mm/mremap: fix unaccount of memory on vma_merge() failure

Fix mremap so that only accounted memory is unaccounted if the mapping is
expandable but vma_merge() fails.

Link: https://lkml.kernel.org/r/20230830004549.16131-1-anthony.yznaga@oracle.com
Fixes: fdbef61491 ("mm/mremap: don't account pages in vma_to_resize()")
Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Anthony Yznaga 2023-08-29 17:45:49 -07:00 committed by Andrew Morton
parent b6afcb94ce
commit 954652b9f3

View File

@ -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;
}