Linux Kernel up to 5.18.2 scsi llpfc_set_rrq_active infinite loop

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.18.2. It has been classified as critical. This affects the function llpfc_set_rrq_active of the component scsi. Performing a manipulation results in infinite loop. This vulnerability is reported as CVE-2022-49504. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.18.2. This affects the function llpfc_set_rrq_active of the component scsi. The manipulation with an unknown input leads to a infinite loop vulnerability. CWE is classifying the issue as CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Inhibit aborts if external loopback plug is inserted After running a short external loopback test, when the external loopback is removed and a normal cable inserted that is directly connected to a target device, the system oops in the llpfc_set_rrq_active() routine. When the loopback was inserted an FLOGI was transmit. As we're looped back, we receive the FLOGI request. The FLOGI is ABTS'd as we recognize the same wppn thus understand it's a loopback. However, as the ABTS sends address information the port is not set to (fffffe), the ABTS is dropped on the wire. A short 1 frame loopback test is run and completes before the ABTS times out. The looback is unplugged and the new cable plugged in, and the an FLOGI to the new device occurs and completes. Due to a mixup in ref counting the completion of the new FLOGI releases the fabric ndlp. Then the original ABTS completes and references the released ndlp generating the oops. Correct by no-op'ing the ABTS when in loopback mode (it will be dropped anyway). Added a flag to track the mode to recognize when it should be no-op'd.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2022-49504 since 02/26/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 237099 (SUSE SLES12 Security Update : kernel (SUSE-SU-2025:01600-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.18.3 eliminates this vulnerability. Applying the patch a1516930cb605caee3bc7b4f3b7994b88c0b8505/ead76d4c09b89f4c8d632648026a476a5a34fde8 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 vulnerability database at Tenable (237099). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.18.0
• 5.18.1
• 5.18.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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