From b08019f0b2fbc30c75169a160acb9fd9af5d68f4 Mon Sep 17 00:00:00 2001
From: Juergen Gross <jgross@suse.com>
Date: Tue, 21 Nov 2023 10:49:53 +0100
Subject: [PATCH] Mini-OS: fix 9pfs response receiving

When copying a 9pfs response chunk from the ring buffer across the
ring end, the local ring pointer and length field are not updated
correctly. Fix that.

Fixes: 0924fec1de58 ("Mini-OS: add 9pfs transport layer")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
---
 9pfront.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/9pfront.c b/9pfront.c
index 43c7409..35c5552 100644
--- a/9pfront.c
+++ b/9pfront.c
@@ -386,7 +386,9 @@ static void copy_bufs(unsigned char **buf1, unsigned char **buf2,
             printk("9pfs: short copy (dropping %u bytes)\n", len - *len1);
             len = *len1;
         }
-        memcpy(target, *buf1, *len1);
+        memcpy(target, *buf1, len);
+        *buf1 += len;
+        *len1 -= len;
     }
 }
 
-- 
2.39.5