Commit 16decce2 authored by Catalin Marinas's avatar Catalin Marinas Committed by Will Deacon
Browse files

arm64: mte: Fix the stack frame size warning in mte_dump_tag_range() 



With 64K page configurations, the tags array stored on the stack of the
mte_dump_tag_range() function is 2048 bytes, triggering a compiler
warning when CONFIG_FRAME_WARN is enabled. Switch to a kmalloc()
allocation via mte_allocate_tag_storage().

Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Fixes: 6dd8b1a0 ("arm64: mte: Dump the MTE tags in the core file")
Reported-by: default avatarkernel test robot <lkp@intel.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220401151356.1674232-1-catalin.marinas@arm.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent a0ab7e5b

arch/arm64/kernel/elfcore.c

+20 −4
Original line number Diff line number Diff line
@@ -25,10 +25,11 @@ static unsigned long mte_vma_tag_dump_size(struct vm_area_struct *vma) 
static int mte_dump_tag_range(struct coredump_params *cprm,

			      unsigned long start, unsigned long end)

{

	int ret = 1;

	unsigned long addr;

	void *tags = NULL;



	for (addr = start; addr < end; addr += PAGE_SIZE) {

		char tags[MTE_PAGE_TAG_STORAGE];

		struct page *page = get_dump_page(addr);



		/*
@@ -52,13 +53,28 @@ static int mte_dump_tag_range(struct coredump_params *cprm, 
			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))

			return 0;

		if (!dump_emit(cprm, tags, MTE_PAGE_TAG_STORAGE)) {

			mte_free_tag_storage(tags);

			ret = 0;

			break;

		}

	}



	return 1;

	if (tags)

		mte_free_tag_storage(tags);



	return ret;

}



Elf_Half elf_core_extra_phdrs(void)