From 86e01d5addbd93d057433bc0bd8627ea54d2535b Mon Sep 17 00:00:00 2001
From: Tijl Coosemans <tijl@FreeBSD.org>
Date: Tue, 24 Jan 2017 16:13:59 +0000
Subject: [PATCH] Apply r210555 to 64 bit linux support:

The interpreter name should no longer be treated as a buffer that can be
overwritten.

PR:		216346
MFC after:	3 days
---
 sys/amd64/linux/linux_sysvec.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/sys/amd64/linux/linux_sysvec.c b/sys/amd64/linux/linux_sysvec.c
index c9f83027c64a..6e12d41a8f0e 100644
--- a/sys/amd64/linux/linux_sysvec.c
+++ b/sys/amd64/linux/linux_sysvec.c
@@ -718,7 +718,7 @@ exec_linux_imgact_try(struct image_params *imgp)
 {
 	const char *head = (const char *)imgp->image_header;
 	char *rpath;
-	int error = -1, len;
+	int error = -1;
 
 	/*
 	 * The interpreter for shell scripts run from a linux binary needs
@@ -736,17 +736,12 @@ exec_linux_imgact_try(struct image_params *imgp)
 			linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc),
 			    imgp->interpreter_name, UIO_SYSSPACE,
 			    &rpath, 0, AT_FDCWD);
-			if (rpath != NULL) {
-				len = strlen(rpath) + 1;
-
-				if (len <= MAXSHELLCMDLEN)
-					memcpy(imgp->interpreter_name,
-					    rpath, len);
-				free(rpath, M_TEMP);
-			}
+			if (rpath != NULL)
+				imgp->args->fname_buf =
+				    imgp->interpreter_name = rpath;
 		}
 	}
-	return(error);
+	return (error);
 }
 
 #define	LINUX_VSYSCALL_START		(-10UL << 20)