freebsd-dev/sys/compat/ia32/ia32_sysvec.c
Andrew Turner 548a2ec49b Add PT_GETREGSET
This adds the PT_GETREGSET and PT_SETREGSET ptrace types. These can be
used to access all the registers from a specified core dump note type.
The NT_PRSTATUS and NT_FPREGSET notes are initially supported. Other
machine-dependant types are expected to be added in the future.

The ptrace addr points to a struct iovec pointing at memory to hold the
registers along with its length. On success the length in the iovec is
updated to tell userspace the actual length the kernel wrote or, if the
base address is NULL, the length the kernel would have written.

Because the data field is an int the arguments are backwards when
compared to the Linux PTRACE_GETREGSET call.

Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D19831
2022-01-27 11:40:34 +00:00

251 lines
7.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2002 Doug Rabson
* Copyright (c) 2003 Peter Wemm
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#define __ELF_WORD_SIZE 32
#include <sys/param.h>
#include <sys/elf.h>
#include <sys/exec.h>
#include <sys/fcntl.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/mman.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/procfs.h>
#include <sys/reg.h>
#include <sys/resourcevar.h>
#include <sys/systm.h>
#include <sys/signalvar.h>
#include <sys/stat.h>
#include <sys/sx.h>
#include <sys/syscall.h>
#include <sys/sysctl.h>
#include <sys/sysent.h>
#include <sys/vnode.h>
#include <sys/imgact_elf.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <compat/freebsd32/freebsd32_signal.h>
#include <compat/freebsd32/freebsd32_util.h>
#include <compat/freebsd32/freebsd32_proto.h>
#include <compat/freebsd32/freebsd32_syscall.h>
#include <compat/ia32/ia32_signal.h>
#include <machine/frame.h>
#include <machine/md_var.h>
#include <machine/pcb.h>
#include <machine/cpufunc.h>
CTASSERT(sizeof(struct ia32_mcontext) == 640);
CTASSERT(sizeof(struct ia32_ucontext) == 704);
CTASSERT(sizeof(struct ia32_sigframe) == 800);
CTASSERT(sizeof(struct siginfo32) == 64);
#ifdef COMPAT_FREEBSD4
CTASSERT(sizeof(struct ia32_freebsd4_mcontext) == 260);
CTASSERT(sizeof(struct ia32_freebsd4_ucontext) == 324);
CTASSERT(sizeof(struct ia32_freebsd4_sigframe) == 408);
#endif
#include "vdso_ia32_offsets.h"
extern const char _binary_elf_vdso32_so_1_start[];
extern const char _binary_elf_vdso32_so_1_end[];
extern char _binary_elf_vdso32_so_1_size;
extern const char *freebsd32_syscallnames[];
static SYSCTL_NODE(_compat, OID_AUTO, ia32, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"ia32 mode");
static u_long ia32_maxdsiz = IA32_MAXDSIZ;
SYSCTL_ULONG(_compat_ia32, OID_AUTO, maxdsiz, CTLFLAG_RWTUN, &ia32_maxdsiz, 0, "");
u_long ia32_maxssiz = IA32_MAXSSIZ;
SYSCTL_ULONG(_compat_ia32, OID_AUTO, maxssiz, CTLFLAG_RWTUN, &ia32_maxssiz, 0, "");
static u_long ia32_maxvmem = IA32_MAXVMEM;
SYSCTL_ULONG(_compat_ia32, OID_AUTO, maxvmem, CTLFLAG_RWTUN, &ia32_maxvmem, 0, "");
struct sysentvec ia32_freebsd_sysvec = {
.sv_size = FREEBSD32_SYS_MAXSYSCALL,
.sv_table = freebsd32_sysent,
.sv_transtrap = NULL,
.sv_fixup = elf32_freebsd_fixup,
.sv_sendsig = ia32_sendsig,
.sv_sigcode = _binary_elf_vdso32_so_1_start,
.sv_szsigcode = (int *)&_binary_elf_vdso32_so_1_size,
.sv_sigcodeoff = VDSO_IA32_SIGCODE_OFFSET,
.sv_name = "FreeBSD ELF32",
.sv_coredump = elf32_coredump,
.sv_elf_core_osabi = ELFOSABI_FREEBSD,
.sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR,
.sv_elf_core_prepare_notes = elf32_prepare_notes,
.sv_imgact_try = NULL,
.sv_minsigstksz = MINSIGSTKSZ,
.sv_minuser = FREEBSD32_MINUSER,
.sv_maxuser = FREEBSD32_MAXUSER,
.sv_usrstack = FREEBSD32_USRSTACK,
.sv_psstrings = FREEBSD32_PS_STRINGS,
.sv_psstringssz = sizeof(struct freebsd32_ps_strings),
.sv_stackprot = VM_PROT_ALL,
.sv_copyout_auxargs = elf32_freebsd_copyout_auxargs,
.sv_copyout_strings = freebsd32_copyout_strings,
.sv_setregs = ia32_setregs,
.sv_fixlimit = ia32_fixlimit,
.sv_maxssiz = &ia32_maxssiz,
.sv_flags = SV_ABI_FREEBSD | SV_ASLR | SV_IA32 | SV_ILP32 |
SV_SHP | SV_TIMEKEEP | SV_RNG_SEED_VER | SV_DSO_SIG,
.sv_set_syscall_retval = ia32_set_syscall_retval,
.sv_fetch_syscall_args = ia32_fetch_syscall_args,
.sv_syscallnames = freebsd32_syscallnames,
.sv_shared_page_base = FREEBSD32_SHAREDPAGE,
.sv_shared_page_len = PAGE_SIZE,
.sv_schedtail = NULL,
.sv_thread_detach = NULL,
.sv_trap = NULL,
.sv_onexec_old = exec_onexec_old,
.sv_onexit = exit_onexit,
.sv_set_fork_retval = x86_set_fork_retval,
.sv_regset_begin = SET_BEGIN(__elfN(regset)),
.sv_regset_end = SET_LIMIT(__elfN(regset)),
};
INIT_SYSENTVEC(elf_ia32_sysvec, &ia32_freebsd_sysvec);
static Elf32_Brandinfo ia32_brand_info = {
.brand = ELFOSABI_FREEBSD,
.machine = EM_386,
.compat_3_brand = "FreeBSD",
.emul_path = NULL,
.interp_path = "/libexec/ld-elf.so.1",
.sysvec = &ia32_freebsd_sysvec,
.interp_newpath = "/libexec/ld-elf32.so.1",
.brand_note = &elf32_freebsd_brandnote,
.flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
};
SYSINIT(ia32, SI_SUB_EXEC, SI_ORDER_MIDDLE,
(sysinit_cfunc_t) elf32_insert_brand_entry,
&ia32_brand_info);
static Elf32_Brandinfo ia32_brand_oinfo = {
.brand = ELFOSABI_FREEBSD,
.machine = EM_386,
.compat_3_brand = "FreeBSD",
.emul_path = NULL,
.interp_path = "/usr/libexec/ld-elf.so.1",
.sysvec = &ia32_freebsd_sysvec,
.interp_newpath = "/libexec/ld-elf32.so.1",
.brand_note = &elf32_freebsd_brandnote,
.flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
};
SYSINIT(oia32, SI_SUB_EXEC, SI_ORDER_ANY,
(sysinit_cfunc_t) elf32_insert_brand_entry,
&ia32_brand_oinfo);
static Elf32_Brandinfo kia32_brand_info = {
.brand = ELFOSABI_FREEBSD,
.machine = EM_386,
.compat_3_brand = "FreeBSD",
.emul_path = NULL,
.interp_path = "/lib/ld.so.1",
.sysvec = &ia32_freebsd_sysvec,
.brand_note = &elf32_kfreebsd_brandnote,
.flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY
};
SYSINIT(kia32, SI_SUB_EXEC, SI_ORDER_ANY,
(sysinit_cfunc_t) elf32_insert_brand_entry,
&kia32_brand_info);
void
elf32_dump_thread(struct thread *td, void *dst, size_t *off)
{
void *buf;
size_t len;
len = 0;
if (use_xsave) {
if (dst != NULL) {
fpugetregs(td);
len += elf32_populate_note(NT_X86_XSTATE,
get_pcb_user_save_td(td), dst,
cpu_max_ext_state_size, &buf);
*(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) =
xsave_mask;
} else
len += elf32_populate_note(NT_X86_XSTATE, NULL, NULL,
cpu_max_ext_state_size, NULL);
}
*off = len;
}
void
ia32_fixlimit(struct rlimit *rl, int which)
{
switch (which) {
case RLIMIT_DATA:
if (ia32_maxdsiz != 0) {
if (rl->rlim_cur > ia32_maxdsiz)
rl->rlim_cur = ia32_maxdsiz;
if (rl->rlim_max > ia32_maxdsiz)
rl->rlim_max = ia32_maxdsiz;
}
break;
case RLIMIT_STACK:
if (ia32_maxssiz != 0) {
if (rl->rlim_cur > ia32_maxssiz)
rl->rlim_cur = ia32_maxssiz;
if (rl->rlim_max > ia32_maxssiz)
rl->rlim_max = ia32_maxssiz;
}
break;
case RLIMIT_VMEM:
if (ia32_maxvmem != 0) {
if (rl->rlim_cur > ia32_maxvmem)
rl->rlim_cur = ia32_maxvmem;
if (rl->rlim_max > ia32_maxvmem)
rl->rlim_max = ia32_maxvmem;
}
break;
}
}