[PATCH] WE-22 : prevent information leak on 64 bit
Johannes Berg discovered that kernel space was leaking to
userspace on 64 bit platform. He made a first patch to fix that. This
is an improved version of his patch.
Signed-off-by: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/wireless.h b/include/linux/wireless.h
index 447c52b..48759b2 100644
--- a/include/linux/wireless.h
+++ b/include/linux/wireless.h
@@ -1,10 +1,10 @@
/*
* This file define a set of standard wireless extensions
*
- * Version : 21 14.3.06
+ * Version : 22 16.3.07
*
* Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
- * Copyright (c) 1997-2006 Jean Tourrilhes, All Rights Reserved.
+ * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
*/
#ifndef _LINUX_WIRELESS_H
@@ -85,7 +85,7 @@
* (there is some stuff that will be added in the future...)
* I just plan to increment with each new version.
*/
-#define WIRELESS_EXT 21
+#define WIRELESS_EXT 22
/*
* Changes :
@@ -221,6 +221,10 @@
* - Add IW_RETRY_SHORT/IW_RETRY_LONG retry modifiers
* - Power/Retry relative values no longer * 100000
* - Add explicit flag to tell stats are in 802.11k RCPI : IW_QUAL_RCPI
+ *
+ * V21 to V22
+ * ----------
+ * - Prevent leaking of kernel space in stream on 64 bits.
*/
/**************************** CONSTANTS ****************************/
@@ -1085,4 +1089,15 @@
#define IW_EV_POINT_LEN (IW_EV_LCP_LEN + sizeof(struct iw_point) - \
IW_EV_POINT_OFF)
+/* Size of the Event prefix when packed in stream */
+#define IW_EV_LCP_PK_LEN (4)
+/* Size of the various events when packed in stream */
+#define IW_EV_CHAR_PK_LEN (IW_EV_LCP_PK_LEN + IFNAMSIZ)
+#define IW_EV_UINT_PK_LEN (IW_EV_LCP_PK_LEN + sizeof(__u32))
+#define IW_EV_FREQ_PK_LEN (IW_EV_LCP_PK_LEN + sizeof(struct iw_freq))
+#define IW_EV_PARAM_PK_LEN (IW_EV_LCP_PK_LEN + sizeof(struct iw_param))
+#define IW_EV_ADDR_PK_LEN (IW_EV_LCP_PK_LEN + sizeof(struct sockaddr))
+#define IW_EV_QUAL_PK_LEN (IW_EV_LCP_PK_LEN + sizeof(struct iw_quality))
+#define IW_EV_POINT_PK_LEN (IW_EV_LCP_LEN + 4)
+
#endif /* _LINUX_WIRELESS_H */
diff --git a/include/net/iw_handler.h b/include/net/iw_handler.h
index 10559e9..8a83018 100644
--- a/include/net/iw_handler.h
+++ b/include/net/iw_handler.h
@@ -1,10 +1,10 @@
/*
* This file define the new driver API for Wireless Extensions
*
- * Version : 7 18.3.05
+ * Version : 8 16.3.07
*
* Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
- * Copyright (c) 2001-2006 Jean Tourrilhes, All Rights Reserved.
+ * Copyright (c) 2001-2007 Jean Tourrilhes, All Rights Reserved.
*/
#ifndef _IW_HANDLER_H
@@ -207,7 +207,7 @@
* will be needed...
* I just plan to increment with each new version.
*/
-#define IW_HANDLER_VERSION 7
+#define IW_HANDLER_VERSION 8
/*
* Changes :
@@ -239,6 +239,10 @@
* - Remove (struct iw_point *)->pointer from events and streams
* - Remove spy_offset from struct iw_handler_def
* - Add "check" version of event macros for ieee802.11 stack
+ *
+ * V7 to V8
+ * ----------
+ * - Prevent leaking of kernel space in stream on 64 bits.
*/
/**************************** CONSTANTS ****************************/
@@ -500,7 +504,11 @@
/* Check if it's possible */
if(likely((stream + event_len) < ends)) {
iwe->len = event_len;
- memcpy(stream, (char *) iwe, event_len);
+ /* Beware of alignement issues on 64 bits */
+ memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
+ memcpy(stream + IW_EV_LCP_LEN,
+ ((char *) iwe) + IW_EV_LCP_LEN,
+ event_len - IW_EV_LCP_LEN);
stream += event_len;
}
return stream;
@@ -521,10 +529,10 @@
/* Check if it's possible */
if(likely((stream + event_len) < ends)) {
iwe->len = event_len;
- memcpy(stream, (char *) iwe, IW_EV_LCP_LEN);
+ memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
memcpy(stream + IW_EV_LCP_LEN,
((char *) iwe) + IW_EV_LCP_LEN + IW_EV_POINT_OFF,
- IW_EV_POINT_LEN - IW_EV_LCP_LEN);
+ IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
memcpy(stream + IW_EV_POINT_LEN, extra, iwe->u.data.length);
stream += event_len;
}
@@ -574,7 +582,11 @@
/* Check if it's possible, set error if not */
if(likely((stream + event_len) < ends)) {
iwe->len = event_len;
- memcpy(stream, (char *) iwe, event_len);
+ /* Beware of alignement issues on 64 bits */
+ memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
+ memcpy(stream + IW_EV_LCP_LEN,
+ ((char *) iwe) + IW_EV_LCP_LEN,
+ event_len - IW_EV_LCP_LEN);
stream += event_len;
} else
*perr = -E2BIG;
@@ -598,10 +610,10 @@
/* Check if it's possible */
if(likely((stream + event_len) < ends)) {
iwe->len = event_len;
- memcpy(stream, (char *) iwe, IW_EV_LCP_LEN);
+ memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
memcpy(stream + IW_EV_LCP_LEN,
((char *) iwe) + IW_EV_LCP_LEN + IW_EV_POINT_OFF,
- IW_EV_POINT_LEN - IW_EV_LCP_LEN);
+ IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
memcpy(stream + IW_EV_POINT_LEN, extra, iwe->u.data.length);
stream += event_len;
} else
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 6055074..33ea8ea 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -621,7 +621,8 @@
if (err < 0)
goto errout;
- iw += IW_EV_POINT_OFF;
+ /* Payload is at an offset in buffer */
+ iw = iw_buf + IW_EV_POINT_OFF;
}
#endif /* CONFIG_NET_WIRELESS_RTNETLINK */
diff --git a/net/core/wireless.c b/net/core/wireless.c
index 9936ab1..b07fe27 100644
--- a/net/core/wireless.c
+++ b/net/core/wireless.c
@@ -2,7 +2,7 @@
* This file implement the Wireless Extensions APIs.
*
* Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
- * Copyright (c) 1997-2006 Jean Tourrilhes, All Rights Reserved.
+ * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
*
* (As all part of the Linux kernel, this file is GPL)
*/
@@ -76,6 +76,9 @@
* o Change length in ESSID and NICK to strlen() instead of strlen()+1
* o Make standard_ioctl_num and standard_event_num unsigned
* o Remove (struct net_device *)->get_wireless_stats()
+ *
+ * v10 - 16.3.07 - Jean II
+ * o Prevent leaking of kernel space in stream on 64 bits.
*/
/***************************** INCLUDES *****************************/
@@ -427,6 +430,21 @@
IW_EV_QUAL_LEN, /* IW_HEADER_TYPE_QUAL */
};
+/* Size (in bytes) of various events, as packed */
+static const int event_type_pk_size[] = {
+ IW_EV_LCP_PK_LEN, /* IW_HEADER_TYPE_NULL */
+ 0,
+ IW_EV_CHAR_PK_LEN, /* IW_HEADER_TYPE_CHAR */
+ 0,
+ IW_EV_UINT_PK_LEN, /* IW_HEADER_TYPE_UINT */
+ IW_EV_FREQ_PK_LEN, /* IW_HEADER_TYPE_FREQ */
+ IW_EV_ADDR_PK_LEN, /* IW_HEADER_TYPE_ADDR */
+ 0,
+ IW_EV_POINT_PK_LEN, /* Without variable payload */
+ IW_EV_PARAM_PK_LEN, /* IW_HEADER_TYPE_PARAM */
+ IW_EV_QUAL_PK_LEN, /* IW_HEADER_TYPE_QUAL */
+};
+
/************************ COMMON SUBROUTINES ************************/
/*
* Stuff that may be used in various place or doesn't fit in one
@@ -1217,7 +1235,7 @@
memcpy(buffer + IW_EV_POINT_OFF, request, request_len);
/* Use our own copy of wrqu */
wrqu = (union iwreq_data *) (buffer + IW_EV_POINT_OFF
- + IW_EV_LCP_LEN);
+ + IW_EV_LCP_PK_LEN);
/* No extra arguments. Trivial to handle */
ret = handler(dev, &info, wrqu, NULL);
@@ -1229,8 +1247,8 @@
/* Get a temp copy of wrqu (skip pointer) */
memcpy(((char *) &wrqu_point) + IW_EV_POINT_OFF,
- ((char *) request) + IW_EV_LCP_LEN,
- IW_EV_POINT_LEN - IW_EV_LCP_LEN);
+ ((char *) request) + IW_EV_LCP_PK_LEN,
+ IW_EV_POINT_LEN - IW_EV_LCP_PK_LEN);
/* Calculate space needed by arguments. Always allocate
* for max space. Easier, and won't last long... */
@@ -1240,7 +1258,7 @@
(wrqu_point.data.length > descr->max_tokens))
extra_size = (wrqu_point.data.length
* descr->token_size);
- buffer_size = extra_size + IW_EV_POINT_LEN + IW_EV_POINT_OFF;
+ buffer_size = extra_size + IW_EV_POINT_PK_LEN + IW_EV_POINT_OFF;
#ifdef WE_RTNETLINK_DEBUG
printk(KERN_DEBUG "%s (WE.r) : Malloc %d bytes (%d bytes)\n",
dev->name, extra_size, buffer_size);
@@ -1254,15 +1272,15 @@
/* Put wrqu in the right place (just before extra).
* Leave space for IWE header and dummy pointer...
- * Note that IW_EV_LCP_LEN==4 bytes, so it's still aligned...
+ * Note that IW_EV_LCP_PK_LEN==4 bytes, so it's still aligned.
*/
- memcpy(buffer + IW_EV_LCP_LEN + IW_EV_POINT_OFF,
+ memcpy(buffer + IW_EV_LCP_PK_LEN + IW_EV_POINT_OFF,
((char *) &wrqu_point) + IW_EV_POINT_OFF,
- IW_EV_POINT_LEN - IW_EV_LCP_LEN);
- wrqu = (union iwreq_data *) (buffer + IW_EV_LCP_LEN);
+ IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
+ wrqu = (union iwreq_data *) (buffer + IW_EV_LCP_PK_LEN);
/* Extra comes logically after that. Offset +12 bytes. */
- extra = buffer + IW_EV_POINT_OFF + IW_EV_POINT_LEN;
+ extra = buffer + IW_EV_POINT_OFF + IW_EV_POINT_PK_LEN;
/* Call the handler */
ret = handler(dev, &info, wrqu, extra);
@@ -1270,11 +1288,11 @@
/* Calculate real returned length */
extra_size = (wrqu->data.length * descr->token_size);
/* Re-adjust reply size */
- request->len = extra_size + IW_EV_POINT_LEN;
+ request->len = extra_size + IW_EV_POINT_PK_LEN;
/* Put the iwe header where it should, i.e. scrap the
* dummy pointer. */
- memcpy(buffer + IW_EV_POINT_OFF, request, IW_EV_LCP_LEN);
+ memcpy(buffer + IW_EV_POINT_OFF, request, IW_EV_LCP_PK_LEN);
#ifdef WE_RTNETLINK_DEBUG
printk(KERN_DEBUG "%s (WE.r) : Reply 0x%04X, hdr_len %d, tokens %d, extra_size %d, buffer_size %d\n", dev->name, cmd, hdr_len, wrqu->data.length, extra_size, buffer_size);
@@ -1331,10 +1349,10 @@
#endif /* WE_RTNETLINK_DEBUG */
/* Extract fixed header from request. This is properly aligned. */
- wrqu = &request->u;
+ wrqu = (union iwreq_data *) (((char *) request) + IW_EV_LCP_PK_LEN);
/* Check if wrqu is complete */
- hdr_len = event_type_size[descr->header_type];
+ hdr_len = event_type_pk_size[descr->header_type];
if(request_len < hdr_len) {
#ifdef WE_RTNETLINK_DEBUG
printk(KERN_DEBUG
@@ -1359,7 +1377,7 @@
/* Put wrqu in the right place (skip pointer) */
memcpy(((char *) &wrqu_point) + IW_EV_POINT_OFF,
- wrqu, IW_EV_POINT_LEN - IW_EV_LCP_LEN);
+ wrqu, IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
/* Don't forget about the event code... */
wrqu = &wrqu_point;
@@ -1483,7 +1501,7 @@
hdr_len = extra_size;
extra_size = 0;
} else {
- hdr_len = IW_EV_POINT_LEN;
+ hdr_len = IW_EV_POINT_PK_LEN;
}
/* Check if wrqu is complete */
@@ -1514,7 +1532,7 @@
memcpy(buffer + IW_EV_POINT_OFF, request, request_len);
/* Use our own copy of wrqu */
wrqu = (union iwreq_data *) (buffer + IW_EV_POINT_OFF
- + IW_EV_LCP_LEN);
+ + IW_EV_LCP_PK_LEN);
/* No extra arguments. Trivial to handle */
ret = handler(dev, &info, wrqu, (char *) wrqu);
@@ -1523,7 +1541,7 @@
char * extra;
/* Buffer for full reply */
- buffer_size = extra_size + IW_EV_POINT_LEN + IW_EV_POINT_OFF;
+ buffer_size = extra_size + IW_EV_POINT_PK_LEN + IW_EV_POINT_OFF;
#ifdef WE_RTNETLINK_DEBUG
printk(KERN_DEBUG "%s (WE.r) : Malloc %d bytes (%d bytes)\n",
@@ -1538,15 +1556,15 @@
/* Put wrqu in the right place (just before extra).
* Leave space for IWE header and dummy pointer...
- * Note that IW_EV_LCP_LEN==4 bytes, so it's still aligned...
+ * Note that IW_EV_LCP_PK_LEN==4 bytes, so it's still aligned.
*/
- memcpy(buffer + IW_EV_LCP_LEN + IW_EV_POINT_OFF,
- ((char *) request) + IW_EV_LCP_LEN,
- IW_EV_POINT_LEN - IW_EV_LCP_LEN);
- wrqu = (union iwreq_data *) (buffer + IW_EV_LCP_LEN);
+ memcpy(buffer + IW_EV_LCP_PK_LEN + IW_EV_POINT_OFF,
+ ((char *) request) + IW_EV_LCP_PK_LEN,
+ IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
+ wrqu = (union iwreq_data *) (buffer + IW_EV_LCP_PK_LEN);
/* Extra comes logically after that. Offset +12 bytes. */
- extra = buffer + IW_EV_POINT_OFF + IW_EV_POINT_LEN;
+ extra = buffer + IW_EV_POINT_OFF + IW_EV_POINT_PK_LEN;
/* Call the handler */
ret = handler(dev, &info, wrqu, extra);
@@ -1556,11 +1574,11 @@
if (!(descr->get_args & IW_PRIV_SIZE_FIXED))
extra_size = adjust_priv_size(descr->get_args, wrqu);
/* Re-adjust reply size */
- request->len = extra_size + IW_EV_POINT_LEN;
+ request->len = extra_size + IW_EV_POINT_PK_LEN;
/* Put the iwe header where it should, i.e. scrap the
* dummy pointer. */
- memcpy(buffer + IW_EV_POINT_OFF, request, IW_EV_LCP_LEN);
+ memcpy(buffer + IW_EV_POINT_OFF, request, IW_EV_LCP_PK_LEN);
#ifdef WE_RTNETLINK_DEBUG
printk(KERN_DEBUG "%s (WE.r) : Reply 0x%04X, hdr_len %d, tokens %d, extra_size %d, buffer_size %d\n", dev->name, cmd, hdr_len, wrqu->data.length, extra_size, buffer_size);
@@ -1641,14 +1659,14 @@
/* Does it fits in wrqu ? */
if((descr->set_args & IW_PRIV_SIZE_FIXED) &&
(extra_size <= IFNAMSIZ)) {
- hdr_len = IW_EV_LCP_LEN + extra_size;
+ hdr_len = IW_EV_LCP_PK_LEN + extra_size;
extra_size = 0;
} else {
- hdr_len = IW_EV_POINT_LEN;
+ hdr_len = IW_EV_POINT_PK_LEN;
}
/* Extract fixed header from request. This is properly aligned. */
- wrqu = &request->u;
+ wrqu = (union iwreq_data *) (((char *) request) + IW_EV_LCP_PK_LEN);
/* Check if wrqu is complete */
if(request_len < hdr_len) {
@@ -1675,7 +1693,7 @@
/* Put wrqu in the right place (skip pointer) */
memcpy(((char *) &wrqu_point) + IW_EV_POINT_OFF,
- wrqu, IW_EV_POINT_LEN - IW_EV_LCP_LEN);
+ wrqu, IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
/* Does it fits within bounds ? */
if(wrqu_point.data.length > (descr->set_args &
@@ -1738,7 +1756,7 @@
iw_handler handler;
/* Check length */
- if(len < IW_EV_LCP_LEN) {
+ if(len < IW_EV_LCP_PK_LEN) {
printk(KERN_DEBUG "%s (WE.r) : RtNetlink request too short (%d)\n",
dev->name, len);
return -EINVAL;
@@ -1822,7 +1840,7 @@
iw_handler handler;
/* Check length */
- if(len < IW_EV_LCP_LEN) {
+ if(len < IW_EV_LCP_PK_LEN) {
printk(KERN_DEBUG "%s (WE.r) : RtNetlink request too short (%d)\n",
dev->name, len);
return -EINVAL;