From: Florian Schmidt <florian.schmidt@neclab.eu>
Date: Mon, 20 May 2019 11:29:50 +0000 (+0200)
Subject: sockets.c: Refuse to deal with non-sockets
X-Git-Tag: RELEASE-0.4~66
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=44d3880c58fa24e0390062617e70a1ad45922603;p=unikraft%2Flibs%2Flwip.git

sockets.c: Refuse to deal with non-sockets

Otherwise, socket_net_file_get() will try to look up lwip's file
descriptors for file objects not created by lwip, reading garbage from
where it expects sock_fd in sock_net_file.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>
---

diff --git a/sockets.c b/sockets.c
index bbee72b..b2a65bb 100644
--- a/sockets.c
+++ b/sockets.c
@@ -65,6 +65,12 @@ static inline struct sock_net_file *sock_net_file_get(int fd)
 		file = ERR2PTR(-EINVAL);
 		goto EXIT;
 	}
+	if (fos->f_dentry->d_vnode->v_type != VSOCK) {
+		LWIP_DEBUGF(SOCKETS_DEBUG,
+			    ("file descriptor is not a socket\n"));
+		file = ERR2PTR(-EBADF);
+		goto EXIT;
+	}
 	file = __containerof(fos, struct sock_net_file, vfscore_file);
 EXIT:
 	return file;
@@ -122,6 +128,7 @@ static int sock_fd_alloc(struct vnops *v_op, int sock_fd)
 	uk_mutex_init(&s_vnode->v_lock);
 	s_vnode->v_refcnt = 1;
 	s_vnode->v_data = file;
+	s_vnode->v_type = VSOCK;
 
 	file->sock_fd = sock_fd;
 	LWIP_DEBUGF(SOCKETS_DEBUG, ("Allocated socket %d (%x)\n",