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Fix a couple of bugs in the fasttrap emulation of a "push %rbp" instruction:

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the code was trying to save the stack pointer rather than the frame pointer,
and the arguments to copyout(9) were reversed, so nothing ended up being
saved on the stack. This would cause process crashes when the pid provider
was being used to instrument calls of a function starting with this
instruction.

Reported by:	symbolics@gmx.com
Tested by:	symbolics@gmx.com (earlier version)
MFC after:	2 weeks
This commit is contained in:
Mark Johnston 2013-10-26 03:21:54 +00:00
parent 4ff9a7ef08
commit 165de3f338
1 changed files with 6 additions and 7 deletions
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13
sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c
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@ -104,6 +104,7 @@ uwrite(proc_t *p, void *kaddr, size_t len, uintptr_t uaddr)
#define r_rip r_eip
#define r_rflags r_eflags
#define r_rsp r_esp
#define r_rbp r_ebp
#endif
/*
@ -1394,29 +1395,27 @@ fasttrap_pid_probe(struct reg *rp)
case FASTTRAP_T_PUSHL_EBP:
{
int ret = 0;
uintptr_t addr = 0;
#ifdef __amd64
if (p->p_model == DATAMODEL_NATIVE) {
addr = rp->r_rsp - sizeof (uintptr_t);
ret = fasttrap_sulword((void *)addr, &rp->r_rsp);
rp->r_rsp -= sizeof (uintptr_t);
ret = fasttrap_sulword(&rp->r_rbp, (void *)rp->r_rsp);
} else {
#endif
#ifdef __i386__
addr = rp->r_rsp - sizeof (uint32_t);
ret = fasttrap_suword32((void *)addr, &rp->r_rsp);
rp->r_rsp -= sizeof (uint32_t);
ret = fasttrap_suword32(&rp->r_rbp, (void *)rp->r_rsp);
#endif
#ifdef __amd64
}
#endif
if (ret == -1) {
fasttrap_sigsegv(p, curthread, addr);
fasttrap_sigsegv(p, curthread, rp->r_rsp);
new_pc = pc;
break;
}
rp->r_rsp = addr;
new_pc = pc + tp->ftt_size;
break;
}