline] nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline] nft_set_destroy+0x34a/0x4f0 net/netfilter/nf_tables_api.c:4493 __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626 nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 blocking_notifier_call_chain kernel/notifier.c:318 [inline] blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306 netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8880716e5b80 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 0 bytes inside of 64-byte region [ffff8880716e5b80, ffff8880716e5bc0) The buggy address belongs to the page: page:ffffea0001c5b940 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880716e5c00 pfn:0x716e5 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0000911848 ffffea00007c4d48 ffff888010c40200 raw: ffff8880716e5c00 ffff8880716e5000 000000010000001e 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x242040(__GFP_IO|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 3638, ts 211086074437, free_ts 211031029429 prep_new_page mm/page_alloc.c:2418 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369 __alloc_pages_node include/linux/gfp.h:570 [inline] kmem_getpages mm/slab.c:1377 [inline] cache_grow_begin+0x75/0x470 mm/slab.c:2593 cache_alloc_refill+0x27f/0x380 mm/slab.c:2965 ____cache_alloc mm/slab.c:3048 [inline] ____cache_alloc mm/slab.c:3031 [inline] __do_cache_alloc mm/slab.c:3275 [inline] slab_alloc mm/slab.c:3316 [inline] __do_kmalloc mm/slab.c:3700 [inline] __kmalloc+0x3b3/0x4d0 mm/slab.c:3711 kmalloc include/linux/slab.h:595 [inline] kzalloc include/linux/slab.h:724 [inline] tomoyo_get_name+0x234/0x480 security/tomoyo/memory.c:173 tomoyo_parse_name_union+0xbc/0x160 security/tomoyo/util.c:260 tomoyo_update_path_number_acl security/tomoyo/file.c:687 [inline] tomoyo_write_file+0x629/0x7f0 security/tomoyo/file.c:1034 tomoyo_write_domain2+0x116/0x1d0 security/tomoyo/common.c:1152 tomoyo_add_entry security/tomoyo/common.c:2042 [inline] tomoyo_supervisor+0xbc7/0xf00 security/tomoyo/common.c:2103 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline] tomoyo_path_number_perm+0x419/0x590 security/tomoyo/file.c:734 security_file_ioctl+0x50/0xb0 security/security.c:1541 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0xb3/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3309 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3388 slab_destroy mm/slab.c:1627 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1647 cache_flusharray mm/slab.c:3418 [inline] ___cache_free+0x4cc/0x610 mm/slab.c:3480 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x4e/0x110 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x97/0xb0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slab.c:3261 [inline] kmem_cache_alloc_node+0x2ea/0x590 mm/slab.c:3599 __alloc_skb+0x215/0x340 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1126 [inline] nlmsg_new include/net/netlink.h:953 [inline] rtmsg_ifinfo_build_skb+0x72/0x1a0 net/core/rtnetlink.c:3808 rtmsg_ifinfo_event net/core/rtnetlink.c:3844 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3835 [inline] rtmsg_ifinfo+0x83/0x120 net/core/rtnetlink.c:3853 netdev_state_change net/core/dev.c:1395 [inline] netdev_state_change+0x114/0x130 net/core/dev.c:1386 linkwatch_do_dev+0x10e/0x150 net/core/link_watch.c:167 __linkwatch_run_queue+0x233/0x6a0 net/core/link_watch.c:213 linkwatch_event+0x4a/0x60 net/core/link_watch.c:252 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 Memory state around the buggy address: ffff8880716e5a80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880716e5b00: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff8880716e5b80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8880716e5c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880716e5c80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc Fixes: aaa31047a6d2 ("netfilter: nftables: add catch-all set element support") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/netfilter') diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index c0851fec11d4..c20772822637 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -4481,9 +4481,9 @@ struct nft_set_elem_catchall { static void nft_set_catchall_destroy(const struct nft_ctx *ctx, struct nft_set *set) { - struct nft_set_elem_catchall *catchall; + struct nft_set_elem_catchall *next, *catchall; - list_for_each_entry_rcu(catchall, &set->catchall_list, list) { + list_for_each_entry_safe(catchall, next, &set->catchall_list, list) { list_del_rcu(&catchall->list); nft_set_elem_destroy(set, catchall->elem, true); kfree_rcu(catchall); -- cgit v1.2.3-59-g8ed1b From ebb966d3bdfed581ecccbb4a7432341baf7619b4 Mon Sep 17 00:00:00 2001 From: Ignacy Gawędzki Date: Fri, 10 Dec 2021 16:31:27 +0100 Subject: netfilter: fix regression in looped (broad|multi)cast's MAC handling MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In commit 5648b5e1169f ("netfilter: nfnetlink_queue: fix OOB when mac header was cleared"), the test for non-empty MAC header introduced in commit 2c38de4c1f8da7 ("netfilter: fix looped (broad|multi)cast's MAC handling") has been replaced with a test for a set MAC header. This breaks the case when the MAC header has been reset (using skb_reset_mac_header), as is the case with looped-back multicast packets. As a result, the packets ending up in NFQUEUE get a bogus hwaddr interpreted from the first bytes of the IP header. This patch adds a test for a non-empty MAC header in addition to the test for a set MAC header. The same two tests are also implemented in nfnetlink_log.c, where the initial code of commit 2c38de4c1f8da7 ("netfilter: fix looped (broad|multi)cast's MAC handling") has not been touched, but where supposedly the same situation may happen. Fixes: 5648b5e1169f ("netfilter: nfnetlink_queue: fix OOB when mac header was cleared") Signed-off-by: Ignacy Gawędzki Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nfnetlink_log.c | 3 ++- net/netfilter/nfnetlink_queue.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) (limited to 'net/netfilter') diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 691ef4cffdd9..7f83f9697fc1 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -556,7 +556,8 @@ __build_packet_message(struct nfnl_log_net *log, goto nla_put_failure; if (indev && skb->dev && - skb->mac_header != skb->network_header) { + skb_mac_header_was_set(skb) && + skb_mac_header_len(skb) != 0) { struct nfulnl_msg_packet_hw phw; int len; diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c index 5837e8efc9c2..f0b9e21a2452 100644 --- a/net/netfilter/nfnetlink_queue.c +++ b/net/netfilter/nfnetlink_queue.c @@ -560,7 +560,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, goto nla_put_failure; if (indev && entskb->dev && - skb_mac_header_was_set(entskb)) { + skb_mac_header_was_set(entskb) && + skb_mac_header_len(entskb) != 0) { struct nfqnl_msg_packet_hw phw; int len; -- cgit v1.2.3-59-g8ed1b From 76f12e632a15a20c8de3532d64a0708cf0e32f11 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 9 Dec 2021 17:39:26 +0100 Subject: netfilter: ctnetlink: remove expired entries first When dumping conntrack table to userspace via ctnetlink, check if the ct has already expired before doing any of the 'skip' checks. This expires dead entries faster. /proc handler also removes outdated entries first. Reported-by: Vitaly Zuevsky Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'net/netfilter') diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 81d03acf68d4..ec4164c32d27 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1195,8 +1195,6 @@ restart: } hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[cb->args[0]], hnnode) { - if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL) - continue; ct = nf_ct_tuplehash_to_ctrack(h); if (nf_ct_is_expired(ct)) { if (i < ARRAY_SIZE(nf_ct_evict) && @@ -1208,6 +1206,9 @@ restart: if (!net_eq(net, nf_ct_net(ct))) continue; + if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL) + continue; + if (cb->args[1]) { if (ct != last) continue; -- cgit v1.2.3-59-g8ed1b