freebsd-nq/sys/sys/sysent.h
Konstantin Belousov 1c69690319 Unmap shared page manually before doing vm_map_remove() on exit or exec
This allows the pmap_remove(min, max) call to see empty pmap and exploit
empty pmap optimization.

Reviewed by:	markj
Tested by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D32569
2021-10-28 22:01:59 +03:00

337 lines
12 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1982, 1988, 1991 The Regents of the University of California.
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* $FreeBSD$
*/
#ifndef _SYS_SYSENT_H_
#define _SYS_SYSENT_H_
#include <bsm/audit.h>
struct rlimit;
struct sysent;
struct thread;
struct ksiginfo;
struct syscall_args;
enum systrace_probe_t {
SYSTRACE_ENTRY,
SYSTRACE_RETURN,
};
typedef int sy_call_t(struct thread *, void *);
typedef void (*systrace_probe_func_t)(struct syscall_args *,
enum systrace_probe_t, int);
typedef void (*systrace_args_func_t)(int, void *, uint64_t *, int *);
#ifdef _KERNEL
extern systrace_probe_func_t systrace_probe_func;
extern bool systrace_enabled;
#ifdef KDTRACE_HOOKS
#define SYSTRACE_ENABLED() (systrace_enabled)
#else
#define SYSTRACE_ENABLED() (0)
#endif
#endif /* _KERNEL */
struct sysent { /* system call table */
sy_call_t *sy_call; /* implementing function */
systrace_args_func_t sy_systrace_args_func;
/* optional argument conversion function. */
u_int8_t sy_narg; /* number of arguments */
u_int8_t sy_flags; /* General flags for system calls. */
au_event_t sy_auevent; /* audit event associated with syscall */
u_int32_t sy_entry; /* DTrace entry ID for systrace. */
u_int32_t sy_return; /* DTrace return ID for systrace. */
u_int32_t sy_thrcnt;
};
/*
* A system call is permitted in capability mode.
*/
#define SYF_CAPENABLED 0x00000001
#define SY_THR_FLAGMASK 0x7
#define SY_THR_STATIC 0x1
#define SY_THR_DRAINING 0x2
#define SY_THR_ABSENT 0x4
#define SY_THR_INCR 0x8
#ifdef KLD_MODULE
#define SY_THR_STATIC_KLD 0
#else
#define SY_THR_STATIC_KLD SY_THR_STATIC
#endif
struct image_params;
struct proc;
struct __sigset;
struct trapframe;
struct vnode;
struct note_info_list;
struct sysentvec {
int sv_size; /* number of entries */
struct sysent *sv_table; /* pointer to sysent */
int (*sv_transtrap)(int, int);
/* translate trap-to-signal mapping */
int (*sv_fixup)(uintptr_t *, struct image_params *);
/* stack fixup function */
void (*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *);
/* send signal */
char *sv_sigcode; /* start of sigtramp code */
int *sv_szsigcode; /* size of sigtramp code */
char *sv_name; /* name of binary type */
int (*sv_coredump)(struct thread *, struct vnode *, off_t, int);
/* function to dump core, or NULL */
int sv_elf_core_osabi;
const char *sv_elf_core_abi_vendor;
void (*sv_elf_core_prepare_notes)(struct thread *,
struct note_info_list *, size_t *);
int (*sv_imgact_try)(struct image_params *);
vm_size_t (*sv_stackgap)(struct image_params *, uintptr_t *);
int (*sv_copyout_auxargs)(struct image_params *,
uintptr_t);
int sv_minsigstksz; /* minimum signal stack size */
vm_offset_t sv_minuser; /* VM_MIN_ADDRESS */
vm_offset_t sv_maxuser; /* VM_MAXUSER_ADDRESS */
vm_offset_t sv_usrstack; /* USRSTACK */
vm_offset_t sv_psstrings; /* PS_STRINGS */
int sv_stackprot; /* vm protection for stack */
int (*sv_copyout_strings)(struct image_params *,
uintptr_t *);
void (*sv_setregs)(struct thread *, struct image_params *,
uintptr_t);
void (*sv_fixlimit)(struct rlimit *, int);
u_long *sv_maxssiz;
u_int sv_flags;
void (*sv_set_syscall_retval)(struct thread *, int);
int (*sv_fetch_syscall_args)(struct thread *);
const char **sv_syscallnames;
vm_offset_t sv_timekeep_base;
vm_offset_t sv_shared_page_base;
vm_offset_t sv_shared_page_len;
vm_offset_t sv_sigcode_base;
void *sv_shared_page_obj;
void (*sv_schedtail)(struct thread *);
void (*sv_thread_detach)(struct thread *);
int (*sv_trap)(struct thread *);
u_long *sv_hwcap; /* Value passed in AT_HWCAP. */
u_long *sv_hwcap2; /* Value passed in AT_HWCAP2. */
const char *(*sv_machine_arch)(struct proc *);
vm_offset_t sv_fxrng_gen_base;
void (*sv_onexec_old)(struct thread *td);
int (*sv_onexec)(struct proc *, struct image_params *);
void (*sv_onexit)(struct proc *);
void (*sv_ontdexit)(struct thread *td);
int (*sv_setid_allowed)(struct thread *td,
struct image_params *imgp);
void (*sv_set_fork_retval)(struct thread *);
/* Only used on x86 */
};
#define SV_ILP32 0x000100 /* 32-bit executable. */
#define SV_LP64 0x000200 /* 64-bit executable. */
#define SV_IA32 0x004000 /* Intel 32-bit executable. */
#define SV_AOUT 0x008000 /* a.out executable. */
#define SV_SHP 0x010000 /* Shared page. */
#define SV_AVAIL1 0x020000 /* Unused */
#define SV_TIMEKEEP 0x040000 /* Shared page timehands. */
#define SV_ASLR 0x080000 /* ASLR allowed. */
#define SV_RNG_SEED_VER 0x100000 /* random(4) reseed generation. */
#define SV_SIG_DISCIGN 0x200000 /* Do not discard ignored signals */
#define SV_SIG_WAITNDQ 0x400000 /* Wait does not dequeue SIGCHLD */
#define SV_ABI_MASK 0xff
#define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x))
#define SV_PROC_ABI(p) ((p)->p_sysent->sv_flags & SV_ABI_MASK)
#define SV_CURPROC_FLAG(x) SV_PROC_FLAG(curproc, x)
#define SV_CURPROC_ABI() SV_PROC_ABI(curproc)
/* same as ELFOSABI_XXX, to prevent header pollution */
#define SV_ABI_LINUX 3
#define SV_ABI_FREEBSD 9
#define SV_ABI_UNDEF 255
/* sv_coredump flags */
#define SVC_PT_COREDUMP 0x00000001 /* dump requested by ptrace(2) */
#define SVC_NOCOMPRESS 0x00000002 /* disable compression. */
#define SVC_ALL 0x00000004 /* dump everything */
#ifdef _KERNEL
extern struct sysentvec aout_sysvec;
extern struct sysent sysent[];
extern const char *syscallnames[];
#define NO_SYSCALL (-1)
struct module;
struct syscall_module_data {
int (*chainevh)(struct module *, int, void *); /* next handler */
void *chainarg; /* arg for next event handler */
int *offset; /* offset into sysent */
struct sysent *new_sysent; /* new sysent */
struct sysent old_sysent; /* old sysent */
int flags; /* flags for syscall_register */
};
/* separate initialization vector so it can be used in a substructure */
#define SYSENT_INIT_VALS(_syscallname) { \
.sy_narg = (sizeof(struct _syscallname ## _args ) \
/ sizeof(register_t)), \
.sy_call = (sy_call_t *)&sys_##_syscallname, \
.sy_auevent = SYS_AUE_##_syscallname, \
.sy_systrace_args_func = NULL, \
.sy_entry = 0, \
.sy_return = 0, \
.sy_flags = 0, \
.sy_thrcnt = 0 \
}
#define MAKE_SYSENT(syscallname) \
static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname);
#define MAKE_SYSENT_COMPAT(syscallname) \
static struct sysent syscallname##_sysent = { \
(sizeof(struct syscallname ## _args ) \
/ sizeof(register_t)), \
(sy_call_t *)& syscallname, \
SYS_AUE_##syscallname \
}
#define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \
static struct syscall_module_data name##_syscall_mod = { \
evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \
}; \
\
static moduledata_t name##_mod = { \
"sys/" #name, \
syscall_module_handler, \
&name##_syscall_mod \
}; \
DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE)
#define SYSCALL_MODULE_HELPER(syscallname) \
static int syscallname##_syscall = SYS_##syscallname; \
MAKE_SYSENT(syscallname); \
SYSCALL_MODULE(syscallname, \
& syscallname##_syscall, & syscallname##_sysent, \
NULL, NULL)
#define SYSCALL_MODULE_PRESENT(syscallname) \
(sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \
sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys)
/*
* Syscall registration helpers with resource allocation handling.
*/
struct syscall_helper_data {
struct sysent new_sysent;
struct sysent old_sysent;
int syscall_no;
int registered;
};
#define SYSCALL_INIT_HELPER_F(syscallname, flags) { \
.new_sysent = { \
.sy_narg = (sizeof(struct syscallname ## _args ) \
/ sizeof(register_t)), \
.sy_call = (sy_call_t *)& sys_ ## syscallname, \
.sy_auevent = SYS_AUE_##syscallname, \
.sy_flags = (flags) \
}, \
.syscall_no = SYS_##syscallname \
}
#define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \
.new_sysent = { \
.sy_narg = (sizeof(struct syscallname ## _args ) \
/ sizeof(register_t)), \
.sy_call = (sy_call_t *)& syscallname, \
.sy_auevent = SYS_AUE_##syscallname, \
.sy_flags = (flags) \
}, \
.syscall_no = SYS_##syscallname \
}
#define SYSCALL_INIT_HELPER(syscallname) \
SYSCALL_INIT_HELPER_F(syscallname, 0)
#define SYSCALL_INIT_HELPER_COMPAT(syscallname) \
SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0)
#define SYSCALL_INIT_LAST { \
.syscall_no = NO_SYSCALL \
}
int syscall_module_handler(struct module *mod, int what, void *arg);
int syscall_helper_register(struct syscall_helper_data *sd, int flags);
int syscall_helper_unregister(struct syscall_helper_data *sd);
/* Implementation, exposed for COMPAT code */
int kern_syscall_register(struct sysent *sysents, int *offset,
struct sysent *new_sysent, struct sysent *old_sysent, int flags);
int kern_syscall_deregister(struct sysent *sysents, int offset,
const struct sysent *old_sysent);
int kern_syscall_module_handler(struct sysent *sysents,
struct module *mod, int what, void *arg);
int kern_syscall_helper_register(struct sysent *sysents,
struct syscall_helper_data *sd, int flags);
int kern_syscall_helper_unregister(struct sysent *sysents,
struct syscall_helper_data *sd);
struct proc;
const char *syscallname(struct proc *p, u_int code);
/* Special purpose system call functions. */
struct nosys_args;
int lkmnosys(struct thread *, struct nosys_args *);
int lkmressys(struct thread *, struct nosys_args *);
int syscall_thread_enter(struct thread *td, struct sysent *se);
void syscall_thread_exit(struct thread *td, struct sysent *se);
int shared_page_alloc(int size, int align);
int shared_page_fill(int size, int align, const void *data);
void shared_page_write(int base, int size, const void *data);
void exec_sysvec_init(void *param);
void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2);
void exec_inittk(void);
void exit_onexit(struct proc *p);
void exec_free_abi_mappings(struct proc *p);
void exec_onexec_old(struct thread *td);
#define INIT_SYSENTVEC(name, sv) \
SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \
(sysinit_cfunc_t)exec_sysvec_init, sv);
#endif /* _KERNEL */
#endif /* !_SYS_SYSENT_H_ */