From 7f00eb30febf1054c74b163ced984afcdbf6e670 Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Sat, 8 Feb 2014 12:31:15 +0100 Subject: s390x/ipl: Fix crash of ELF images with arbitrary entry points When loading S390 kernels, the current code expects an ELF file with the start address 0x10000. Other ELF files cause a segmentation fault. To avoid these crashes, we should get the start address from the ELF file instead of always using a hard-coded address. Signed-off-by: Thomas Huth Acked-by: Cornelia Huck Signed-off-by: Christian Borntraeger --- hw/s390x/ipl.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'hw/s390x') diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c index 1a6397b88e..04fb1a8e05 100644 --- a/hw/s390x/ipl.c +++ b/hw/s390x/ipl.c @@ -95,7 +95,8 @@ static int s390_ipl_init(SysBusDevice *dev) } return 0; } else { - kernel_size = load_elf(ipl->kernel, NULL, NULL, NULL, NULL, + uint64_t pentry = KERN_IMAGE_START; + kernel_size = load_elf(ipl->kernel, NULL, NULL, &pentry, NULL, NULL, 1, ELF_MACHINE, 0); if (kernel_size == -1) { kernel_size = load_image_targphys(ipl->kernel, 0, ram_size); @@ -104,15 +105,19 @@ static int s390_ipl_init(SysBusDevice *dev) fprintf(stderr, "could not load kernel '%s'\n", ipl->kernel); return -1; } - /* we have to overwrite values in the kernel image, which are "rom" */ - strcpy(rom_ptr(KERN_PARM_AREA), ipl->cmdline); - /* - * we can not rely on the ELF entry point, since up to 3.2 this - * value was 0x800 (the SALIPL loader) and it wont work. For - * all (Linux) cases 0x10000 (KERN_IMAGE_START) should be fine. + * Is it a Linux kernel (starting at 0x10000)? If yes, we fill in the + * kernel parameters here as well. Note: For old kernels (up to 3.2) + * we can not rely on the ELF entry point - it was 0x800 (the SALIPL + * loader) and it won't work. For this case we force it to 0x10000, too. */ - ipl->start_addr = KERN_IMAGE_START; + if (pentry == KERN_IMAGE_START || pentry == 0x800) { + ipl->start_addr = KERN_IMAGE_START; + /* Overwrite parameters in the kernel image, which are "rom" */ + strcpy(rom_ptr(KERN_PARM_AREA), ipl->cmdline); + } else { + ipl->start_addr = pentry; + } } if (ipl->initrd) { ram_addr_t initrd_offset; -- cgit v1.2.1