linux/lib/kunit/user_alloc.c
Kees Cook 4d6cf24832 kunit/usercopy: Disable testing on !CONFIG_MMU
Since arch_pick_mmap_layout() is an inline for non-MMU systems, disable
this test there.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202406160505.uBge6TMY-lkp@intel.com/
Signed-off-by: Kees Cook <kees@kernel.org>
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-07-02 10:11:40 -06:00

118 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* KUnit userspace memory allocation resource management.
*/
#include <kunit/resource.h>
#include <kunit/test.h>
#include <linux/kthread.h>
#include <linux/mm.h>
struct kunit_vm_mmap_resource {
unsigned long addr;
size_t size;
};
/* vm_mmap() arguments */
struct kunit_vm_mmap_params {
struct file *file;
unsigned long addr;
unsigned long len;
unsigned long prot;
unsigned long flag;
unsigned long offset;
};
/* Create and attach a new mm if it doesn't already exist. */
static int kunit_attach_mm(void)
{
struct mm_struct *mm;
if (current->mm)
return 0;
/* arch_pick_mmap_layout() is only sane with MMU systems. */
if (!IS_ENABLED(CONFIG_MMU))
return -EINVAL;
mm = mm_alloc();
if (!mm)
return -ENOMEM;
/* Define the task size. */
mm->task_size = TASK_SIZE;
/* Make sure we can allocate new VMAs. */
arch_pick_mmap_layout(mm, &current->signal->rlim[RLIMIT_STACK]);
/* Attach the mm. It will be cleaned up when the process dies. */
kthread_use_mm(mm);
return 0;
}
static int kunit_vm_mmap_init(struct kunit_resource *res, void *context)
{
struct kunit_vm_mmap_params *p = context;
struct kunit_vm_mmap_resource vres;
int ret;
ret = kunit_attach_mm();
if (ret)
return ret;
vres.size = p->len;
vres.addr = vm_mmap(p->file, p->addr, p->len, p->prot, p->flag, p->offset);
if (!vres.addr)
return -ENOMEM;
res->data = kmemdup(&vres, sizeof(vres), GFP_KERNEL);
if (!res->data) {
vm_munmap(vres.addr, vres.size);
return -ENOMEM;
}
return 0;
}
static void kunit_vm_mmap_free(struct kunit_resource *res)
{
struct kunit_vm_mmap_resource *vres = res->data;
/*
* Since this is executed from the test monitoring process,
* the test's mm has already been torn down. We don't need
* to run vm_munmap(vres->addr, vres->size), only clean up
* the vres.
*/
kfree(vres);
res->data = NULL;
}
unsigned long kunit_vm_mmap(struct kunit *test, struct file *file,
unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flag,
unsigned long offset)
{
struct kunit_vm_mmap_params params = {
.file = file,
.addr = addr,
.len = len,
.prot = prot,
.flag = flag,
.offset = offset,
};
struct kunit_vm_mmap_resource *vres;
vres = kunit_alloc_resource(test,
kunit_vm_mmap_init,
kunit_vm_mmap_free,
GFP_KERNEL,
&params);
if (vres)
return vres->addr;
return 0;
}
EXPORT_SYMBOL_GPL(kunit_vm_mmap);
MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);