From 0eb1a8af01d6264cf948d67c8bff15e2eb859355 Mon Sep 17 00:00:00 2001 From: Arvind Sankar Date: Tue, 28 Jul 2020 18:57:21 -0400 Subject: [PATCH] x86/kaslr: Make local variables 64-bit Change the type of local variables/fields that store mem_vector addresses to u64 to make it less likely that 32-bit overflow will cause issues on 32-bit. Signed-off-by: Arvind Sankar Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200728225722.67457-21-nivedita@alum.mit.edu --- arch/x86/boot/compressed/kaslr.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index db8589c..80cdd20 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -461,7 +461,7 @@ static bool mem_avoid_overlap(struct mem_vector *img, { int i; struct setup_data *ptr; - unsigned long earliest = img->start + img->size; + u64 earliest = img->start + img->size; bool is_overlapping = false; for (i = 0; i < MEM_AVOID_MAX; i++) { @@ -506,7 +506,7 @@ static bool mem_avoid_overlap(struct mem_vector *img, } struct slot_area { - unsigned long addr; + u64 addr; unsigned long num; }; @@ -537,7 +537,8 @@ static void store_slot_info(struct mem_vector *region, unsigned long image_size) static void process_gb_huge_pages(struct mem_vector *region, unsigned long image_size) { - unsigned long pud_start, pud_end, gb_huge_pages; + u64 pud_start, pud_end; + unsigned long gb_huge_pages; struct mem_vector tmp; if (!IS_ENABLED(CONFIG_X86_64) || !max_gb_huge_pages) { @@ -579,7 +580,7 @@ process_gb_huge_pages(struct mem_vector *region, unsigned long image_size) } } -static unsigned long slots_fetch_random(void) +static u64 slots_fetch_random(void) { unsigned long slot; unsigned int i; @@ -595,7 +596,7 @@ static unsigned long slots_fetch_random(void) slot -= slot_areas[i].num; continue; } - return slot_areas[i].addr + slot * CONFIG_PHYSICAL_ALIGN; + return slot_areas[i].addr + ((u64)slot * CONFIG_PHYSICAL_ALIGN); } if (i == slot_area_index) @@ -608,7 +609,7 @@ static void __process_mem_region(struct mem_vector *entry, unsigned long image_size) { struct mem_vector region, overlap; - unsigned long region_end; + u64 region_end; /* Enforce minimum and memory limit. */ region.start = max_t(u64, entry->start, minimum); -- 2.7.4