Message ID | 20190812200707.25587-1-dsahern@kernel.org |
---|---|
State | Accepted |
Delegated to: | David Miller |
Headers | show |
Series | [net] netlink: Fix nlmsg_parse as a wrapper for strict message parsing | expand |
On 8/12/19 10:07 PM, David Ahern wrote: > From: David Ahern <dsahern@gmail.com> > > Eric reported a syzbot warning: > > > The root cause is nlmsg_parse calling __nla_parse which means the > header struct size is not checked. > > nlmsg_parse should be a wrapper around __nlmsg_parse with > NL_VALIDATE_STRICT for the validate argument very much like > nlmsg_parse_deprecated is for NL_VALIDATE_LIBERAL. > > Fixes: 3de6440354465 ("netlink: re-add parse/validate functions in strict mode") > Reported-by: Eric Dumazet <edumazet@google.com> > Reported-by: syzbot <syzkaller@googlegroups.com> > Signed-off-by: David Ahern <dsahern@gmail.com> > --- Reviewed-by: Eric Dumazet <edumazet@google.com> Thanks !
On Mon, 12 Aug 2019 13:07:07 -0700, David Ahern wrote: > From: David Ahern <dsahern@gmail.com> > > Eric reported a syzbot warning: > > BUG: KMSAN: uninit-value in nh_valid_get_del_req+0x6f1/0x8c0 net/ipv4/nexthop.c:1510 > CPU: 0 PID: 11812 Comm: syz-executor444 Not tainted 5.3.0-rc3+ #17 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x191/0x1f0 lib/dump_stack.c:113 > kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109 > __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294 > nh_valid_get_del_req+0x6f1/0x8c0 net/ipv4/nexthop.c:1510 > rtm_del_nexthop+0x1b1/0x610 net/ipv4/nexthop.c:1543 > rtnetlink_rcv_msg+0x115a/0x1580 net/core/rtnetlink.c:5223 > netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477 > rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5241 > netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] > netlink_unicast+0xf6c/0x1050 net/netlink/af_netlink.c:1328 > netlink_sendmsg+0x110f/0x1330 net/netlink/af_netlink.c:1917 > sock_sendmsg_nosec net/socket.c:637 [inline] > sock_sendmsg net/socket.c:657 [inline] > ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311 > __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413 > __do_sys_sendmmsg net/socket.c:2442 [inline] > __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439 > __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439 > do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 > entry_SYSCALL_64_after_hwframe+0x63/0xe7 > > The root cause is nlmsg_parse calling __nla_parse which means the > header struct size is not checked. > > nlmsg_parse should be a wrapper around __nlmsg_parse with > NL_VALIDATE_STRICT for the validate argument very much like > nlmsg_parse_deprecated is for NL_VALIDATE_LIBERAL. > > Fixes: 3de6440354465 ("netlink: re-add parse/validate functions in strict mode") > Reported-by: Eric Dumazet <edumazet@google.com> > Reported-by: syzbot <syzkaller@googlegroups.com> > Signed-off-by: David Ahern <dsahern@gmail.com> Applied, thank you!
diff --git a/include/net/netlink.h b/include/net/netlink.h index e4650e5b64a1..b140c8f1be22 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -684,9 +684,8 @@ static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, const struct nla_policy *policy, struct netlink_ext_ack *extack) { - return __nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), - nlmsg_attrlen(nlh, hdrlen), policy, - NL_VALIDATE_STRICT, extack); + return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, + NL_VALIDATE_STRICT, extack); } /**