214 lines
6.3 KiB
C
214 lines
6.3 KiB
C
|
/*-
|
||
|
|
* Copyright (C) 1994, David Greenman
|
||
|
|
* Copyright (c) 1990, 1993
|
||
|
|
* The Regents of the University of California. All rights reserved.
|
||
|
|
* Copyright (C) 2010 Konstantin Belousov <kib@freebsd.org>
|
||
|
|
*
|
||
|
|
* This code is derived from software contributed to Berkeley by
|
||
|
|
* the University of Utah, and William Jolitz.
|
||
|
|
*
|
||
|
|
* 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. All advertising materials mentioning features or use of this software
|
||
|
|
* must display the following acknowledgement:
|
||
|
|
* This product includes software developed by the University of
|
||
|
|
* California, Berkeley and its contributors.
|
||
|
|
* 4. 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: @(#)trap.c 7.4 (Berkeley) 5/13/91
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "opt_capsicum.h"
|
||
|
|
#include "opt_ktrace.h"
|
||
|
|
#include "opt_kdtrace.h"
|
||
|
|
|
||
|
|
__FBSDID("$FreeBSD$");
|
||
|
|
|
||
|
|
#include <sys/capability.h>
|
||
|
|
#include <sys/ktr.h>
|
||
|
|
#ifdef KTRACE
|
||
|
|
#include <sys/uio.h>
|
||
|
|
#include <sys/ktrace.h>
|
||
|
|
#endif
|
||
|
|
#include <security/audit/audit.h>
|
||
|
|
|
||
|
|
static inline int
|
||
|
|
syscallenter(struct thread *td, struct syscall_args *sa)
|
||
|
|
{
|
||
|
|
struct proc *p;
|
||
|
|
int error, traced;
|
||
|
|
|
||
|
|
PCPU_INC(cnt.v_syscall);
|
||
|
|
p = td->td_proc;
|
||
|
|
|
||
|
|
td->td_pticks = 0;
|
||
|
|
if (td->td_ucred != p->p_ucred)
|
||
|
|
cred_update_thread(td);
|
||
|
|
if (p->p_flag & P_TRACED) {
|
||
|
|
traced = 1;
|
||
|
|
PROC_LOCK(p);
|
||
|
|
td->td_dbgflags &= ~TDB_USERWR;
|
||
|
|
td->td_dbgflags |= TDB_SCE;
|
||
|
|
PROC_UNLOCK(p);
|
||
|
|
} else
|
||
|
|
traced = 0;
|
||
|
|
error = (p->p_sysent->sv_fetch_syscall_args)(td, sa);
|
||
|
|
#ifdef KTRACE
|
||
|
|
if (KTRPOINT(td, KTR_SYSCALL))
|
||
|
|
ktrsyscall(sa->code, sa->narg, sa->args);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
CTR6(KTR_SYSC,
|
||
|
|
"syscall: td=%p pid %d %s (%#lx, %#lx, %#lx)",
|
||
|
|
td, td->td_proc->p_pid, syscallname(p, sa->code),
|
||
|
|
sa->args[0], sa->args[1], sa->args[2]);
|
||
|
|
|
||
|
|
if (error == 0) {
|
||
|
|
STOPEVENT(p, S_SCE, sa->narg);
|
||
|
|
PTRACESTOP_SC(p, td, S_PT_SCE);
|
||
|
|
if (td->td_dbgflags & TDB_USERWR) {
|
||
|
|
/*
|
||
|
|
* Reread syscall number and arguments if
|
||
|
|
* debugger modified registers or memory.
|
||
|
|
*/
|
||
|
|
error = (p->p_sysent->sv_fetch_syscall_args)(td, sa);
|
||
|
|
#ifdef KTRACE
|
||
|
|
if (KTRPOINT(td, KTR_SYSCALL))
|
||
|
|
ktrsyscall(sa->code, sa->narg, sa->args);
|
||
|
|
#endif
|
||
|
|
if (error != 0)
|
||
|
|
goto retval;
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef CAPABILITY_MODE
|
||
|
|
/*
|
||
|
|
* In capability mode, we only allow access to system calls
|
||
|
|
* flagged with SYF_CAPENABLED.
|
||
|
|
*/
|
||
|
|
if (IN_CAPABILITY_MODE(td) &&
|
||
|
|
!(sa->callp->sy_flags & SYF_CAPENABLED)) {
|
||
|
|
error = ECAPMODE;
|
||
|
|
goto retval;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
error = syscall_thread_enter(td, sa->callp);
|
||
|
|
if (error != 0)
|
||
|
|
goto retval;
|
||
|
|
|
||
|
|
#ifdef KDTRACE_HOOKS
|
||
|
|
/*
|
||
|
|
* If the systrace module has registered it's probe
|
||
|
|
* callback and if there is a probe active for the
|
||
|
|
* syscall 'entry', process the probe.
|
||
|
|
*/
|
||
|
|
if (systrace_probe_func != NULL && sa->callp->sy_entry != 0)
|
||
|
|
(*systrace_probe_func)(sa->callp->sy_entry, sa->code,
|
||
|
|
sa->callp, sa->args, 0);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
AUDIT_SYSCALL_ENTER(sa->code, td);
|
||
|
|
error = (sa->callp->sy_call)(td, sa->args);
|
||
|
|
AUDIT_SYSCALL_EXIT(error, td);
|
||
|
|
|
||
|
|
/* Save the latest error return value. */
|
||
|
|
td->td_errno = error;
|
||
|
|
|
||
|
|
#ifdef KDTRACE_HOOKS
|
||
|
|
/*
|
||
|
|
* If the systrace module has registered it's probe
|
||
|
|
* callback and if there is a probe active for the
|
||
|
|
* syscall 'return', process the probe.
|
||
|
|
*/
|
||
|
|
if (systrace_probe_func != NULL && sa->callp->sy_return != 0)
|
||
|
|
(*systrace_probe_func)(sa->callp->sy_return, sa->code,
|
||
|
|
sa->callp, NULL, (error) ? -1 : td->td_retval[0]);
|
||
|
|
#endif
|
||
|
|
syscall_thread_exit(td, sa->callp);
|
||
|
|
CTR4(KTR_SYSC, "syscall: p=%p error=%d return %#lx %#lx",
|
||
|
|
p, error, td->td_retval[0], td->td_retval[1]);
|
||
|
|
}
|
||
|
|
retval:
|
||
|
|
if (traced) {
|
||
|
|
PROC_LOCK(p);
|
||
|
|
td->td_dbgflags &= ~TDB_SCE;
|
||
|
|
PROC_UNLOCK(p);
|
||
|
|
}
|
||
|
|
(p->p_sysent->sv_set_syscall_retval)(td, error);
|
||
|
|
return (error);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void
|
||
|
|
syscallret(struct thread *td, int error, struct syscall_args *sa __unused)
|
||
|
|
{
|
||
|
|
struct proc *p;
|
||
|
|
int traced;
|
||
|
|
|
||
|
|
p = td->td_proc;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Check for misbehavior.
|
||
|
|
*/
|
||
|
|
WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
|
||
|
|
syscallname(p, sa->code));
|
||
|
|
KASSERT(td->td_critnest == 0,
|
||
|
|
("System call %s returning in a critical section",
|
||
|
|
syscallname(p, sa->code)));
|
||
|
|
KASSERT(td->td_locks == 0,
|
||
|
|
("System call %s returning with %d locks held",
|
||
|
|
syscallname(p, sa->code), td->td_locks));
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Handle reschedule and other end-of-syscall issues
|
||
|
|
*/
|
||
|
|
userret(td, td->td_frame);
|
||
|
|
|
||
|
|
CTR4(KTR_SYSC, "syscall %s exit thread %p pid %d proc %s",
|
||
|
|
syscallname(p, sa->code), td, td->td_proc->p_pid, td->td_name);
|
||
|
|
|
||
|
|
#ifdef KTRACE
|
||
|
|
if (KTRPOINT(td, KTR_SYSRET))
|
||
|
|
ktrsysret(sa->code, error, td->td_retval[0]);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (p->p_flag & P_TRACED) {
|
||
|
|
traced = 1;
|
||
|
|
PROC_LOCK(p);
|
||
|
|
td->td_dbgflags |= TDB_SCX;
|
||
|
|
PROC_UNLOCK(p);
|
||
|
|
} else
|
||
|
|
traced = 0;
|
||
|
|
/*
|
||
|
|
* This works because errno is findable through the
|
||
|
|
* register set. If we ever support an emulation where this
|
||
|
|
* is not the case, this code will need to be revisited.
|
||
|
|
*/
|
||
|
|
STOPEVENT(p, S_SCX, sa->code);
|
||
|
|
PTRACESTOP_SC(p, td, S_PT_SCX);
|
||
|
|
if (traced || (td->td_dbgflags & (TDB_EXEC | TDB_FORK)) != 0) {
|
||
|
|
PROC_LOCK(p);
|
||
|
|
td->td_dbgflags &= ~(TDB_SCX | TDB_EXEC | TDB_FORK);
|
||
|
|
PROC_UNLOCK(p);
|
||
|
|
}
|
||
|
|
}
|