diff options
Diffstat (limited to 'mm/mmap.c')
-rw-r--r-- | mm/mmap.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 1fc0e92be4ba..e71d2d471416 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1781,7 +1781,11 @@ unsigned long mmap_region(struct file *file, unsigned long addr, merge = vma_merge(mm, prev, vma->vm_start, vma->vm_end, vma->vm_flags, NULL, vma->vm_file, vma->vm_pgoff, NULL, NULL_VM_UFFD_CTX); if (merge) { - fput(file); + /* ->mmap() can change vma->vm_file and fput the original file. So + * fput the vma->vm_file here or we would add an extra fput for file + * and cause general protection fault ultimately. + */ + fput(vma->vm_file); vm_area_free(vma); vma = merge; /* Update vm_flags and possible addr to pick up the change. We don't @@ -1812,6 +1816,15 @@ unsigned long mmap_region(struct file *file, unsigned long addr, vma_set_anonymous(vma); } + /* Allow architectures to sanity-check the vm_flags */ + if (!arch_validate_flags(vma->vm_flags)) { + error = -EINVAL; + if (file) + goto unmap_and_free_vma; + else + goto free_vma; + } + vma_link(mm, vma, prev, rb_link, rb_parent); /* Once vma denies write, undo our temporary denial count */ if (file) { |