From 147378c2ab28cecfd5b5aa6d8e13ede08b4d7473 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 9 Aug 2022 23:06:48 +0800 Subject: [PATCH] netfilter: nf_queue: do not allow packet truncation below transport header offset stable inclusion from stable-v5.10.135 commit 440dccd80f627e0e11ceb0429e4cdab61857d17e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5J9R4?from=project-issue CVE: CVE-2022-36946 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=440dccd80f627e0e11ceb0429e4cdab61857d17e -------------------------------- [ Upstream commit 99a63d36cb3ed5ca3aa6fcb64cffbeaf3b0fb164 ] Domingo Dirutigliano and Nicola Guerrera report kernel panic when sending nf_queue verdict with 1-byte nfta_payload attribute. The IP/IPv6 stack pulls the IP(v6) header from the packet after the input hook. If user truncates the packet below the header size, this skb_pull() will result in a malformed skb (skb->len < 0). Fixes: 7af4cc3fa158 ("[NETFILTER]: Add "nfnetlink_queue" netfilter queue handler over nfnetlink") Reported-by: Domingo Dirutigliano Signed-off-by: Florian Westphal Reviewed-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin Signed-off-by: Ziyang Xuan Reviewed-by: Yue Haibing Reviewed-by: Xiu Jianfeng Signed-off-by: Zheng Zengkai --- net/netfilter/nfnetlink_queue.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c index 1640da5c5077..72d30922ed29 100644 --- a/net/netfilter/nfnetlink_queue.c +++ b/net/netfilter/nfnetlink_queue.c @@ -838,11 +838,16 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) } static int -nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff) +nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff) { struct sk_buff *nskb; if (diff < 0) { + unsigned int min_len = skb_transport_offset(e->skb); + + if (data_len < min_len) + return -EINVAL; + if (pskb_trim(e->skb, data_len)) return -ENOMEM; } else if (diff > 0) { -- GitLab