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 <thuth@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
Thomas Huth 2014-02-08 12:31:15 +01:00 committed by Christian Borntraeger
parent 1eecf41b3e
commit 7f00eb30fe

View file

@ -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;