From: Michael Zaidman michael.zaidman@gmail.com
[ Upstream commit a94f61e63f337d95001e1a976ab701100fa1d666 ]
The below scenario causes the kernel NULL pointer dereference failure: 1. sudo insmod hid-ft260.ko 2. sudo modprobe lm75 3. unplug USB hid-ft260 4. plug USB hid-ft260
[ +0.000006] Call Trace: [ +0.000004] __i2c_smbus_xfer.part.0+0xd1/0x310 [ +0.000007] ? ft260_smbus_write+0x140/0x140 [hid_ft260] [ +0.000005] __i2c_smbus_xfer+0x2b/0x80 [ +0.000004] i2c_smbus_xfer+0x61/0xf0 [ +0.000005] i2c_default_probe+0xf9/0x130 [ +0.000004] i2c_detect_address+0x84/0x160 [ +0.000004] ? kmem_cache_alloc_trace+0xf6/0x200 [ +0.000009] ? i2c_detect.isra.0+0x69/0x130 [ +0.000005] i2c_detect.isra.0+0xbf/0x130 [ +0.000004] ? __process_new_driver+0x30/0x30 [ +0.000004] __process_new_adapter+0x18/0x20 [ +0.000004] bus_for_each_drv+0x84/0xd0 [ +0.000003] i2c_register_adapter+0x1e4/0x400 [ +0.000005] i2c_add_adapter+0x5c/0x80 [ +0.000004] ft260_probe.cold+0x222/0x2e2 [hid_ft260] [ +0.000006] hid_device_probe+0x10e/0x170 [hid] [ +0.000009] really_probe+0xff/0x460 [ +0.000004] driver_probe_device+0xe9/0x160 [ +0.000003] __device_attach_driver+0x71/0xd0 [ +0.000004] ? driver_allows_async_probing+0x50/0x50 [ +0.000004] bus_for_each_drv+0x84/0xd0 [ +0.000002] __device_attach+0xde/0x1e0 [ +0.000004] device_initial_probe+0x13/0x20 [ +0.000004] bus_probe_device+0x8f/0xa0 [ +0.000003] device_add+0x333/0x5f0
It happened when i2c core probed for the devices associated with the lm75 driver by invoking 2c_detect()-->..-->ft260_smbus_write() from within the ft260_probe before setting the adapter data with i2c_set_adapdata().
Moving the i2c_set_adapdata() before i2c_add_adapter() fixed the failure.
Signed-off-by: Michael Zaidman michael.zaidman@gmail.com Signed-off-by: Germain Hebert germain.hebert@ca.abb.com Signed-off-by: Jiri Kosina jkosina@suse.cz Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hid/hid-ft260.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c index 4ef1c3b8094ea..8ee77f4afe9ff 100644 --- a/drivers/hid/hid-ft260.c +++ b/drivers/hid/hid-ft260.c @@ -966,24 +966,23 @@ static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id) mutex_init(&dev->lock); init_completion(&dev->wait);
+ ret = ft260_xfer_status(dev); + if (ret) + ft260_i2c_reset(hdev); + + i2c_set_adapdata(&dev->adap, dev); ret = i2c_add_adapter(&dev->adap); if (ret) { hid_err(hdev, "failed to add i2c adapter\n"); goto err_hid_close; }
- i2c_set_adapdata(&dev->adap, dev); - ret = sysfs_create_group(&hdev->dev.kobj, &ft260_attr_group); if (ret < 0) { hid_err(hdev, "failed to create sysfs attrs\n"); goto err_i2c_free; }
- ret = ft260_xfer_status(dev); - if (ret) - ft260_i2c_reset(hdev); - return 0;
err_i2c_free: