From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3265D1C26 for ; Wed, 23 Nov 2022 09:10:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DA61C433C1; Wed, 23 Nov 2022 09:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669194636; bh=+jxuUetz6/AHFTUaB/M1wDvPnR8Pv/0B1K+209du3cc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X9m8Mbm3VMKxSkxkphkL+cSPFXhAGdl91EHsR5wKzhFwn7Ck2UmMPBvGnpuguPr67 fLQ7tA/RmGNZF5QxzDBFi9Elu/VUFXMwSiEYW3lZPg8twT0blLelM8S8LCXwKmh78r zzOwlokCbPuY7zDxuCl3LaGdJTv0Wc5ksyt0iwm0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhengchao Shao , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 019/156] hamradio: fix issue of dev reference count leakage in bpq_device_event() Date: Wed, 23 Nov 2022 09:49:36 +0100 Message-Id: <20221123084558.605998818@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084557.816085212@linuxfoundation.org> References: <20221123084557.816085212@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Zhengchao Shao [ Upstream commit 85cbaf032d3cd9f595152625eda5d4ecb1d6d78d ] When following tests are performed, it will cause dev reference counting leakage. a)ip link add bond2 type bond mode balance-rr b)ip link set bond2 up c)ifenslave -f bond2 rose1 d)ip link del bond2 When new bond device is created, the default type of the bond device is ether. And the bond device is up, bpq_device_event() receives the message and creates a new bpq device. In this case, the reference count value of dev is hold once. But after "ifenslave -f bond2 rose1" command is executed, the type of the bond device is changed to rose. When the bond device is unregistered, bpq_device_event() will not put the dev reference count. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Zhengchao Shao Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/hamradio/bpqether.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/hamradio/bpqether.c b/drivers/net/hamradio/bpqether.c index e2ad3c2e8df5..e0b9823170bf 100644 --- a/drivers/net/hamradio/bpqether.c +++ b/drivers/net/hamradio/bpqether.c @@ -511,7 +511,7 @@ static int bpq_device_event(struct notifier_block *this, if (!net_eq(dev_net(dev), &init_net)) return NOTIFY_DONE; - if (!dev_is_ethdev(dev)) + if (!dev_is_ethdev(dev) && !bpq_get_ax25_dev(dev)) return NOTIFY_DONE; switch (event) { -- 2.35.1