Linux Kernel up to 7.2.5 cxgb4 write_tpt_entry double free

Summaryinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 7.2.5. This affects the function write_tpt_entry of the component cxgb4. Such manipulation leads to double free. This vulnerability is listed as CVE-2026-90417. The attack may be performed from remote. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.2.5. It has been rated as very critical. Affected by this issue is the function write_tpt_entry of the component cxgb4. The manipulation with an unknown input leads to a double free vulnerability. Using CWE to declare the problem leads to CWE-415. The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: RDMA/cxgb4: Fix dereg_skb leak and double free in write_tpt_entry() When the device is in the fatal error state, write_tpt_entry() returns -EIO before handing the caller's preallocated skb to the transmit path; its allocation-failure returns do the same. c4iw_dereg_mr() ignores the error and frees mhp, leaking mhp->dereg_skb. c4iw_get_dma_mr() instead frees the skb a second time after dereg_mem() already consumed it, a double free. Make write_tpt_entry() the sole owner of a non-NULL skb, freeing it on every return preceding handoff to c4iw_ofld_send(): fatal error, tpt and stag allocation failure. c4iw_ofld_send() consumes the skb on success and error alike, so drop the redundant kfree_skb() in c4iw_get_dma_mr() after dereg_mem().

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2026-90417 since 09/11/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 09/17/2026).

Upgrading to version 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch 6b15fc9bc117fb6597fa1c2cc30284aafe71101c/373f3716a2de7adc739269ebb4d87e5bf4dc180c is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 7.2.0
• 7.2.1
• 7.2.2
• 7.2.3
• 7.2.4
• 7.2.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

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