From 73b9160d0dfe44dfdaffd6465dc1224c38a4a73c Mon Sep 17 00:00:00 2001 From: Jinbum Park Date: Tue, 6 Mar 2018 01:37:21 +0100 Subject: [PATCH] ARM: 8748/1: mm: Define vdso_start, vdso_end as array Define vdso_start, vdso_end as array to avoid compile-time analysis error for the case of built with CONFIG_FORTIFY_SOURCE. and, since vdso_start, vdso_end are used in vdso.c only, move extern-declaration from vdso.h to vdso.c. If kernel is built with CONFIG_FORTIFY_SOURCE, compile-time error happens at this code. - if (memcmp(&vdso_start, "177ELF", 4)) The size of "&vdso_start" is recognized as 1 byte, but n is 4, So that compile-time error is reported. Acked-by: Kees Cook Signed-off-by: Jinbum Park Signed-off-by: Russell King --- arch/arm/include/asm/vdso.h | 2 -- arch/arm/kernel/vdso.c | 12 +++++++----- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/arm/include/asm/vdso.h b/arch/arm/include/asm/vdso.h index 9c99e817535e..5b85889f82ee 100644 --- a/arch/arm/include/asm/vdso.h +++ b/arch/arm/include/asm/vdso.h @@ -12,8 +12,6 @@ struct mm_struct; void arm_install_vdso(struct mm_struct *mm, unsigned long addr); -extern char vdso_start, vdso_end; - extern unsigned int vdso_total_pages; #else /* CONFIG_VDSO */ diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c index a4d6dc0f2427..f4dd7f9663c1 100644 --- a/arch/arm/kernel/vdso.c +++ b/arch/arm/kernel/vdso.c @@ -39,6 +39,8 @@ static struct page **vdso_text_pagelist; +extern char vdso_start[], vdso_end[]; + /* Total number of pages needed for the data and text portions of the VDSO. */ unsigned int vdso_total_pages __ro_after_init; @@ -197,13 +199,13 @@ static int __init vdso_init(void) unsigned int text_pages; int i; - if (memcmp(&vdso_start, "\177ELF", 4)) { + if (memcmp(vdso_start, "\177ELF", 4)) { pr_err("VDSO is not a valid ELF object!\n"); return -ENOEXEC; } - text_pages = (&vdso_end - &vdso_start) >> PAGE_SHIFT; - pr_debug("vdso: %i text pages at base %p\n", text_pages, &vdso_start); + text_pages = (vdso_end - vdso_start) >> PAGE_SHIFT; + pr_debug("vdso: %i text pages at base %p\n", text_pages, vdso_start); /* Allocate the VDSO text pagelist */ vdso_text_pagelist = kcalloc(text_pages, sizeof(struct page *), @@ -218,7 +220,7 @@ static int __init vdso_init(void) for (i = 0; i < text_pages; i++) { struct page *page; - page = virt_to_page(&vdso_start + i * PAGE_SIZE); + page = virt_to_page(vdso_start + i * PAGE_SIZE); vdso_text_pagelist[i] = page; } @@ -229,7 +231,7 @@ static int __init vdso_init(void) cntvct_ok = cntvct_functional(); - patch_vdso(&vdso_start); + patch_vdso(vdso_start); return 0; }