From: Yang Yingliang yangyingliang@huawei.com
[ Upstream commit df0a18149474c7e6b21f6367fbc6bc8d0f192444 ]
I got memory leak as follows:
unreferenced object 0xffff88801f0b2200 (size 64): comm "i2c-lis2hh12-21", pid 5455, jiffies 4294944606 (age 15.224s) hex dump (first 32 bytes): 72 65 67 75 6c 61 74 6f 72 3a 72 65 67 75 6c 61 regulator:regula 74 6f 72 2e 30 2d 2d 69 32 63 3a 31 2d 30 30 31 tor.0--i2c:1-001 backtrace: [<00000000bf5b0c3b>] __kmalloc_track_caller+0x19f/0x3a0 [<0000000050da42d9>] kvasprintf+0xb5/0x150 [<000000004bbbed13>] kvasprintf_const+0x60/0x190 [<00000000cdac7480>] kobject_set_name_vargs+0x56/0x150 [<00000000bf83f8e8>] dev_set_name+0xc0/0x100 [<00000000cc1cf7e3>] device_link_add+0x6b4/0x17c0 [<000000009db9faed>] _regulator_get+0x297/0x680 [<00000000845e7f2b>] _devm_regulator_get+0x5b/0xe0 [<000000003958ee25>] st_sensors_power_enable+0x71/0x1b0 [st_sensors] [<000000005f450f52>] st_accel_i2c_probe+0xd9/0x150 [st_accel_i2c] [<00000000b5f2ab33>] i2c_device_probe+0x4d8/0xbe0 [<0000000070fb977b>] really_probe+0x299/0xc30 [<0000000088e226ce>] __driver_probe_device+0x357/0x500 [<00000000c21dda32>] driver_probe_device+0x4e/0x140 [<000000004e650441>] __device_attach_driver+0x257/0x340 [<00000000cf1891b8>] bus_for_each_drv+0x166/0x1e0
When device_register() returns an error, the name allocated in dev_set_name() will be leaked, the put_device() should be used instead of kfree() to give up the device reference, then the name will be freed in kobject_cleanup() and the references of consumer and supplier will be decreased in device_link_release_fn().
Fixes: 287905e68dd2 ("driver core: Expose device link details in sysfs") Reported-by: Hulk Robot hulkci@huawei.com Reviewed-by: Saravana Kannan saravanak@google.com Reviewed-by: Rafael J. Wysocki rafael@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com Link: https://lore.kernel.org/r/20210930085714.2057460-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/base/core.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c index f150ebebb3068..7033d0c33a026 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -809,9 +809,7 @@ struct device_link *device_link_add(struct device *consumer, dev_bus_name(supplier), dev_name(supplier), dev_bus_name(consumer), dev_name(consumer)); if (device_register(&link->link_dev)) { - put_device(consumer); - put_device(supplier); - kfree(link); + put_device(&link->link_dev); link = NULL; goto out; }