From: Wolfram Sang wsa+renesas@sang-engineering.com
[ Upstream commit 6af79f7fe748fe6a3c5c3a63d7f35981a82c2769 ]
Yang Yingliang reported a memleak: ===
I got memory leak as follows when doing fault injection test:
unreferenced object 0xffff888014aec078 (size 8): comm "xrun", pid 356, jiffies 4294910619 (age 16.332s) hex dump (first 8 bytes): 31 2d 30 30 31 63 00 00 1-001c.. backtrace: [<00000000eb56c0a9>] __kmalloc_track_caller+0x1a6/0x300 [<000000000b220ea3>] kvasprintf+0xad/0x140 [<00000000b83203e5>] kvasprintf_const+0x62/0x190 [<000000002a5eab37>] kobject_set_name_vargs+0x56/0x140 [<00000000300ac279>] dev_set_name+0xb0/0xe0 [<00000000b66ebd6f>] i2c_new_client_device+0x7e4/0x9a0
If device_register() returns error in i2c_new_client_device(), the name allocated by i2c_dev_set_name() need be freed. As comment of device_register() says, it should use put_device() to give up the reference in the error path.
=== I think this solution is less intrusive and more robust than he originally proposed solutions, though.
Reported-by: Yang Yingliang yangyingliang@huawei.com Closes: http://patchwork.ozlabs.org/project/linux-i2c/patch/20221124085448.3620240-1... Signed-off-by: Wolfram Sang wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang wsa@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/i2c-core-base.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 60746652fd525..7f30bcceebaed 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -931,8 +931,9 @@ int i2c_dev_irq_from_resources(const struct resource *resources, struct i2c_client * i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) { - struct i2c_client *client; - int status; + struct i2c_client *client; + bool need_put = false; + int status;
client = kzalloc(sizeof *client, GFP_KERNEL); if (!client) @@ -970,7 +971,6 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf client->dev.fwnode = info->fwnode;
device_enable_async_suspend(&client->dev); - i2c_dev_set_name(adap, client, info);
if (info->swnode) { status = device_add_software_node(&client->dev, info->swnode); @@ -982,6 +982,7 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf } }
+ i2c_dev_set_name(adap, client, info); status = device_register(&client->dev); if (status) goto out_remove_swnode; @@ -993,6 +994,7 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf
out_remove_swnode: device_remove_software_node(&client->dev); + need_put = true; out_err_put_of_node: of_node_put(info->of_node); out_err: @@ -1000,7 +1002,10 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf "Failed to register i2c client %s at 0x%02x (%d)\n", client->name, client->addr, status); out_err_silent: - kfree(client); + if (need_put) + put_device(&client->dev); + else + kfree(client); return ERR_PTR(status); } EXPORT_SYMBOL_GPL(i2c_new_client_device);