diff --git a/mm/internal.h b/mm/internal.h index 85ac9c6a13933065023c106abc6bc34de9aa72cc..16a4a9aece3043565628eeaf79f26b8d2f168b92 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -64,6 +64,13 @@ void page_writeback_init(void); */ int mmap_file(struct file *file, struct vm_area_struct *vma); +/* + * If the VMA has a close hook then close it, and since closing it might leave + * it in an inconsistent state which makes the use of any hooks suspect, clear + * them down by installing dummy empty hooks. + */ +void vma_close(struct vm_area_struct *vma); + static inline void *folio_raw_mapping(struct folio *folio) { unsigned long mapping = (unsigned long)folio->mapping; diff --git a/mm/mmap.c b/mm/mmap.c index bf2f1ca87bef2e8bd64b861ea0a27a78edce352e..4bfec4df51c2d0ba4a8fbfabdfcf5023e4e035a3 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -136,8 +136,7 @@ void unlink_file_vma(struct vm_area_struct *vma) static void remove_vma(struct vm_area_struct *vma) { might_sleep(); - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); if (vma->vm_file) fput(vma->vm_file); mpol_put(vma_policy(vma)); @@ -2388,8 +2387,7 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma, new->vm_start = new->vm_end; new->vm_pgoff = 0; /* Clean everything up if vma_adjust failed. */ - if (new->vm_ops && new->vm_ops->close) - new->vm_ops->close(new); + vma_close(new); if (new->vm_file) fput(new->vm_file); unlink_anon_vmas(new); @@ -2885,8 +2883,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, return addr; close_and_free_vma: - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); unmap_and_free_vma: fput(vma->vm_file); vma->vm_file = NULL; @@ -3376,8 +3373,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, return new_vma; out_vma_link: - if (new_vma->vm_ops && new_vma->vm_ops->close) - new_vma->vm_ops->close(new_vma); + vma_close(new_vma); if (new_vma->vm_file) fput(new_vma->vm_file); diff --git a/mm/nommu.c b/mm/nommu.c index f09e798a44166aaa01ba248d8ed670e79b8fd658..e0428fa575269581c237adb2a0f4e3ce036f9a79 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -650,8 +650,7 @@ static int delete_vma_from_mm(struct vm_area_struct *vma) */ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) { - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); if (vma->vm_file) fput(vma->vm_file); put_nommu_region(vma->vm_region); diff --git a/mm/util.c b/mm/util.c index 15f1970da665dfd52330d393d54bd445403ba679..d3a2877c176f98c67f282e60612532592398c900 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1121,6 +1121,21 @@ int mmap_file(struct file *file, struct vm_area_struct *vma) return err; } +void vma_close(struct vm_area_struct *vma) +{ + static const struct vm_operations_struct dummy_vm_ops = {}; + + if (vma->vm_ops && vma->vm_ops->close) { + vma->vm_ops->close(vma); + + /* + * The mapping is in an inconsistent state, and no further hooks + * may be invoked upon it. + */ + vma->vm_ops = &dummy_vm_ops; + } +} + #ifdef CONFIG_PRINTK /** * mem_dump_obj - Print available provenance information