From: Xin Long Date: Sat, 28 Jan 2023 15:58:35 +0000 (-0500) Subject: cipso_ipv4: use iph_set_totlen in skbuff_setattr X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7eb072be41ba4d8ecea17092dece50c7375d8980;p=linux.git cipso_ipv4: use iph_set_totlen in skbuff_setattr It may process IPv4 TCP GSO packets in cipso_v4_skbuff_setattr(), so the iph->tot_len update should use iph_set_totlen(). Note that for these non GSO packets, the new iph tot_len with extra iph option len added may become greater than 65535, the old process will cast it and set iph->tot_len to it, which is a bug. In theory, iph options shouldn't be added for these big packets in here, a fix may be needed here in the future. For now this patch is only to set iph->tot_len to 0 when it happens. Signed-off-by: Xin Long Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski --- diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index 6cd3b6c559f05..79ae7204e8edb 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -2222,7 +2222,7 @@ int cipso_v4_skbuff_setattr(struct sk_buff *skb, memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); if (len_delta != 0) { iph->ihl = 5 + (opt_len >> 2); - iph->tot_len = htons(skb->len); + iph_set_totlen(iph, skb->len); } ip_send_check(iph);