CVE-2025-40337

Summary

In the Linux kernel, the following vulnerability has been resolved:

net: stmmac: Correctly handle Rx checksum offload errors

The stmmac_rx function would previously set skb->ip_summed to CHECKSUM_UNNECESSARY if hardware checksum offload (CoE) was enabled and the packet was of a known IP ethertype.

However, this logic failed to check if the hardware had actually reported a checksum error. The hardware status, indicating a header or payload checksum failure, was being ignored at this stage. This could cause corrupt packets to be passed up the network stack as valid.

This patch corrects the logic by checking the csum_none status flag, which is set when the hardware reports a checksum error. If this flag is set, skb->ip_summed is now correctly set to CHECKSUM_NONE, ensuring the kernel's network stack will perform its own validation and properly handle the corrupt packet.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux3c20f72f9108b2fcf30ec63d8a4203736c01ccd0 < 63fbe0e6413279d5ea5842e2423e351ded547683affected
LinuxLinux3c20f72f9108b2fcf30ec63d8a4203736c01ccd0 < 719fcdf29051f7471d5d433475af76219019d33daffected
LinuxLinux3c20f72f9108b2fcf30ec63d8a4203736c01ccd0 < 1aa319e0f12d2d761a31556b82a5852c98eb0beaaffected
LinuxLinux3c20f72f9108b2fcf30ec63d8a4203736c01ccd0 < ee0aace5f844ef59335148875d05bec8764e71e8affected
LinuxLinux3.2affected
LinuxLinux0 < 3.2unaffected
LinuxLinux6.6.117 <= 6.6.*unaffected
LinuxLinux6.12.58 <= 6.12.*unaffected
LinuxLinux6.17.8 <= 6.17.*unaffected
LinuxLinux6.18 <= *unaffected

Weaknesses

References