netfilter: nf_tables: incorrect error path handling with NFT_MSG_NEWRULE
In case of error when adding a new rule that refers to an anonymous set, deactivate expressions via NFT_TRANS_PREPARE state, not NFT_TRANS_RELEASE. Thus, the lookup expression marks anonymous sets as inactive in the next generation to ensure it is not reachable in this transaction anymore and decrement the set refcount as introduced by c1592a89 ("netfilter: nf_tables: deactivate anonymous set from preparation phase"). The abort step takes care of undoing the anonymous set. This is also consistent with rule deletion, where NFT_TRANS_PREPARE is used. Note that this error path is exercised in the preparation step of the commit protocol. This patch replaces nf_tables_rule_release() by the deactivate and destroy calls, this time with NFT_TRANS_PREPARE. Due to this incorrect error handling, it is possible to access a dangling pointer to the anonymous set that remains in the transaction list. [1009.379054] BUG: KASAN: use-after-free in nft_set_lookup_global+0x147/0x1a0 [nf_tables] [1009.379106] Read of size 8 at addr ffff88816c4c8020 by task nft-rule-add/137110 [1009.379116] CPU: 7 PID: 137110 Comm: nft-rule-add Not tainted 6.4.0-rc4+ #256 [1009.379128] Call Trace: [1009.379132] <TASK> [1009.379135] dump_stack_lvl+0x33/0x50 [1009.379146] ? nft_set_lookup_global+0x147/0x1a0 [nf_tables] [1009.379191] print_address_description.constprop.0+0x27/0x300 [1009.379201] kasan_report+0x107/0x120 [1009.379210] ? nft_set_lookup_global+0x147/0x1a0 [nf_tables] [1009.379255] nft_set_lookup_global+0x147/0x1a0 [nf_tables] [1009.379302] nft_lookup_init+0xa5/0x270 [nf_tables] [1009.379350] nf_tables_newrule+0x698/0xe50 [nf_tables] [1009.379397] ? nf_tables_rule_release+0xe0/0xe0 [nf_tables] [1009.379441] ? kasan_unpoison+0x23/0x50 [1009.379450] nfnetlink_rcv_batch+0x97c/0xd90 [nfnetlink] [1009.379470] ? nfnetlink_rcv_msg+0x480/0x480 [nfnetlink] [1009.379485] ? __alloc_skb+0xb8/0x1e0 [1009.379493] ? __alloc_skb+0xb8/0x1e0 [1009.379502] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0 [1009.379509] ? unwind_get_return_address+0x2a/0x40 [1009.379517] ? write_profile+0xc0/0xc0 [1009.379524] ? avc_lookup+0x8f/0xc0 [1009.379532] ? __rcu_read_unlock+0x43/0x60 Fixes: 958bee14 ("netfilter: nf_tables: use new transaction infrastructure to handle sets") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
parent
a1a64a15
-
mentioned in commit 44ebe988
-
mentioned in commit 4aaa3b73
-
mentioned in commit bdace3b1
-
mentioned in commit 26b5a571
-
mentioned in commit 4bedf9ee
-
mentioned in commit 2ba7e7eb
-
mentioned in commit 4004f12a
-
mentioned in commit 314a8697
-
mentioned in commit df27be7c
-
mentioned in commit 891cd2ed
-
mentioned in commit 0b342806
-
mentioned in commit a1547f81
Please register or sign in to comment