Linux Kernel up to 6.1.102/6.6.43/6.10.2 rcar_pcie_wakeup state issue

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.102/6.6.43/6.10.2. It has been classified as problematic. The impacted element is the function rcar_pcie_wakeup. The manipulation leads to state issue. This vulnerability is referenced as CVE-2024-43876. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.102/6.6.43/6.10.2 and classified as problematic. This issue affects the function rcar_pcie_wakeup. The manipulation with an unknown input leads to a state issue vulnerability. Using CWE to declare the problem leads to CWE-371. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: PCI: rcar: Demote WARN() to dev_warn_ratelimited() in rcar_pcie_wakeup() Avoid large backtrace, it is sufficient to warn the user that there has been a link problem. Either the link has failed and the system is in need of maintenance, or the link continues to work and user has been informed. The message from the warning can be looked up in the sources. This makes an actual link issue less verbose. First of all, this controller has a limitation in that the controller driver has to assist the hardware with transition to L1 link state by writing L1IATN to PMCTRL register, the L1 and L0 link state switching is not fully automatic on this controller. In case of an ASMedia ASM1062 PCIe SATA controller which does not support ASPM, on entry to suspend or during platform pm_test, the SATA controller enters D3hot state and the link enters L1 state. If the SATA controller wakes up before rcar_pcie_wakeup() was called and returns to D0, the link returns to L0 before the controller driver even started its transition to L1 link state. At this point, the SATA controller did send an PM_ENTER_L1 DLLP to the PCIe controller and the PCIe controller received it, and the PCIe controller did set PMSR PMEL1RX bit. Once rcar_pcie_wakeup() is called, if the link is already back in L0 state and PMEL1RX bit is set, the controller driver has no way to determine if it should perform the link transition to L1 state, or treat the link as if it is in L0 state. Currently the driver attempts to perform the transition to L1 link state unconditionally, which in this specific case fails with a PMSR L1FAEG poll timeout, however the link still works as it is already back in L0 state. Reduce this warning verbosity. In case the link is really broken, the rcar_pcie_config_access() would fail, otherwise it will succeed and any system with this controller and ASM1062 can suspend without generating a backtrace.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2024-43876 since 08/17/2024. The exploitation is known to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 212724 (Ubuntu 22.04 LTS / 24.04 LTS : Linux kernel vulnerabilities (USN-7154-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.103, 6.6.44 or 6.10.3 eliminates this vulnerability. Applying the patch 2ae4769332df/526a877c6273/3ff3bdde950f/c93637e6a4c4 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (212724) and CERT Bund (WID-SEC-2024-1888). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• Kyocera Printer
• IBM Security Guardium
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Open Source Linux Kernel
• IBM QRadar SIEM
• IBM DB2
• Dell PowerProtect Data Domain
• Dell PowerProtect Data Domain Management Center
• Dell PowerProtect Data Domain OS
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.102
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.10.0
• 6.10.1
• 6.10.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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