[src/trunk]: src/sys/arch/powerpc/booke Let copyinstr(9) return ENAMETOOLONG ...

[rin <rin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e488094d5800
branches:  trunk
changeset: 745433:e488094d5800
user:      rin <rin%NetBSD.org@localhost>
date:      Mon Mar 02 03:34:28 2020 +0000

description:
Let copyinstr(9) return ENAMETOOLONG correctly if source is not
NUL-terminated; it cannot be determined by (uint8_t)data == '\0'
since data is right shifted at the end of loop.

Found by POOL_REDZONE.

diffstat:

 sys/arch/powerpc/booke/copyin.c |  16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)

diffs (55 lines):

diff -r 1409b834c726 -r e488094d5800 sys/arch/powerpc/booke/copyin.c
--- a/sys/arch/powerpc/booke/copyin.c   Mon Mar 02 01:46:02 2020 +0000
+++ b/sys/arch/powerpc/booke/copyin.c   Mon Mar 02 03:34:28 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: copyin.c,v 1.7 2019/04/07 05:25:55 thorpej Exp $       */
+/*     $NetBSD: copyin.c,v 1.8 2020/03/02 03:34:28 rin Exp $   */
 
 /*-
  * Copyright (c) 2010, 2011 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: copyin.c,v 1.7 2019/04/07 05:25:55 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: copyin.c,v 1.8 2020/03/02 03:34:28 rin Exp $");
 
 #define        __UFETCHSTORE_PRIVATE
 
@@ -306,6 +306,7 @@
 {
        struct pcb * const pcb = lwp_getpcb(curlwp);
        struct faultbuf env;
+       int rv;
 
        if (__predict_false(len == 0)) {
                if (done)
@@ -313,7 +314,7 @@
                return 0;
        }
 
-       int rv = setfault(&env);
+       rv = setfault(&env);
        if (rv != 0) {
                pcb->pcb_onfault = NULL;
                if (done)
@@ -346,15 +347,14 @@
                *kdaddr8++ = data;
                if ((uint8_t) data == 0) {
                        copylen++;
-                       break;
+                       goto out;
                }
        }
+       rv = ENAMETOOLONG;
 
+out:
        pcb->pcb_onfault = NULL;
        if (done)
                *done = copylen;
-       /*
-        * If the last byte is not NUL (0), then the name is too long.
-        */
-       return (uint8_t)data ? ENAMETOOLONG : 0;
+       return rv;
 }