// SPDX-License-Identifier: GPL-2.0-only #include <linux/coredump.h>#include <linux/elfcore.h>#include <linux/kernel.h>#include <linux/mm.h> #include <asm/cpufeature.h>#include <asm/mte.h> #define for_each_mte_vma(cprm, i, m)					\	if (system_supports_mte())					\		for (i = 0, m = cprm->vma_meta;				\		     i < cprm->vma_count;				\		     i++, m = cprm->vma_meta + i)			\			if (m->flags & VM_MTE) static unsigned long mte_vma_tag_dump_size(struct core_vma_metadata *m){	return (m->dump_size >> PAGE_SHIFT) * MTE_PAGE_TAG_STORAGE;} /* Derived from dump_user_range(); start/end must be page-aligned */static int mte_dump_tag_range(struct coredump_params *cprm,			      unsigned long start, unsigned long len){	int ret = 1;	unsigned long addr;	void *tags = NULL;	int locked = 0; 	for (addr = start; addr < start + len; addr += PAGE_SIZE) {		struct page *page = get_dump_page(addr, &locked); 		/*		 * get_dump_page() returns NULL when encountering an empty		 * page table entry that would otherwise have been filled with		 * the zero page. Skip the equivalent tag dump which would		 * have been all zeros.		 */		if (!page) {			dump_skip(cprm, MTE_PAGE_TAG_STORAGE);			continue;		} 		/*		 * Pages mapped in user space as !pte_access_permitted() (e.g.		 * PROT_EXEC only) may not have the PG_mte_tagged flag set.		 */		if (!page_mte_tagged(page)) {			put_page(page);			dump_skip(cprm, MTE_PAGE_TAG_STORAGE);			continue;		} 		if (!tags) {			tags = mte_allocate_tag_storage();			if (!tags) {				put_page(page);				ret = 0;				break;			}		} 		mte_save_page_tags(page_address(page), tags);		put_page(page);		if (!dump_emit(cprm, tags, MTE_PAGE_TAG_STORAGE)) {			ret = 0;			break;		}	} 	if (tags)		mte_free_tag_storage(tags); 	return ret;} Elf_Half elf_core_extra_phdrs(struct coredump_params *cprm){	int i;	struct core_vma_metadata *m;	int vma_count = 0; 	for_each_mte_vma(cprm, i, m)		vma_count++; 	return vma_count;} int elf_core_write_extra_phdrs(struct coredump_params *cprm, loff_t offset){	int i;	struct core_vma_metadata *m; 	for_each_mte_vma(cprm, i, m) {		struct elf_phdr phdr; 		phdr.p_type = PT_AARCH64_MEMTAG_MTE;		phdr.p_offset = offset;		phdr.p_vaddr = m->start;		phdr.p_paddr = 0;		phdr.p_filesz = mte_vma_tag_dump_size(m);		phdr.p_memsz = m->end - m->start;		offset += phdr.p_filesz;		phdr.p_flags = 0;		phdr.p_align = 0; 		if (!dump_emit(cprm, &phdr, sizeof(phdr)))			return 0;	} 	return 1;} size_t elf_core_extra_data_size(struct coredump_params *cprm){	int i;	struct core_vma_metadata *m;	size_t data_size = 0; 	for_each_mte_vma(cprm, i, m)		data_size += mte_vma_tag_dump_size(m); 	return data_size;} int elf_core_write_extra_data(struct coredump_params *cprm){	int i;	struct core_vma_metadata *m; 	for_each_mte_vma(cprm, i, m) {		if (!mte_dump_tag_range(cprm, m->start, m->dump_size))			return 0;	} 	return 1;}