CVE-2022-48643 Information

Description

In the Linux kernel the following vulnerability has been resolved:

netfilter: nf_tables: fix nft_counters_enabled underflow at nf_tables_addchain()

syzbot is reporting underflow of nft_counters_enabled counter at nf_tables_addchain() [1] for commit 43eb8949cfdffa76 ( etfilter: nf_tables: do not leave chain stats enabled on error) missed that nf_tables_chain_destroy() after nft_basechain_init() in the error path of nf_tables_addchain() decrements the counter because nft_basechain_init() makes nft_is_base_chain() return true by setting NFT_CHAIN_BASE flag.

Increment the counter immediately after returning from nft_basechain_init().

Reference

https://git.kernel.org/stable/c/710e3f526bd23a0d33435dedc52c3144de284378 https://git.kernel.org/stable/c/91aa52652f4b37089aff3cb53e83049d826fef6d https://git.kernel.org/stable/c/8bcad2a931313aeba076b76922d5813ef97d0a91 https://git.kernel.org/stable/c/921ebde3c0d22c8cba74ce8eb3cc4626abff1ccd