Module Name: src
Committed By: riastradh
Date: Wed Jun 29 23:15:08 UTC 2022
Modified Files:
src/sys/net: rtsock_shared.c
Log Message:
route(4): Avoid unaligned access to struct rt_msghdr, take two.
Can't even take the address of the misaligned struct member for
memcpy. Just copy the header out into a stack variable instead.
Reported-by: syzbot+083d9be5cb3c2e78e...@syzkaller.appspotmail.com
To generate a diff of this commit:
cvs rdiff -u -r1.20 -r1.21 src/sys/net/rtsock_shared.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/net/rtsock_shared.c
diff -u src/sys/net/rtsock_shared.c:1.20 src/sys/net/rtsock_shared.c:1.21
--- src/sys/net/rtsock_shared.c:1.20 Sun Jun 26 21:42:19 2022
+++ src/sys/net/rtsock_shared.c Wed Jun 29 23:15:08 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: rtsock_shared.c,v 1.20 2022/06/26 21:42:19 riastradh Exp $ */
+/* $NetBSD: rtsock_shared.c,v 1.21 2022/06/29 23:15:08 riastradh Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -61,7 +61,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rtsock_shared.c,v 1.20 2022/06/26 21:42:19 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rtsock_shared.c,v 1.21 2022/06/29 23:15:08 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_inet.h"
@@ -647,6 +647,7 @@ int
COMPATNAME(route_output)(struct mbuf *m, struct socket *so)
{
struct sockproto proto = { .sp_family = PF_XROUTE, };
+ struct rt_xmsghdr hdr;
struct rt_xmsghdr *rtm = NULL;
struct rt_xmsghdr *old_rtm = NULL, *new_rtm = NULL;
struct rtentry *rt = NULL;
@@ -658,7 +659,6 @@ COMPATNAME(route_output)(struct mbuf *m,
int bound = curlwp_bind();
bool do_rt_free = false;
struct sockaddr_storage netmask;
- unsigned short msglen;
#define senderr(e) do { error = e; goto flush;} while (/*CONSTCOND*/ 0)
if (m == NULL || ((m->m_len < sizeof(int32_t)) &&
@@ -673,9 +673,8 @@ COMPATNAME(route_output)(struct mbuf *m,
info.rti_info[RTAX_DST] = NULL;
senderr(EINVAL);
}
- memcpy(&msglen, &mtod(m, struct rt_xmsghdr *)->rtm_msglen,
- sizeof(msglen));
- if (len != msglen) {
+ m_copydata(m, 0, sizeof(hdr), &hdr);
+ if (len != hdr.rtm_msglen) {
info.rti_info[RTAX_DST] = NULL;
senderr(EINVAL);
}
