From f62995c92a29e4d9331382b8b2461eef3b9c7c6b Mon Sep 17 00:00:00 2001 From: Baoquan He Date: Sun, 9 Jul 2017 20:37:39 +0800 Subject: [PATCH] x86/boot/KASLR: Wrap e820 entries walking code into new function process_e820_entries() The original function process_e820_entry() only takes care of each e820 entry passed. And move the E820_TYPE_RAM checking logic into process_e820_entries(). And remove the redundent local variable 'addr' definition in find_random_phys_addr(). Signed-off-by: Baoquan He Acked-by: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: fanc.fnst@cn.fujitsu.com Cc: izumi.taku@jp.fujitsu.com Cc: matt@codeblueprint.co.uk Cc: thgarnie@google.com Link: http://lkml.kernel.org/r/1499603862-11516-2-git-send-email-bhe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/boot/compressed/kaslr.c | 38 ++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 17 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 91f27ab970ef..1485f48aeda1 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -488,10 +488,6 @@ static void process_e820_entry(struct boot_e820_entry *entry, unsigned long start_orig, end; struct boot_e820_entry cur_entry; - /* Skip non-RAM entries. */ - if (entry->type != E820_TYPE_RAM) - return; - /* On 32-bit, ignore entries entirely above our maximum. */ if (IS_ENABLED(CONFIG_X86_32) && entry->addr >= KERNEL_IMAGE_SIZE) return; @@ -562,12 +558,29 @@ static void process_e820_entry(struct boot_e820_entry *entry, } } -static unsigned long find_random_phys_addr(unsigned long minimum, - unsigned long image_size) +static void process_e820_entries(unsigned long minimum, + unsigned long image_size) { int i; - unsigned long addr; + struct boot_e820_entry *entry; + + /* Verify potential e820 positions, appending to slots list. */ + for (i = 0; i < boot_params->e820_entries; i++) { + entry = &boot_params->e820_table[i]; + /* Skip non-RAM entries. */ + if (entry->type != E820_TYPE_RAM) + continue; + process_e820_entry(entry, minimum, image_size); + if (slot_area_index == MAX_SLOT_AREA) { + debug_putstr("Aborted e820 scan (slot_areas full)!\n"); + break; + } + } +} +static unsigned long find_random_phys_addr(unsigned long minimum, + unsigned long image_size) +{ /* Check if we had too many memmaps. */ if (memmap_too_large) { debug_putstr("Aborted e820 scan (more than 4 memmap= args)!\n"); @@ -577,16 +590,7 @@ static unsigned long find_random_phys_addr(unsigned long minimum, /* Make sure minimum is aligned. */ minimum = ALIGN(minimum, CONFIG_PHYSICAL_ALIGN); - /* Verify potential e820 positions, appending to slots list. */ - for (i = 0; i < boot_params->e820_entries; i++) { - process_e820_entry(&boot_params->e820_table[i], minimum, - image_size); - if (slot_area_index == MAX_SLOT_AREA) { - debug_putstr("Aborted e820 scan (slot_areas full)!\n"); - break; - } - } - + process_e820_entries(minimum, image_size); return slots_fetch_random(); } -- 2.20.1