From 852dc64d665f89d8b54dd9aa7e36c3ff12bef775 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 16 May 2019 15:47:31 +0100 Subject: [PATCH] hw/arm/boot: Diagnose layouts that put initrd or DTB off the end of RAM MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We calculate the locations in memory where we want to put the initrd and the DTB based on the size of the kernel, since they come after it. Add some explicit checks that these aren't off the end of RAM entirely. (At the moment the way we calculate the initrd_start means that it can't ever be off the end of RAM, but that will change with the next commit.) Signed-off-by: Peter Maydell Reviewed-by: Alex Bennée Tested-by: Mark Rutland Message-id: 20190516144733.32399-3-peter.maydell@linaro.org --- hw/arm/boot.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/hw/arm/boot.c b/hw/arm/boot.c index bb37a9383f..5ddba727d4 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -1056,11 +1056,25 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, error_report("could not load kernel '%s'", info->kernel_filename); exit(1); } + + if (kernel_size > info->ram_size) { + error_report("kernel '%s' is too large to fit in RAM " + "(kernel size %d, RAM size %" PRId64 ")", + info->kernel_filename, kernel_size, info->ram_size); + exit(1); + } + info->entry = entry; if (is_linux) { uint32_t fixupcontext[FIXUP_MAX]; if (info->initrd_filename) { + + if (info->initrd_start >= ram_end) { + error_report("not enough space after kernel to load initrd"); + exit(1); + } + initrd_size = load_ramdisk_as(info->initrd_filename, info->initrd_start, ram_end - info->initrd_start, as); @@ -1076,6 +1090,11 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, info->initrd_filename); exit(1); } + if (info->initrd_start + initrd_size > info->ram_size) { + error_report("could not load initrd '%s': " + "too big to fit into RAM after the kernel", + info->initrd_filename); + } } else { initrd_size = 0; } @@ -1111,6 +1130,10 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, /* Place the DTB after the initrd in memory with alignment. */ info->dtb_start = QEMU_ALIGN_UP(info->initrd_start + initrd_size, align); + if (info->dtb_start >= ram_end) { + error_report("Not enough space for DTB after kernel/initrd"); + exit(1); + } fixupcontext[FIXUP_ARGPTR_LO] = info->dtb_start; fixupcontext[FIXUP_ARGPTR_HI] = info->dtb_start >> 32; } else {