Linux Kernel up to 5.10.37/5.11.21/5.12.4 xprtrdma rpcrdma_post_recvs denial of service

Summaryinfo

A vulnerability marked as problematic has been reported in Linux Kernel up to 5.10.37/5.11.21/5.12.4. Affected by this vulnerability is the function rpcrdma_post_recvs of the component xprtrdma. The manipulation leads to denial of service. This vulnerability is referenced as CVE-2021-47001. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 5.10.37/5.11.21/5.12.4 (Operating System). This issue affects the function rpcrdma_post_recvs of the component xprtrdma. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix cwnd update ordering After a reconnect, the reply handler is opening the cwnd (and thus enabling more RPC Calls to be sent) /before/ rpcrdma_post_recvs() can post enough Receive WRs to receive their replies. This causes an RNR and the new connection is lost immediately. The race is most clearly exposed when KASAN and disconnect injection are enabled. This slows down rpcrdma_rep_create() enough to allow the send side to post a bunch of RPC Calls before the Receive completion handler can invoke ib_post_recv().

The weakness was published 02/28/2024. It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2021-47001 since 02/27/2024. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 213100 (Ubuntu 18.04 LTS / 20.04 LTS : Linux kernel vulnerabilities (USN-7173-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.38, 5.11.22, 5.12.5 or 5.13 eliminates this vulnerability. Applying the patch eddae8be7944/8834ecb5df22/19b5fa9489b5/35d8b10a2588 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 (213100). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.11.0
• 5.11.1
• 5.11.2
• 5.11.3
• 5.11.4
• 5.11.5
• 5.11.6
• 5.11.7
• 5.11.8
• 5.11.9
• 5.11.10
• 5.11.11
• 5.11.12
• 5.11.13
• 5.11.14
• 5.11.15
• 5.11.16
• 5.11.17
• 5.11.18
• 5.11.19
• 5.11.20
• 5.11.21
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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