Commit 4c4eb3ec authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Peter Zijlstra
Browse files

x86/modules: Set VM_FLUSH_RESET_PERMS in module_alloc() 



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: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111143.406703869@infradead.org
parent 2cb15faa

arch/x86/kernel/ftrace.c

+0 −2
Original line number Diff line number Diff line
@@ -413,8 +413,6 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) 
	/* 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);

arch/x86/kernel/kprobes/core.c

+0 −1
Original line number Diff line number Diff line
@@ -414,7 +414,6 @@ 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.

arch/x86/kernel/module.c

+5 −4
Original line number Diff line number Diff line
@@ -75,9 +75,10 @@ void *module_alloc(unsigned long size) 


	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_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;