CVE-2024-41021

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> s390/mm: Fix VM_FAULT_HWPOISON handling in do_exception()<br /> <br /> There is no support for HWPOISON, MEMORY_FAILURE, or ARCH_HAS_COPY_MC on<br /> s390. Therefore we do not expect to see VM_FAULT_HWPOISON in<br /> do_exception().<br /> <br /> However, since commit af19487f00f3 ("mm: make PTE_MARKER_SWAPIN_ERROR more<br /> general"), it is possible to see VM_FAULT_HWPOISON in combination with<br /> PTE_MARKER_POISONED, even on architectures that do not support HWPOISON<br /> otherwise. In this case, we will end up on the BUG() in do_exception().<br /> <br /> Fix this by treating VM_FAULT_HWPOISON the same as VM_FAULT_SIGBUS, similar<br /> to x86 when MEMORY_FAILURE is not configured. Also print unexpected fault<br /> flags, for easier debugging.<br /> <br /> Note that VM_FAULT_HWPOISON_LARGE is not expected, because s390 cannot<br /> support swap entries on other levels than PTE level.