Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: s390/netiucv: Fix return type of netiucv_tx() With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), indirect call targets are validated against the expected function pointer prototype to make sure the call target is valid to help mitigate ROP attacks. If they are not identical, there is a failure at run time, which manifests as either a kernel panic or thread getting killed. A proposed warning in clang aims to catch these at compile time, which reveals: drivers/s390/net/netiucv.c:1854:21: error: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Werror,-Wincompatible-function-pointer-types-strict] .ndo_start_xmit = netiucv_tx, ^~~~~~~~~~ ->ndo_start_xmit() in 'struct net_device_ops' expects a return type of 'netdev_tx_t', not 'int'. Adjust the return type of netiucv_tx() to match the prototype's to resolve the warning and potential CFI failure, should s390 select ARCH_SUPPORTS_CFI_CLANG in the future. Additionally, while in the area, remove a comment block that is no longer relevant.
References
- https://git.kernel.org/stable/c/3ac0217ca9186c2f9af9a0113a331a42aa847894
- https://git.kernel.org/stable/c/4bee3c75d5bf7c2b5dc0b520410eb40449e5da31
- https://git.kernel.org/stable/c/85d392710275355425df8618ccbebbc336f5acc5
- https://git.kernel.org/stable/c/88d86d18d7cf7e9137c95f9d212bb9fff8a1b4be
- https://git.kernel.org/stable/c/d034fa43af92fc46a81d882f46d9cc3e4ffdbbcc
- https://git.kernel.org/stable/c/dfbf0122ea1b9b3e73fa22c8ff6bd888935c54fc
- https://git.kernel.org/stable/c/e7a849f740e3576e79cba403697e916f4c3a6f12
- https://git.kernel.org/stable/c/eccc88c0efe407e579291792ad07a7dedc0f63f0
- https://git.kernel.org/stable/c/f13d870fce90f01cf930bfaffecc8185ae0be21c
FAQ
What is CVE-2022-50564?
CVE-2022-50564 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: s390/netiucv: Fix return type of netiucv_tx() With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), indirect call t...
How severe is CVE-2022-50564?
CVSS scoring is not yet available for CVE-2022-50564. Check NVD for updates.
Is there a patch for CVE-2022-50564?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.