freebsd-dev/sys/i386/include/proc.h
David Chisnall cf98bc28d3 Pass the syscall number to capsicum permission-denied signals
The syscall number is stored in the same register as the syscall return
on amd64 (and possibly other architectures) and so it is impossible to
recover in the signal handler after the call has returned.  This small
tweak delivers it in the `si_value` field of the signal, which is
sufficient to catch capability violations and emulate them with a call
to a more-privileged process in the signal handler.

This reapplies 3a522ba1bc with a fix for
the static assertion failure on i386.

Approved by:	markj (mentor)

Reviewed by:	kib, bcr (manpages)

Differential Revision: https://reviews.freebsd.org/D29185
2021-07-16 18:06:44 +01:00

92 lines
2.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1991 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.
*
* from: @(#)proc.h 7.1 (Berkeley) 5/15/91
* $FreeBSD$
*/
#ifndef _MACHINE_PROC_H_
#define _MACHINE_PROC_H_
#include <machine/segments.h>
struct proc_ldt {
caddr_t ldt_base;
int ldt_len;
int ldt_refcnt;
u_long ldt_active;
struct segment_descriptor ldt_sd;
};
/*
* Machine-dependent part of the proc structure for i386.
* Table of MD locks:
* t - Descriptor tables lock
*/
struct mdthread {
int md_spinlock_count; /* (k) */
register_t md_saved_flags; /* (k) */
register_t md_spurflt_addr; /* (k) Spurious page fault address. */
};
struct mdproc {
struct proc_ldt *md_ldt; /* (t) per-process ldt */
};
#define KINFO_PROC_SIZE 768
struct syscall_args {
u_int code;
u_int original_code;
struct sysent *callp;
register_t args[8];
};
#ifdef _KERNEL
/* Get the current kernel thread stack usage. */
#define GET_STACK_USAGE(total, used) do { \
struct thread *td = curthread; \
(total) = td->td_kstack_pages * PAGE_SIZE; \
(used) = (char *)td->td_kstack + \
td->td_kstack_pages * PAGE_SIZE - \
(char *)&td; \
} while (0)
void set_user_ldt(struct mdproc *);
struct proc_ldt *user_ldt_alloc(struct mdproc *, int);
void user_ldt_free(struct thread *);
void user_ldt_deref(struct proc_ldt *pldt);
extern struct mtx dt_lock;
#endif /* _KERNEL */
#endif /* !_MACHINE_PROC_H_ */