From bf4c441fd7d187d19f7a0a81645a74b1bf67c0b3 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 7 Aug 2023 19:09:54 +0800 Subject: [PATCH] netfilter: nft_set_pipapo: fix improper element removal stable inclusion from stable-v5.10.188 commit 3a91099ecd59a42d1632fcb152bf7222f268ea2b category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I7P3TK CVE: CVE-2023-4004 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3a91099ecd59a42d1632fcb152bf7222f268ea2b --------------------------- [ Upstream commit 87b5a5c209405cb6b57424cdfa226a6dbd349232 ] end key should be equal to start unless NFT_SET_EXT_KEY_END is present. Its possible to add elements that only have a start key ("{ 1.0.0.0 . 2.0.0.0 }") without an internval end. Insertion treats this via: if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END)) end = (const u8 *)nft_set_ext_key_end(ext)->data; else end = start; but removal side always uses nft_set_ext_key_end(). This is wrong and leads to garbage remaining in the set after removal next lookup/insert attempt will give: BUG: KASAN: slab-use-after-free in pipapo_get+0x8eb/0xb90 Read of size 1 at addr ffff888100d50586 by task nft-pipapo_uaf_/1399 Call Trace: kasan_report+0x105/0x140 pipapo_get+0x8eb/0xb90 nft_pipapo_insert+0x1dc/0x1710 nf_tables_newsetelem+0x31f5/0x4e00 .. Fixes: 3c4287f62044 ("nf_tables: Add set type for arbitrary concatenation of ranges") Reported-by: lonial con Reviewed-by: Stefano Brivio Signed-off-by: Florian Westphal Signed-off-by: Sasha Levin Signed-off-by: Lu Wei (cherry picked from commit 979e0dee90d90b455d76ebc0d8b67f23fed89686) --- net/netfilter/nft_set_pipapo.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c index 949da87dbb06..9dbb8677d2a0 100644 --- a/net/netfilter/nft_set_pipapo.c +++ b/net/netfilter/nft_set_pipapo.c @@ -1903,7 +1903,11 @@ static void nft_pipapo_remove(const struct net *net, const struct nft_set *set, int i, start, rules_fx; match_start = data; - match_end = (const u8 *)nft_set_ext_key_end(&e->ext)->data; + + if (nft_set_ext_exists(&e->ext, NFT_SET_EXT_KEY_END)) + match_end = (const u8 *)nft_set_ext_key_end(&e->ext)->data; + else + match_end = data; start = first_rule; rules_fx = rules_f0; -- Gitee