[PATCH v2 19/39] mm/mmap: Add shadow stack pages to memory accounting
From: Rick Edgecombe <rick.p.edgecombe@intel.com>
Date: 2022-09-29 22:33:28
Also in:
linux-arch, linux-doc, linux-mm, lkml
Subsystem:
memory management, memory mapping, the rest · Maintainers:
Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, Linus Torvalds
From: Yu-cheng Yu <redacted> Account shadow stack pages to stack memory. Signed-off-by: Yu-cheng Yu <redacted> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Cc: Kees Cook <redacted> --- v2: - Remove is_shadow_stack_mapping() and just change it to directly bitwise and VM_SHADOW_STACK. Yu-cheng v26: - Remove redundant #ifdef CONFIG_MMU. Yu-cheng v25: - Remove #ifdef CONFIG_ARCH_HAS_SHADOW_STACK for is_shadow_stack_mapping(). mm/mmap.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/mm/mmap.c b/mm/mmap.c
index f0d2e9143bd0..8569ef09614c 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c@@ -1682,6 +1682,9 @@ static inline int accountable_mapping(struct file *file, vm_flags_t vm_flags) if (file && is_file_hugepages(file)) return 0; + if (vm_flags & VM_SHADOW_STACK) + return 1; + return (vm_flags & (VM_NORESERVE | VM_SHARED | VM_WRITE)) == VM_WRITE; }
@@ -3289,6 +3292,8 @@ void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, long npages) mm->exec_vm += npages; else if (is_stack_mapping(flags)) mm->stack_vm += npages; + else if (flags & VM_SHADOW_STACK) + mm->stack_vm += npages; else if (is_data_mapping(flags)) mm->data_vm += npages; }
--
2.17.1