[PATCH v2 05/59] x86/modules: Set VM_FLUSH_RESET_PERMS in module_alloc()

Peter Zijlstra posted 59 patches 3 years, 7 months ago
There is a newer version of this series
[PATCH v2 05/59] x86/modules: Set VM_FLUSH_RESET_PERMS in module_alloc()
Posted by Peter Zijlstra 3 years, 7 months ago
From: Thomas Gleixner <tglx@linutronix.de>

Instead of resetting permissions all over the place when freeing module
memory tell the vmalloc code to do so. Avoids the exercise for the next
upcoming user.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 arch/x86/kernel/ftrace.c       |    2 --
 arch/x86/kernel/kprobes/core.c |    1 -
 arch/x86/kernel/module.c       |    9 +++++----
 3 files changed, 5 insertions(+), 7 deletions(-)

--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -413,8 +413,6 @@ create_trampoline(struct ftrace_ops *ops
 	/* ALLOC_TRAMP flags lets us know we created it */
 	ops->flags |= FTRACE_OPS_FL_ALLOC_TRAMP;
 
-	set_vm_flush_reset_perms(trampoline);
-
 	if (likely(system_state != SYSTEM_BOOTING))
 		set_memory_ro((unsigned long)trampoline, npages);
 	set_memory_x((unsigned long)trampoline, npages);
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -416,7 +416,6 @@ void *alloc_insn_page(void)
 	if (!page)
 		return NULL;
 
-	set_vm_flush_reset_perms(page);
 	/*
 	 * First make the page read-only, and only then make it executable to
 	 * prevent it from being W+X in between.
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -74,10 +74,11 @@ void *module_alloc(unsigned long size)
 		return NULL;
 
 	p = __vmalloc_node_range(size, MODULE_ALIGN,
-				    MODULES_VADDR + get_module_load_offset(),
-				    MODULES_END, gfp_mask,
-				    PAGE_KERNEL, VM_DEFER_KMEMLEAK, NUMA_NO_NODE,
-				    __builtin_return_address(0));
+				 MODULES_VADDR + get_module_load_offset(),
+				 MODULES_END, gfp_mask, PAGE_KERNEL,
+				 VM_FLUSH_RESET_PERMS | VM_DEFER_KMEMLEAK,
+				 NUMA_NO_NODE, __builtin_return_address(0));
+
 	if (p && (kasan_alloc_module_shadow(p, size, gfp_mask) < 0)) {
 		vfree(p);
 		return NULL;