X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=arch%2Farm%2Fkernel%2Fprocess.c;h=92f7b15dd22121d4aa674fd78cd95cac8924c07f;hb=6eb37eb276f0b91adb43b853ce6fb0812fbf0883;hp=94f6b05f9e24e8cd1d79063f03a9b2dd16791c67;hpb=7b77d161ce7e480a660692cab079712fc0268ba2;p=firefly-linux-kernel-4.4.55.git

diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 94f6b05f9e24..92f7b15dd221 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -404,6 +404,7 @@ EXPORT_SYMBOL(dump_fpu);
 unsigned long get_wchan(struct task_struct *p)
 {
 	struct stackframe frame;
+	unsigned long stack_page;
 	int count = 0;
 	if (!p || p == current || p->state == TASK_RUNNING)
 		return 0;
@@ -412,9 +413,11 @@ unsigned long get_wchan(struct task_struct *p)
 	frame.sp = thread_saved_sp(p);
 	frame.lr = 0;			/* recovered from the stack */
 	frame.pc = thread_saved_pc(p);
+	stack_page = (unsigned long)task_stack_page(p);
 	do {
-		int ret = unwind_frame(&frame);
-		if (ret < 0)
+		if (frame.sp < stack_page ||
+		    frame.sp >= stack_page + THREAD_SIZE ||
+		    unwind_frame(&frame) < 0)
 			return 0;
 		if (!in_sched_functions(frame.pc))
 			return frame.pc;