From: Dmitry V. Levin <ldv@altlinux.org>
Date: Fri, 27 May 2016 00:42:18 +0000 (+0000)
Subject: evdev.c: fix decoding of EVIOCGNAME, EVIOCGPHYS, and EVIOCGUNIQ
X-Git-Tag: v4.12~18
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=10de2eb030ed48036eba638d9477a3151df232d0;p=strace

evdev.c: fix decoding of EVIOCGNAME, EVIOCGPHYS, and EVIOCGUNIQ

* evdev.c (evdev_read_ioctl): Fix printing of the string returned
in response to EVIOCGNAME, EVIOCGPHYS, and EVIOCGUNIQ requests.
---

diff --git a/evdev.c b/evdev.c
index b889bb99..2d10d8b2 100644
--- a/evdev.c
+++ b/evdev.c
@@ -382,9 +382,6 @@ bit_ioctl(struct tcb *tcp, const unsigned int ev_nr, const long arg)
 static int
 evdev_read_ioctl(struct tcb *tcp, const unsigned int code, const long arg)
 {
-	if (syserror(tcp))
-		return 0;
-
 	/* fixed-number fixed-length commands */
 	switch (code) {
 		case EVIOCGVERSION:
@@ -419,7 +416,10 @@ evdev_read_ioctl(struct tcb *tcp, const unsigned int code, const long arg)
 		case _IOC_NR(EVIOCGPHYS(0)):
 		case _IOC_NR(EVIOCGUNIQ(0)):
 			tprints(", ");
-			printstr(tcp, arg, tcp->u_rval - 1);
+			if (syserror(tcp))
+				printaddr(arg);
+			else
+				printstr(tcp, arg, tcp->u_rval);
 			return 1;
 # ifdef EVIOCGPROP
 		case _IOC_NR(EVIOCGPROP(0)):