Medium · published April 3, 2026
In the Linux kernel, the following vulnerability has been resolved:
net: usb: aqc111: Do not perform PM inside suspend callback
syzbot reports "task hung in rpm_resume"
This is caused by aqc111_suspend calling
the PM variant of its write_cmd routine.
The simplified call trace looks like this:
rpm_suspend()
usb_suspend_both() - here udev->dev.power.runtime_status == RPM_SUSPENDING
aqc111_suspend() - called for the usb device interface
aqc111_write32_cmd()
usb_autopm_get_interface()
pm_runtime_resume_and_get()
rpm_resume() - here we call rpm_resume() on our parent
rpm_resume() - Here we wait for a status change that will never happen.
At this point we block another task which holds
rtnl_lock and locks up the whole networking stack.
Fix this by replacing the write_cmd calls with their _nopm variants
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 5.0.1, < 5.10.253 | 5.10.253 |
| linux/linux_kernel | ≥ 5.11, < 5.15.203 | 5.15.203 |
| linux/linux_kernel | ≥ 5.16, < 6.1.167 | 6.1.167 |
| linux/linux_kernel | ≥ 6.2, < 6.6.130 | 6.6.130 |
| linux/linux_kernel | ≥ 6.7, < 6.12.78 | 6.12.78 |
| linux/linux_kernel | ≥ 6.13, < 6.18.20 | 6.18.20 |
| linux/linux_kernel | ≥ 6.19, < 6.19.10 | 6.19.10 |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |