From: Yajun Deng Date: Mon, 30 Aug 2021 09:16:40 +0000 (+0800) Subject: net: ipv4: Fix the warning for dereference X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1b9fbe813016b08e08b22ddba4ddbf9cb1b04b00;p=linux.git net: ipv4: Fix the warning for dereference Add a if statements to avoid the warning. Dan Carpenter report: The patch faf482ca196a: "net: ipv4: Move ip_options_fragment() out of loop" from Aug 23, 2021, leads to the following Smatch complaint: net/ipv4/ip_output.c:833 ip_do_fragment() warn: variable dereferenced before check 'iter.frag' (see line 828) Reported-by: Dan Carpenter Fixes: faf482ca196a ("net: ipv4: Move ip_options_fragment() out of loop") Link: https://lore.kernel.org/netdev/20210830073802.GR7722@kadam/T/#t Signed-off-by: Yajun Deng Signed-off-by: David S. Miller --- diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 9a8f05d5476ec..9bca57ef8b838 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -825,7 +825,9 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, /* Everything is OK. Generate! */ ip_fraglist_init(skb, iph, hlen, &iter); - ip_options_fragment(iter.frag); + + if (iter.frag) + ip_options_fragment(iter.frag); for (;;) { /* Prepare header of the next frame,