diff options
| author | Duoming Zhou <duoming@zju.edu.cn> | 2025-12-05 11:48:31 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-12-17 14:52:12 +0100 |
| commit | 41ca62e3e21e48c2903b3b45e232cf4f2ff7434f (patch) | |
| tree | 476272d9ce0530ff6353a6a64ea57772fdd7fdff | |
| parent | 36cc7e09df9e43db21b46519b740145410dd9f4a (diff) | |
usb: phy: fsl-usb: Fix use-after-free in delayed work during device removal
The delayed work item otg_event is initialized in fsl_otg_conf() and
scheduled under two conditions:
1. When a host controller binds to the OTG controller.
2. When the USB ID pin state changes (cable insertion/removal).
A race condition occurs when the device is removed via fsl_otg_remove():
the fsl_otg instance may be freed while the delayed work is still pending
or executing. This leads to use-after-free when the work function
fsl_otg_event() accesses the already freed memory.
The problematic scenario:
(detach thread) | (delayed work)
fsl_otg_remove() |
kfree(fsl_otg_dev) //FREE| fsl_otg_event()
| og = container_of(...) //USE
| og-> //USE
Fix this by calling disable_delayed_work_sync() in fsl_otg_remove()
before deallocating the fsl_otg structure. This ensures the delayed work
is properly canceled and completes execution prior to memory deallocation.
This bug was identified through static analysis.
Fixes: 0807c500a1a6 ("USB: add Freescale USB OTG Transceiver driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://patch.msgid.link/20251205034831.12846-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/phy/phy-fsl-usb.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-fsl-usb.c b/drivers/usb/phy/phy-fsl-usb.c index 40ac68e52cee..e266a47c4d48 100644 --- a/drivers/usb/phy/phy-fsl-usb.c +++ b/drivers/usb/phy/phy-fsl-usb.c @@ -988,6 +988,7 @@ static void fsl_otg_remove(struct platform_device *pdev) { struct fsl_usb2_platform_data *pdata = dev_get_platdata(&pdev->dev); + disable_delayed_work_sync(&fsl_otg_dev->otg_event); usb_remove_phy(&fsl_otg_dev->phy); free_irq(fsl_otg_dev->irq, fsl_otg_dev); |