From 109f5845a60fc0ef90ce2e842b4cb7ad2752c063 Mon Sep 17 00:00:00 2001 From: Peilin Ye Date: Tue, 11 Aug 2020 03:46:40 -0400 Subject: [PATCH] ipvs: Fix uninit-value in do_ip_vs_set_ctl() [ Upstream commit c5a8a8498eed1c164afc94f50a939c1a10abf8ad ] do_ip_vs_set_ctl() is referencing uninitialized stack value when `len` is zero. Fix it. Reported-by: syzbot+23b5f9e7caf61d9a3898@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?id=46ebfb92a8a812621a001ef04d90dfa459520fe2 Suggested-by: Julian Anastasov Signed-off-by: Peilin Ye Acked-by: Julian Anastasov Reviewed-by: Simon Horman Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/ipvs/ip_vs_ctl.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index 3cccc88ef817..99168af0c28d 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -2465,6 +2465,10 @@ do_ip_vs_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) /* Set timeout values for (tcp tcpfin udp) */ ret = ip_vs_set_timeout(ipvs, (struct ip_vs_timeout_user *)arg); goto out_unlock; + } else if (!len) { + /* No more commands with len == 0 below */ + ret = -EINVAL; + goto out_unlock; } usvc_compat = (struct ip_vs_service_user *)arg; @@ -2541,9 +2545,6 @@ do_ip_vs_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) break; case IP_VS_SO_SET_DELDEST: ret = ip_vs_del_dest(svc, &udest); - break; - default: - ret = -EINVAL; } out_unlock: