CVE-2024-50133

In the Linux kernel, the following vulnerability has been resolved: LoongArch: Don't crash in stack_top() for tasks without vDSO Not all tasks have a vDSO mapped, for example kthreads never do. If such a task ever ends up calling stack_top(), it will derefence the NULL vdso pointer and crash. This can for example happen when using kunit: [ ] stack_top+0x58/0xa8 [ ] arch_pick_mmap_layout+0x164/0x220 [ ] kunit_vm_mmap_init+0x108/0x12c [ ] __kunit_add_resource+0x38/0x8c [ ] kunit_vm_mmap+0x88/0xc8 [ ] usercopy_test_init+0xbc/0x25c [ ] kunit_try_run_case+0x5c/0x184 [ ] kunit_generic_run_threadfn_adapter+0x24/0x48 [ ] kthread+0xc8/0xd4 [ ] ret_from_kernel_thread+0xc/0xa4