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authorLiam R. Howlett <Liam.Howlett@Oracle.com>2023-01-20 19:26:18 +0300
committerAndrew Morton <akpm@linux-foundation.org>2023-02-10 03:51:33 +0300
commit2286a6914c776ec34cd97e4573b1466d055cb9de (patch)
tree604494992e21b5f745268b64cdc3255d7f46496f /mm/mprotect.c
parent11a9b90274f6a50f7877a61c8e82dd3c845ff1dd (diff)
downloadlinux-2286a6914c776ec34cd97e4573b1466d055cb9de.tar.xz
mm: change mprotect_fixup to vma iterator
Use the vma iterator so that the iterator can be invalidated or updated to avoid each caller doing so. Link: https://lkml.kernel.org/r/20230120162650.984577-18-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/mprotect.c')
-rw-r--r--mm/mprotect.c47
1 files changed, 22 insertions, 25 deletions
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 6a22f3ad9b84..39b6335b8813 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -585,9 +585,9 @@ static const struct mm_walk_ops prot_none_walk_ops = {
};
int
-mprotect_fixup(struct mmu_gather *tlb, struct vm_area_struct *vma,
- struct vm_area_struct **pprev, unsigned long start,
- unsigned long end, unsigned long newflags)
+mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
+ struct vm_area_struct *vma, struct vm_area_struct **pprev,
+ unsigned long start, unsigned long end, unsigned long newflags)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long oldflags = vma->vm_flags;
@@ -642,7 +642,7 @@ mprotect_fixup(struct mmu_gather *tlb, struct vm_area_struct *vma,
* First try to merge with previous and/or next vma.
*/
pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
- *pprev = vma_merge(mm, *pprev, start, end, newflags,
+ *pprev = vmi_vma_merge(vmi, mm, *pprev, start, end, newflags,
vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma),
vma->vm_userfaultfd_ctx, anon_vma_name(vma));
if (*pprev) {
@@ -654,13 +654,13 @@ mprotect_fixup(struct mmu_gather *tlb, struct vm_area_struct *vma,
*pprev = vma;
if (start != vma->vm_start) {
- error = split_vma(mm, vma, start, 1);
+ error = vmi_split_vma(vmi, mm, vma, start, 1);
if (error)
goto fail;
}
if (end != vma->vm_end) {
- error = split_vma(mm, vma, end, 0);
+ error = vmi_split_vma(vmi, mm, vma, end, 0);
if (error)
goto fail;
}
@@ -709,7 +709,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
const bool rier = (current->personality & READ_IMPLIES_EXEC) &&
(prot & PROT_READ);
struct mmu_gather tlb;
- MA_STATE(mas, &current->mm->mm_mt, 0, 0);
+ struct vma_iterator vmi;
start = untagged_addr(start);
@@ -741,8 +741,8 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
if ((pkey != -1) && !mm_pkey_is_allocated(current->mm, pkey))
goto out;
- mas_set(&mas, start);
- vma = mas_find(&mas, ULONG_MAX);
+ vma_iter_init(&vmi, current->mm, start);
+ vma = vma_find(&vmi, end);
error = -ENOMEM;
if (!vma)
goto out;
@@ -765,18 +765,22 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
}
}
+ prev = vma_prev(&vmi);
if (start > vma->vm_start)
prev = vma;
- else
- prev = mas_prev(&mas, 0);
tlb_gather_mmu(&tlb, current->mm);
- for (nstart = start ; ; ) {
+ nstart = start;
+ tmp = vma->vm_start;
+ for_each_vma_range(vmi, vma, end) {
unsigned long mask_off_old_flags;
unsigned long newflags;
int new_vma_pkey;
- /* Here we know that vma->vm_start <= nstart < vma->vm_end. */
+ if (vma->vm_start != tmp) {
+ error = -ENOMEM;
+ break;
+ }
/* Does the application expect PROT_READ to imply PROT_EXEC */
if (rier && (vma->vm_flags & VM_MAYEXEC))
@@ -824,25 +828,18 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
break;
}
- error = mprotect_fixup(&tlb, vma, &prev, nstart, tmp, newflags);
+ error = mprotect_fixup(&vmi, &tlb, vma, &prev, nstart, tmp, newflags);
if (error)
break;
nstart = tmp;
-
- if (nstart < prev->vm_end)
- nstart = prev->vm_end;
- if (nstart >= end)
- break;
-
- vma = find_vma(current->mm, prev->vm_end);
- if (!vma || vma->vm_start != nstart) {
- error = -ENOMEM;
- break;
- }
prot = reqprot;
}
tlb_finish_mmu(&tlb);
+
+ if (vma_iter_end(&vmi) < end)
+ error = -ENOMEM;
+
out:
mmap_write_unlock(current->mm);
return error;