mirror of
https://github.com/brain-hackers/linux-brain.git
synced 2024-06-09 23:36:23 +09:00
9e451933bb
commit 4c1cbcbd6c56c79de2c07159be4f55386bb0bef2 upstream.
With certain kernel configurations, the R_390_JMP_SLOT relocation type
might be generated, which is not expected by the KASLR relocation code,
and the kernel stops with the message "Unknown relocation type".
This was found with a zfcpdump kernel config, where CONFIG_MODULES=n
and CONFIG_VFIO=n. In that case, symbol_get() is used on undefined
__weak symbols in virt/kvm/vfio.c, which results in the generation
of R_390_JMP_SLOT relocation types.
Fix this by handling R_390_JMP_SLOT similar to R_390_GLOB_DAT.
Fixes: 805bc0bc23 ("s390/kernel: build a relocatable kernel")
Cc: <stable@vger.kernel.org> # v5.2+
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
57 lines
1.3 KiB
C
57 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/elf.h>
|
|
#include <asm/kexec.h>
|
|
|
|
int arch_kexec_do_relocs(int r_type, void *loc, unsigned long val,
|
|
unsigned long addr)
|
|
{
|
|
switch (r_type) {
|
|
case R_390_NONE:
|
|
break;
|
|
case R_390_8: /* Direct 8 bit. */
|
|
*(u8 *)loc = val;
|
|
break;
|
|
case R_390_12: /* Direct 12 bit. */
|
|
*(u16 *)loc &= 0xf000;
|
|
*(u16 *)loc |= val & 0xfff;
|
|
break;
|
|
case R_390_16: /* Direct 16 bit. */
|
|
*(u16 *)loc = val;
|
|
break;
|
|
case R_390_20: /* Direct 20 bit. */
|
|
*(u32 *)loc &= 0xf00000ff;
|
|
*(u32 *)loc |= (val & 0xfff) << 16; /* DL */
|
|
*(u32 *)loc |= (val & 0xff000) >> 4; /* DH */
|
|
break;
|
|
case R_390_32: /* Direct 32 bit. */
|
|
*(u32 *)loc = val;
|
|
break;
|
|
case R_390_64: /* Direct 64 bit. */
|
|
case R_390_GLOB_DAT:
|
|
case R_390_JMP_SLOT:
|
|
*(u64 *)loc = val;
|
|
break;
|
|
case R_390_PC16: /* PC relative 16 bit. */
|
|
*(u16 *)loc = (val - addr);
|
|
break;
|
|
case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */
|
|
*(u16 *)loc = (val - addr) >> 1;
|
|
break;
|
|
case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */
|
|
*(u32 *)loc = (val - addr) >> 1;
|
|
break;
|
|
case R_390_PC32: /* PC relative 32 bit. */
|
|
*(u32 *)loc = (val - addr);
|
|
break;
|
|
case R_390_PC64: /* PC relative 64 bit. */
|
|
*(u64 *)loc = (val - addr);
|
|
break;
|
|
case R_390_RELATIVE:
|
|
*(unsigned long *) loc = val;
|
|
break;
|
|
default:
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|