From c9f314f6e315a5518432761fea864196a290f799 Mon Sep 17 00:00:00 2001

From: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

Date: Thu, 17 Jun 2021 18:01:32 +0900

Subject: [PATCH] Fix "DHCP broken in libslirp v4.6.0"

Fix issue 48

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

---

 src/bootp.c | 4 +++-

 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/bootp.c b/src/bootp.c

index cafa1eb..0a35873 100644

--- a/src/bootp.c

+++ b/src/bootp.c

@@ -359,7 +359,9 @@ static void bootp_reply(Slirp *slirp,

     daddr.sin_addr.s_addr = 0xffffffffu;

-    m->m_len = sizeof(struct bootp_t) - sizeof(struct ip) - sizeof(struct udphdr);

+    assert ((q - rbp->bp_vend + 1) <= DHCP_OPT_LEN);

+

+    m->m_len = sizeof(struct bootp_t) + (q - rbp->bp_vend + 1) - sizeof(struct ip) - sizeof(struct udphdr);

     udp_output(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY);

 }

-- 

2.29.0