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| author | Rafał Miłecki <rafal@milecki.pl> | 2016-12-06 00:39:33 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-12-06 08:37:41 +0100 |
| commit | 89778ba335e302a450932ce5b703c1ee6216e949 (patch) | |
| tree | ea79a345d541cd3a1a4904b987567cf3cb32bc7e /drivers/usb | |
| parent | 71158c28eb434f3fe740b1560bbd698d56f506ee (diff) | |
| download | linux-89778ba335e302a450932ce5b703c1ee6216e949.tar.gz linux-89778ba335e302a450932ce5b703c1ee6216e949.tar.bz2 linux-89778ba335e302a450932ce5b703c1ee6216e949.zip | |
usb: core: usbport: Use proper LED API to fix potential crash
Calling brightness_set manually isn't safe as some LED drivers don't
implement this callback. The best idea is to just use a proper helper
which will fallback to the brightness_set_blocking callback if needed.
This fixes:
[ 1461.761528] Unable to handle kernel NULL pointer dereference at virtual address 00000000
(...)
[ 1462.117049] Backtrace:
[ 1462.119521] [<bf228164>] (usbport_trig_port_store [ledtrig_usbport]) from [<c023f758>] (dev_attr_store+0x20/0x2c)
[ 1462.129826] r7:dcabc7c0 r6:dee0ff80 r5:00000002 r4:bf228164
[ 1462.135511] [<c023f738>] (dev_attr_store) from [<c0169310>] (sysfs_kf_write+0x48/0x4c)
[ 1462.143459] r5:00000002 r4:c023f738
[ 1462.147049] [<c01692c8>] (sysfs_kf_write) from [<c0168ab8>] (kernfs_fop_write+0xf8/0x1f8)
[ 1462.155258] r5:00000002 r4:df4a1000
[ 1462.158850] [<c01689c0>] (kernfs_fop_write) from [<c0100c78>] (__vfs_write+0x34/0x120)
[ 1462.166800] r10:00000000 r9:dee0e000 r8:c000fc24 r7:00000002 r6:dee0ff80 r5:c01689c0
[ 1462.174660] r4:df727a80
[ 1462.177204] [<c0100c44>] (__vfs_write) from [<c0101ae4>] (vfs_write+0xac/0x170)
[ 1462.184543] r9:dee0e000 r8:c000fc24 r7:dee0ff80 r6:b6f092d0 r5:df727a80 r4:00000002
[ 1462.192319] [<c0101a38>] (vfs_write) from [<c01028dc>] (SyS_write+0x4c/0xa8)
[ 1462.199396] r9:dee0e000 r8:c000fc24 r7:00000002 r6:b6f092d0 r5:df727a80 r4:df727a80
[ 1462.207174] [<c0102890>] (SyS_write) from [<c000fa60>] (ret_fast_syscall+0x0/0x3c)
[ 1462.214774] r7:00000004 r6:ffffffff r5:00000000 r4:00000000
[ 1462.220456] Code: bad PC value
[ 1462.223560] ---[ end trace 676638a3a12c7a56 ]---
Reported-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Fixes: 0f247626cbb ("usb: core: Introduce a USB port LED trigger")
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/core/ledtrig-usbport.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/drivers/usb/core/ledtrig-usbport.c b/drivers/usb/core/ledtrig-usbport.c index 3ed5162677ad..1713248ab15a 100644 --- a/drivers/usb/core/ledtrig-usbport.c +++ b/drivers/usb/core/ledtrig-usbport.c @@ -74,8 +74,7 @@ static void usbport_trig_update_count(struct usbport_trig_data *usbport_data) usbport_data->count = 0; usb_for_each_dev(usbport_data, usbport_trig_usb_dev_check); - led_cdev->brightness_set(led_cdev, - usbport_data->count ? LED_FULL : LED_OFF); + led_set_brightness(led_cdev, usbport_data->count ? LED_FULL : LED_OFF); } /*************************************** @@ -228,12 +227,12 @@ static int usbport_trig_notify(struct notifier_block *nb, unsigned long action, case USB_DEVICE_ADD: usbport_trig_add_usb_dev_ports(usb_dev, usbport_data); if (observed && usbport_data->count++ == 0) - led_cdev->brightness_set(led_cdev, LED_FULL); + led_set_brightness(led_cdev, LED_FULL); return NOTIFY_OK; case USB_DEVICE_REMOVE: usbport_trig_remove_usb_dev_ports(usbport_data, usb_dev); if (observed && --usbport_data->count == 0) - led_cdev->brightness_set(led_cdev, LED_OFF); + led_set_brightness(led_cdev, LED_OFF); return NOTIFY_OK; } |