From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     heikki.krogerus@linux.intel.com, gregkh@linuxfoundation.org
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH] usb: typec: Check error number after calling ida_simple_get
Date:   Tue, 11 Jan 2022 15:17:51 +0800
Message-Id: <20220111071751.590487-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

If allocation fails, the ida_simple_get() will return error number.
So altmode_id_get() may return error number.
And then id will be used in altmode_id_remove, causing the BUG_ON().
Or it will be assigned to alt->id.
Therefore, it should be better to check it and return error if fails,
like the ida_simple_get() in typec_register_port().

Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/usb/typec/class.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index aeef453aa658..67b3670ede99 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -516,6 +516,9 @@ typec_register_altmode(struct device *parent,
 	struct altmode *alt;
 	int ret;
 
+	if (id < 0)
+		return ERR_PTR(id);
+
 	alt = kzalloc(sizeof(*alt), GFP_KERNEL);
 	if (!alt) {
 		altmode_id_remove(parent, id);
-- 
2.25.1