| Message ID | 20230830004549.16131-1-anthony.yznaga@oracle.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/mremap: fix unaccount of memory on vma_merge() failure | expand |
On Tue, Aug 29, 2023 at 8:46 PM Anthony Yznaga <anthony.yznaga@oracle.com> wrote: > > Fix mremap so that only accounted memory is unaccounted if the > mapping is expandable but vma_merge() fails. > > Fixes: fdbef6149135 ("mm/mremap: don't account pages in vma_to_resize()") > Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com> Looks correct to me. Acked-by: Brian Geffon <bgeffon@google.com> > --- > mm/mremap.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/mm/mremap.c b/mm/mremap.c > index 056478c106ee..07cdb04d4ab5 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -1037,12 +1037,14 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, > pgoff_t extension_pgoff = vma->vm_pgoff + > ((extension_start - vma->vm_start) >> PAGE_SHIFT); > VMA_ITERATOR(vmi, mm, extension_start); > + long charged = 0; > > if (vma->vm_flags & VM_ACCOUNT) { > if (security_vm_enough_memory_mm(mm, pages)) { > ret = -ENOMEM; > goto out; > } > + charged = pages; > } > > /* > @@ -1058,7 +1060,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, > vma->vm_file, extension_pgoff, vma_policy(vma), > vma->vm_userfaultfd_ctx, anon_vma_name(vma)); > if (!vma) { > - vm_unacct_memory(pages); > + vm_unacct_memory(charged); > ret = -ENOMEM; > goto out; > } > -- > 2.39.3 >
diff --git a/mm/mremap.c b/mm/mremap.c index 056478c106ee..07cdb04d4ab5 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -1037,12 +1037,14 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, pgoff_t extension_pgoff = vma->vm_pgoff + ((extension_start - vma->vm_start) >> PAGE_SHIFT); VMA_ITERATOR(vmi, mm, extension_start); + long charged = 0; if (vma->vm_flags & VM_ACCOUNT) { if (security_vm_enough_memory_mm(mm, pages)) { ret = -ENOMEM; goto out; } + charged = pages; } /* @@ -1058,7 +1060,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, vma->vm_file, extension_pgoff, vma_policy(vma), vma->vm_userfaultfd_ctx, anon_vma_name(vma)); if (!vma) { - vm_unacct_memory(pages); + vm_unacct_memory(charged); ret = -ENOMEM; goto out; }
Fix mremap so that only accounted memory is unaccounted if the mapping is expandable but vma_merge() fails. Fixes: fdbef6149135 ("mm/mremap: don't account pages in vma_to_resize()") Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com> --- mm/mremap.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)