[PATCH 2/2] i386/i386/fpu.c: check machine state before setting fp_valid

[Marin Ramesa]

When fp_thread is not NULL and is not the current thread, and fp_save() does
not alter the machine state, check if ifps is NULL before setting fp_valid
to avoid dereference of null pointer. 

* i386/i386/fpu.c (ifps): Check if it's NULL.

---
 i386/i386/fpu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/i386/i386/fpu.c b/i386/i386/fpu.c
index fb2c8ce..226f4ea 100644
--- a/i386/i386/fpu.c
+++ b/i386/i386/fpu.c
@@ -640,7 +640,8 @@ fphandleerr()
             */
            clear_ts();
            fp_save(fp_thread);
-           fp_thread->pcb->ims.ifps->fp_valid = 2;
+           if (fp_thread->pcb->ims.ifps != NULL)       
+               fp_thread->pcb->ims.ifps->fp_valid = 2;
            fninit();
            clear_fpu();
            /* leave fp_intr_thread THREAD_NULL */
-- 
1.8.1.4