From 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 2 Sep 2026 15:31:14 -0700 Subject: treewide: refresh kmalloc_obj() conversions This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook --- arch/powerpc/mm/pageattr.c | 127 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 arch/powerpc/mm/pageattr.c (limited to 'arch/powerpc/mm/pageattr.c') diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c new file mode 100644 index 000000000..ac22bf280 --- /dev/null +++ b/arch/powerpc/mm/pageattr.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * MMU-generic set_memory implementation for powerpc + * + * Copyright 2019-2021, IBM Corporation. + */ + +#include +#include +#include + +#include +#include +#include + +#include + +static pte_basic_t pte_update_delta(pte_t *ptep, unsigned long addr, + unsigned long old, unsigned long new) +{ + return pte_update(&init_mm, addr, ptep, old & ~new, new & ~old, 0); +} + +/* + * Updates the attributes of a page atomically. + * + * This sequence is safe against concurrent updates, and also allows updating the + * attributes of a page currently being executed or accessed. + */ +static int change_page_attr(pte_t *ptep, unsigned long addr, void *data) +{ + long action = (long)data; + + addr &= PAGE_MASK; + /* modify the PTE bits as desired */ + switch (action) { + case SET_MEMORY_RO: + /* Don't clear DIRTY bit */ + pte_update_delta(ptep, addr, _PAGE_KERNEL_RW & ~_PAGE_DIRTY, _PAGE_KERNEL_RO); + break; + case SET_MEMORY_ROX: + /* Don't clear DIRTY bit */ + pte_update_delta(ptep, addr, _PAGE_KERNEL_RW & ~_PAGE_DIRTY, _PAGE_KERNEL_ROX); + break; + case SET_MEMORY_RW: + pte_update_delta(ptep, addr, _PAGE_KERNEL_RO, _PAGE_KERNEL_RW); + break; + case SET_MEMORY_NX: + pte_update_delta(ptep, addr, _PAGE_KERNEL_ROX, _PAGE_KERNEL_RO); + break; + case SET_MEMORY_X: + pte_update_delta(ptep, addr, _PAGE_KERNEL_RO, _PAGE_KERNEL_ROX); + break; + case SET_MEMORY_NP: + pte_update(&init_mm, addr, ptep, _PAGE_PRESENT, 0, 0); + break; + case SET_MEMORY_P: + pte_update(&init_mm, addr, ptep, 0, _PAGE_PRESENT, 0); + break; + default: + WARN_ON_ONCE(1); + break; + } + + /* See ptesync comment in radix__set_pte_at() */ + if (radix_enabled()) + asm volatile("ptesync": : :"memory"); + + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + + return 0; +} + +int change_memory_attr(unsigned long addr, int numpages, long action) +{ + unsigned long start = ALIGN_DOWN(addr, PAGE_SIZE); + unsigned long size = numpages * PAGE_SIZE; + + if (!numpages) + return 0; + + if (WARN_ON_ONCE(is_vmalloc_or_module_addr((void *)addr) && + is_vm_area_hugepages((void *)addr))) + return -EINVAL; + +#ifdef CONFIG_PPC_BOOK3S_64 + /* + * On hash, the linear mapping is not in the Linux page table so + * apply_to_existing_page_range() will have no effect. If in the future + * the set_memory_* functions are used on the linear map this will need + * to be updated. + */ + if (!radix_enabled()) { + int region = get_region_id(addr); + + if (WARN_ON_ONCE(region != VMALLOC_REGION_ID && region != IO_REGION_ID)) + return -EINVAL; + } +#endif + + return apply_to_existing_page_range(&init_mm, start, size, + change_page_attr, (void *)action); +} + +#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE) +#ifdef CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC +void __kernel_map_pages(struct page *page, int numpages, int enable) +{ + int err; + unsigned long addr = (unsigned long)page_address(page); + + if (PageHighMem(page)) + return; + + if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && !radix_enabled()) + err = hash__kernel_map_pages(page, numpages, enable); + else if (enable) + err = set_memory_p(addr, numpages); + else + err = set_memory_np(addr, numpages); + + if (err) + panic("%s: changing memory protections failed\n", __func__); +} +#endif +#endif -- cgit v1.3.1