From 16decce22efa0813beafbc9084181e299b69a1a1 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 1 Apr 2022 16:13:56 +0100 Subject: 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: Catalin Marinas Fixes: 6dd8b1a0b6cb ("arm64: mte: Dump the MTE tags in the core file") Reported-by: kernel test robot Cc: Will Deacon Link: https://lore.kernel.org/r/20220401151356.1674232-1-catalin.marinas@arm.com Signed-off-by: Will Deacon --- arch/arm64/kernel/elfcore.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/elfcore.c b/arch/arm64/kernel/elfcore.c index 3455ee4acc04..2b3f3d0544b9 100644 --- a/arch/arm64/kernel/elfcore.c +++ b/arch/arm64/kernel/elfcore.c @@ -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) -- cgit v1.2.3