Fixes for ptrace(PT_GETXSTATE_INFO) related to the padding in struct

ptrace_xstate_info).

struct ptrace_xstate_info has 64bit member but ends up with 32bit
one. As result, on amd64 there is a 32bit padding at the end, but not
on i386.

We must clear the padding before doing the copyout. For compat32 case,
we must copyout the structure which does not have the padding at the
end.  The later fixes 32bit gdb display of the YMM registers when
running on amd64 kernel.

Reported by:	Vlad Tsyrklevich
Reviewed by:	brooks (previous version)
Sponsored by:	The FreeBSD Foundation
admbugs:	765
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D14794
This commit is contained in:
kib 2018-03-22 20:44:27 +00:00
parent bcda73b875
commit d93ae96f8a

View File

@ -45,10 +45,20 @@ __FBSDID("$FreeBSD$");
#include <machine/frame.h>
#include <machine/vmparam.h>
#ifdef COMPAT_FREEBSD32
struct ptrace_xstate_info32 {
uint32_t xsave_mask1, xsave_mask2;
uint32_t xsave_len;
};
#endif
static int
cpu_ptrace_xstate(struct thread *td, int req, void *addr, int data)
{
struct ptrace_xstate_info info;
#ifdef COMPAT_FREEBSD32
struct ptrace_xstate_info32 info32;
#endif
char *savefpu;
int error;
@ -78,13 +88,28 @@ cpu_ptrace_xstate(struct thread *td, int req, void *addr, int data)
break;
case PT_GETXSTATE_INFO:
if (data != sizeof(info)) {
error = EINVAL;
break;
#ifdef COMPAT_FREEBSD32
if (SV_CURPROC_FLAG(SV_ILP32)) {
if (data != sizeof(info32)) {
error = EINVAL;
} else {
info32.xsave_len = cpu_max_ext_state_size;
info32.xsave_mask1 = xsave_mask;
info32.xsave_mask2 = xsave_mask >> 32;
error = copyout(&info32, addr, data);
}
} else
#endif
{
if (data != sizeof(info)) {
error = EINVAL;
} else {
bzero(&info, sizeof(info));
info.xsave_len = cpu_max_ext_state_size;
info.xsave_mask = xsave_mask;
error = copyout(&info, addr, data);
}
}
info.xsave_len = cpu_max_ext_state_size;
info.xsave_mask = xsave_mask;
error = copyout(&info, addr, data);
break;
case PT_GETXSTATE: