linux_dsm_epyc7002/arch/powerpc/include/asm/sections.h
Naveen N. Rao 7aa5b018bf powerpc/kprobes: Blacklist exception handlers
Introduce __head_end to mark end of the early fixed sections and use it to
blacklist all exception handlers from kprobes.

mpe: We do not need to do anything special for relocatable kernels, where the
exception vectors are split from the main kernel, as the split vectors are
already excluded by the check for kernel_text_address().

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Move __head_end outside #ifdef 64-bit to unbreak the 32-bit build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-23 20:32:25 +10:00

84 lines
1.9 KiB
C

#ifndef _ASM_POWERPC_SECTIONS_H
#define _ASM_POWERPC_SECTIONS_H
#ifdef __KERNEL__
#include <linux/elf.h>
#include <linux/uaccess.h>
#include <asm-generic/sections.h>
extern char __head_end[];
#ifdef __powerpc64__
extern char __start_interrupts[];
extern char __end_interrupts[];
extern char __prom_init_toc_start[];
extern char __prom_init_toc_end[];
static inline int in_kernel_text(unsigned long addr)
{
if (addr >= (unsigned long)_stext && addr < (unsigned long)__init_end)
return 1;
return 0;
}
static inline unsigned long kernel_toc_addr(void)
{
/* Defined by the linker, see vmlinux.lds.S */
extern unsigned long __toc_start;
/*
* The TOC register (r2) points 32kB into the TOC, so that 64kB of
* the TOC can be addressed using a single machine instruction.
*/
return (unsigned long)(&__toc_start) + 0x8000UL;
}
static inline int overlaps_interrupt_vector_text(unsigned long start,
unsigned long end)
{
unsigned long real_start, real_end;
real_start = __start_interrupts - _stext;
real_end = __end_interrupts - _stext;
return start < (unsigned long)__va(real_end) &&
(unsigned long)__va(real_start) < end;
}
static inline int overlaps_kernel_text(unsigned long start, unsigned long end)
{
return start < (unsigned long)__init_end &&
(unsigned long)_stext < end;
}
static inline int overlaps_kvm_tmp(unsigned long start, unsigned long end)
{
#ifdef CONFIG_KVM_GUEST
extern char kvm_tmp[];
return start < (unsigned long)kvm_tmp &&
(unsigned long)&kvm_tmp[1024 * 1024] < end;
#else
return 0;
#endif
}
#ifdef PPC64_ELF_ABI_v1
#undef dereference_function_descriptor
static inline void *dereference_function_descriptor(void *ptr)
{
struct ppc64_opd_entry *desc = ptr;
void *p;
if (!probe_kernel_address(&desc->funcaddr, p))
ptr = p;
return ptr;
}
#endif /* PPC64_ELF_ABI_v1 */
#endif
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_SECTIONS_H */