driver core: Avoid warning when removing a device while its supplier is unbinding
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 5.7, 5.8, 6.6.160, 6.12.114, 6.18.53
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: driver core: Avoid warning when removing a device while its supplier is unbinding During driver removal, the following warning can appear: WARNING: CPU: 1 PID: 139 at drivers/base/core.c:1497 __device_links_no_driver+0xcc/0xfc ... Call trace: __device_links_no_driver+0xcc/0xfc (P) device_links_driver_cleanup+0xa8/0xf0 device_release_driver_internal+0x208/0x23c device_links_unbind_consumers+0xe0/0x108 device_release_driver_internal+0xec/0x23c device_links_unbind_consumers+0xe0/0x108 device_release_driver_internal+0xec/0x23c device_links_unbind_consumers+0xe0/0x108 device_release_driver_internal+0xec/0x23c driver_detach+0xa0/0x12c bus_remove_driver+0x6c/0xbc driver_unregister+0x30/0x60 pci_unregister_driver+0x20/0x9c lan966x_pci_driver_exit+0x18/0xa90 [lan966x_pci] This warning is triggered when a consumer is removed because the links status of its supplier is not DL_DEV_DRIVER_BOUND and the link flag DL_FLAG_SYNC_STATE_ONLY is not set. The topology in terms of consumers/suppliers used was the following (consumer ---> supplier): i2c -----------> OIC ----> PCI device | ^ | | +---> pinctrl ---+ When the PCI device is removed, the OIC (interrupt controller) has to be removed. In order to remove the OIC, pinctrl and i2c need to be removed and to remove pinctrl, i2c need to be removed. The removal order is: 1) i2c 2) pinctrl 3) OIC 4) PCI device In details, the removal sequence is the following (with 0000:01:00.0 the PCI device): driver_detach: call device_release_driver_internal(0000:01:00.0)... device_links_busy(0000:01:00.0): links->status = DL_DEV_UNBINDING device_links_unbind_consumers(0000:01:00.0): 0000:01:00.0--oic link->status = DL_STATE_SUPPLIER_UNBIND call device_release_driver_internal(oic)... device_links_busy(oic): links->status = DL_DEV_UNBINDING device_links_unbind_consumers(oic): oic--pinctrl link->status = DL_STATE_SUPPLIER_UNBIND call device_release_driver_internal(pinctrl)... device_links_busy(pinctrl): links->status = DL_DEV_UNBINDING device_links_unbind_consumers(pinctrl): pinctrl--i2c link->status = DL_STATE_SUPPLIER_UNBIND call device_release_driver_internal(i2c)... device_links_busy(i2c): links->status = DL_DEV_UNBINDING __device_links_no_driver(i2c)... pinctrl--i2c link->status is DL_STATE_SUPPLIER_UNBIND oic--i2c link->status is DL_STATE_ACTIVE oic--i2c link->supplier->links.status is DL_DEV_UNBINDING The warning is triggered by the i2c removal because the OIC (supplier) links status is not DL_DEV_DRIVER_BOUND. Its links status is indeed set to DL_DEV_UNBINDING. It is perfectly legit to have the links status set to DL_DEV_UNBINDING in that case. Indeed we had started to unbind the OIC which triggered the consumer unbinding and didn't finish yet when the i2c is unbound. Avoid the warning when the supplier links status is set to DL_DEV_UNBINDING and thus support this removal sequence without any warnings.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 8c3e315d4296421cd26b3300ee0ac117f0877f20 · fixed in d5eb39d6178ca88db706c7b82dcd19a77f30aa9e; From 8c3e315d4296421cd26b3300ee0ac117f0877f20 · fixed in da22e4bce2a8cbed32dcda407b7d06cb5feec8e3; From 8c3e315d4296421cd26b3300ee0ac117f0877f20 · fixed in 73ea4ec0ec46d12558a61842b474e7dd63538edc; From 8c3e315d4296421cd26b3300ee0ac117f0877f20 · fixed in 36d74f17e03f7e60e1b08fbe16cfad6e69cc3aa9; From 5.6.19 · fixed in 5.7; From 5.7.3 · fixed in 5.8
- Linux Linux
5.8
- KernelLinux
From 5.8.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.114; From 6.13.0 · fixed in 6.18.53