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| author | Hans de Goede <hdegoede@redhat.com> | 2019-04-20 13:21:50 +0200 |
|---|---|---|
| committer | Benjamin Tissoires <benjamin.tissoires@redhat.com> | 2019-04-23 18:00:41 +0200 |
| commit | f41d766c34cbab024412d433a43d2d83a37e5135 (patch) | |
| tree | 2c86aad750cb8a407a61ef1f8b39329475a22cd5 /drivers/hid/hid-logitech-dj.c | |
| parent | 61d14de2948e1281b178b5b890a72e9c00979cc4 (diff) | |
| download | lwn-f41d766c34cbab024412d433a43d2d83a37e5135.tar.gz lwn-f41d766c34cbab024412d433a43d2d83a37e5135.zip | |
HID: logitech-dj: protect the paired_dj_devices access in add_djhid_dev with the lock
This protects against logi_dj_recv_add_djhid_device, adding a device to
paired_dj_devices from the delayedwork callback, racing versus
logi_dj_raw_event trying to access that device.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Diffstat (limited to 'drivers/hid/hid-logitech-dj.c')
| -rw-r--r-- | drivers/hid/hid-logitech-dj.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c index 9e5aac74808b..e9a165790482 100644 --- a/drivers/hid/hid-logitech-dj.c +++ b/drivers/hid/hid-logitech-dj.c @@ -393,12 +393,14 @@ static void logi_dj_recv_add_djhid_device(struct dj_receiver_dev *djrcv_dev, struct hid_device *dj_hiddev; struct dj_device *dj_dev; u8 device_index = workitem->device_index; + unsigned long flags; /* Device index goes from 1 to 6, we need 3 bytes to store the * semicolon, the index, and a null terminator */ unsigned char tmpstr[3]; + /* We are the only one ever adding a device, no need to lock */ if (djrcv_dev->paired_dj_devices[device_index]) { /* The device is already known. No need to reallocate it. */ dbg_hid("%s: device is already known\n", __func__); @@ -443,7 +445,9 @@ static void logi_dj_recv_add_djhid_device(struct dj_receiver_dev *djrcv_dev, dj_dev->device_index = device_index; dj_hiddev->driver_data = dj_dev; + spin_lock_irqsave(&djrcv_dev->lock, flags); djrcv_dev->paired_dj_devices[device_index] = dj_dev; + spin_unlock_irqrestore(&djrcv_dev->lock, flags); if (hid_add_device(dj_hiddev)) { dev_err(&djrcv_hdev->dev, "%s: failed adding dj_device\n", @@ -454,7 +458,9 @@ static void logi_dj_recv_add_djhid_device(struct dj_receiver_dev *djrcv_dev, return; hid_add_device_fail: + spin_lock_irqsave(&djrcv_dev->lock, flags); djrcv_dev->paired_dj_devices[device_index] = NULL; + spin_unlock_irqrestore(&djrcv_dev->lock, flags); kfree(dj_dev); dj_device_allocate_fail: hid_destroy_device(dj_hiddev); |