From 572f9a0d3f3feb8bd3422e88ad71882bc034b3ff Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 22 Mar 2022 17:41:47 -0700 Subject: [PATCH] llc: fix netdevice reference leaks in llc_ui_bind() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 764f4eb6846f5475f1244767d24d25dd86528a4a upstream. Whenever llc_ui_bind() and/or llc_ui_autobind() took a reference on a netdevice but subsequently fail, they must properly release their reference or risk the infamous message from unregister_netdevice() at device dismantle. unregister_netdevice: waiting for eth0 to become free. Usage count = 3 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: 赵子轩 Reported-by: Stoyan Manolov Link: https://lore.kernel.org/r/20220323004147.1990845-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/llc/af_llc.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c index 0b3adf7594ffe..3bf5dee00c708 100644 --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -311,6 +311,10 @@ static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr) sock_reset_flag(sk, SOCK_ZAPPED); rc = 0; out: + if (rc) { + dev_put(llc->dev); + llc->dev = NULL; + } return rc; } @@ -409,6 +413,10 @@ static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen) out_put: llc_sap_put(sap); out: + if (rc) { + dev_put(llc->dev); + llc->dev = NULL; + } release_sock(sk); return rc; }