diff options
Diffstat (limited to 'sys/amd64/ia32')
-rw-r--r-- | sys/amd64/ia32/ia32_syscall.c | 149 |
1 files changed, 93 insertions, 56 deletions
diff --git a/sys/amd64/ia32/ia32_syscall.c b/sys/amd64/ia32/ia32_syscall.c index 5e20876..aa1ae6c 100644 --- a/sys/amd64/ia32/ia32_syscall.c +++ b/sys/amd64/ia32/ia32_syscall.c @@ -88,101 +88,136 @@ extern const char *freebsd32_syscallnames[]; void ia32_syscall(struct trapframe *frame); /* Called from asm code */ -void -ia32_syscall(struct trapframe *frame) -{ +struct ia32_syscall_args { + u_int code; caddr_t params; - int i; struct sysent *callp; - struct thread *td = curthread; - struct proc *p = td->td_proc; - register_t orig_tf_rflags; - int error; + u_int64_t args64[8]; int narg; +}; + +static int +fetch_ia32_syscall_args(struct thread *td, struct ia32_syscall_args *sa) +{ + struct proc *p; + struct trapframe *frame; u_int32_t args[8]; - u_int64_t args64[8]; - u_int code; - ksiginfo_t ksi; + int error, i; - PCPU_INC(cnt.v_syscall); - td->td_pticks = 0; - td->td_frame = frame; - if (td->td_ucred != p->p_ucred) - cred_update_thread(td); - params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t); - code = frame->tf_rax; - orig_tf_rflags = frame->tf_rflags; + p = td->td_proc; + frame = td->td_frame; + + sa->params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t); + sa->code = frame->tf_rax; if (p->p_sysent->sv_prepsyscall) { /* * The prep code is MP aware. */ - (*p->p_sysent->sv_prepsyscall)(frame, args, &code, ¶ms); + (*p->p_sysent->sv_prepsyscall)(frame, args, &sa->code, + &sa->params); } else { /* * Need to check if this is a 32 bit or 64 bit syscall. * fuword is MP aware. */ - if (code == SYS_syscall) { + if (sa->code == SYS_syscall) { /* * Code is first argument, followed by actual args. */ - code = fuword32(params); - params += sizeof(int); - } else if (code == SYS___syscall) { + sa->code = fuword32(sa->params); + sa->params += sizeof(int); + } else if (sa->code == SYS___syscall) { /* * Like syscall, but code is a quad, so as to maintain * quad alignment for the rest of the arguments. * We use a 32-bit fetch in case params is not * aligned. */ - code = fuword32(params); - params += sizeof(quad_t); + sa->code = fuword32(sa->params); + sa->params += sizeof(quad_t); } } - if (p->p_sysent->sv_mask) - code &= p->p_sysent->sv_mask; - - if (code >= p->p_sysent->sv_size) - callp = &p->p_sysent->sv_table[0]; + sa->code &= p->p_sysent->sv_mask; + if (sa->code >= p->p_sysent->sv_size) + sa->callp = &p->p_sysent->sv_table[0]; else - callp = &p->p_sysent->sv_table[code]; - - narg = callp->sy_narg; + sa->callp = &p->p_sysent->sv_table[sa->code]; + sa->narg = sa->callp->sy_narg; - /* - * copyin and the ktrsyscall()/ktrsysret() code is MP-aware - */ - if (params != NULL && narg != 0) - error = copyin(params, (caddr_t)args, - (u_int)(narg * sizeof(int))); + if (sa->params != NULL && sa->narg != 0) + error = copyin(sa->params, (caddr_t)args, + (u_int)(sa->narg * sizeof(int))); else error = 0; - for (i = 0; i < narg; i++) - args64[i] = args[i]; + for (i = 0; i < sa->narg; i++) + sa->args64[i] = args[i]; #ifdef KTRACE if (KTRPOINT(td, KTR_SYSCALL)) - ktrsyscall(code, narg, args64); + ktrsyscall(sa->code, sa->narg, sa->args64); #endif + + return (error); +} + +void +ia32_syscall(struct trapframe *frame) +{ + struct thread *td; + struct proc *p; + struct ia32_syscall_args sa; + register_t orig_tf_rflags; + int error; + ksiginfo_t ksi; + + PCPU_INC(cnt.v_syscall); + td = curthread; + p = td->td_proc; + td->td_syscalls++; + + td->td_pticks = 0; + td->td_frame = frame; + if (td->td_ucred != p->p_ucred) + cred_update_thread(td); + orig_tf_rflags = frame->tf_rflags; + if (p->p_flag & P_TRACED) { + PROC_LOCK(p); + td->td_dbgflags &= ~TDB_USERWR; + PROC_UNLOCK(p); + } + error = fetch_ia32_syscall_args(td, &sa); + CTR4(KTR_SYSC, "syscall enter thread %p pid %d proc %s code %d", td, - td->td_proc->p_pid, td->td_proc->p_comm, code); + td->td_proc->p_pid, td->td_name, sa.code); if (error == 0) { td->td_retval[0] = 0; td->td_retval[1] = frame->tf_rdx; - STOPEVENT(p, S_SCE, narg); - + 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 = fetch_ia32_syscall_args(td, &sa); + if (error != 0) + goto retval; + td->td_retval[1] = frame->tf_rdx; + } - AUDIT_SYSCALL_ENTER(code, td); - error = (*callp->sy_call)(td, args64); + AUDIT_SYSCALL_ENTER(sa.code, td); + error = (*sa.callp->sy_call)(td, sa.args64); AUDIT_SYSCALL_EXIT(error, td); - } + /* Save the latest error return value. */ + td->td_errno = error; + } + retval: cpu_set_syscall_retval(td, error); /* @@ -201,14 +236,16 @@ ia32_syscall(struct trapframe *frame) * Check for misbehavior. */ WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning", - (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???"); + (sa.code >= 0 && sa.code < SYS_MAXSYSCALL) ? + freebsd32_syscallnames[sa.code] : "???"); KASSERT(td->td_critnest == 0, ("System call %s returning in a critical section", - (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???")); + (sa.code >= 0 && sa.code < SYS_MAXSYSCALL) ? + freebsd32_syscallnames[sa.code] : "???")); KASSERT(td->td_locks == 0, ("System call %s returning with %d locks held", - (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???", - td->td_locks)); + (sa.code >= 0 && sa.code < SYS_MAXSYSCALL) ? + freebsd32_syscallnames[sa.code] : "???", td->td_locks)); /* * Handle reschedule and other end-of-syscall issues @@ -216,10 +253,10 @@ ia32_syscall(struct trapframe *frame) userret(td, frame); CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td, - td->td_proc->p_pid, td->td_proc->p_comm, code); + td->td_proc->p_pid, td->td_proc->p_comm, sa.code); #ifdef KTRACE if (KTRPOINT(td, KTR_SYSRET)) - ktrsysret(code, error, td->td_retval[0]); + ktrsysret(sa.code, error, td->td_retval[0]); #endif /* @@ -227,7 +264,7 @@ ia32_syscall(struct trapframe *frame) * 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, code); + STOPEVENT(p, S_SCX, sa.code); PTRACESTOP_SC(p, td, S_PT_SCX); } |