diff options
Diffstat (limited to 'sys/amd64/ia32')
| -rw-r--r-- | sys/amd64/ia32/ia32_signal.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/sys/amd64/ia32/ia32_signal.c b/sys/amd64/ia32/ia32_signal.c index 30074e8..ae5978e 100644 --- a/sys/amd64/ia32/ia32_signal.c +++ b/sys/amd64/ia32/ia32_signal.c @@ -558,3 +558,44 @@ freebsd32_sigreturn(td, uap) PROC_UNLOCK(p); return (EJUSTRETURN); } + +/* + * Clear registers on exec + */ +void +ia32_setregs(td, entry, stack, ps_strings) + struct thread *td; + u_long entry; + u_long stack; + u_long ps_strings; +{ + struct trapframe *regs = td->td_frame; + struct pcb *pcb = td->td_pcb; + + wrmsr(MSR_FSBASE, 0); + wrmsr(MSR_KGSBASE, 0); /* User value while we're in the kernel */ + pcb->pcb_fsbase = 0; + pcb->pcb_gsbase = 0; + load_ds(_udatasel); + load_es(_udatasel); + load_fs(_udatasel); + load_gs(_udatasel); + pcb->pcb_ds = _udatasel; + pcb->pcb_es = _udatasel; + pcb->pcb_fs = _udatasel; + pcb->pcb_gs = _udatasel; + + bzero((char *)regs, sizeof(struct trapframe)); + regs->tf_rip = entry; + regs->tf_rsp = stack; + regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); + regs->tf_ss = _udatasel; + regs->tf_cs = _ucode32sel; + regs->tf_rbx = ps_strings; + load_cr0(rcr0() | CR0_MP | CR0_TS); + fpstate_drop(td); + + /* Return via doreti so that we can change to a different %cs */ + pcb->pcb_flags |= PCB_FULLCTX; + td->td_retval[1] = 0; +} |
