CVE-2026-68434

Description

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms Commit b1b4efea05a5 ("serial: 8250_mid: Disable DMA for selected platforms") replaced the dnv_board setup and exit callbacks with PTR_IF(false, ...), which evaluates to NULL. However, the three call sites in mid8250_probe() and mid8250_remove() unconditionally dereference these function pointers without NULL checks, causing a NULL pointer dereference (kernel oops) on any Denverton (DNV), Ice Lake Xeon D (ICX-D/CDF), or Snowridge (SNR) platform. Fix this by adding the missing NULL checks before calling the setup and exit callbacks.

References

• https://git.kernel.org/stable/c/1096397c31f6bffa95e77bdd18fbca085be83e10
• https://git.kernel.org/stable/c/600dcd548fb2b00a69f447684f52ba45d5a3540e
• https://git.kernel.org/stable/c/7fb13fd7e9a59a37cd911efff83abe19e3ee029d
• https://git.kernel.org/stable/c/8cbad52ccfa6a7f089cfab34979bc6cc3bff25be
• https://git.kernel.org/stable/c/b2a3eeb57ba24f8a0e34a69d40adcc63e5b9ca56