blob: ce4d3d989098e508098edf52a21f459f116fa7f3 [file] [log] [blame]
From 5ad707ddf33d1d785a8ca1fbeec91d2eee985820 Mon Sep 17 00:00:00 2001
From: Hardening <rdp.effort@gmail.com>
Date: Fri, 6 Jun 2014 23:24:16 +0200
Subject: [PATCH] Fix CVE-2014-0250
This patch fixes CVE-2014-0250 by checking width, height and bpp when
receiving a new pointer.
---
client/X11/xf_cliprdr.c | 11 +++++--
libfreerdp/core/fastpath.c | 2 +-
libfreerdp/core/orders.c | 21 ++++++++++++
libfreerdp/core/surface.c | 6 ++++
libfreerdp/core/update.c | 82 +++++++++++++++++++++++++++++++++++++++-------
libfreerdp/core/update.h | 2 +-
libfreerdp/core/window.c | 5 +++
7 files changed, 114 insertions(+), 15 deletions(-)
diff --git a/client/X11/xf_cliprdr.c b/client/X11/xf_cliprdr.c
index 19c4332..8fb49f9 100644
--- a/client/X11/xf_cliprdr.c
+++ b/client/X11/xf_cliprdr.c
@@ -914,7 +914,7 @@ static void xf_cliprdr_process_unicodetext(clipboardContext* cb, BYTE* data, int
crlf2lf(cb->data, &cb->data_length);
}
-static void xf_cliprdr_process_dib(clipboardContext* cb, BYTE* data, int size)
+static BOOL xf_cliprdr_process_dib(clipboardContext* cb, BYTE* data, int size)
{
wStream* s;
UINT16 bpp;
@@ -926,12 +926,18 @@ static void xf_cliprdr_process_dib(clipboardContext* cb, BYTE* data, int size)
if (size < 40)
{
DEBUG_X11_CLIPRDR("dib size %d too short", size);
- return;
+ return FALSE;
}
s = Stream_New(data, size);
Stream_Seek(s, 14);
Stream_Read_UINT16(s, bpp);
+ if ((bpp < 1) || (bpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bpp value %d", __FUNCTION__, bpp);
+ return FALSE;
+ }
+
Stream_Read_UINT32(s, ncolors);
offset = 14 + 40 + (bpp <= 8 ? (ncolors == 0 ? (1 << bpp) : ncolors) * 4 : 0);
Stream_Free(s, FALSE);
@@ -949,6 +955,7 @@ static void xf_cliprdr_process_dib(clipboardContext* cb, BYTE* data, int size)
cb->data = Stream_Buffer(s);
cb->data_length = Stream_GetPosition(s);
Stream_Free(s, FALSE);
+ return TRUE;
}
static void xf_cliprdr_process_html(clipboardContext* cb, BYTE* data, int size)
diff --git a/libfreerdp/core/fastpath.c b/libfreerdp/core/fastpath.c
index 8448160..dcc7117 100644
--- a/libfreerdp/core/fastpath.c
+++ b/libfreerdp/core/fastpath.c
@@ -254,7 +254,7 @@ static int fastpath_recv_update(rdpFastPath* fastpath, BYTE updateCode, UINT32 s
break;
case FASTPATH_UPDATETYPE_COLOR:
- if (!update_read_pointer_color(s, &pointer->pointer_color))
+ if (!update_read_pointer_color(s, &pointer->pointer_color, 24))
return -1;
IFCALL(pointer->PointerColor, context, &pointer->pointer_color);
break;
diff --git a/libfreerdp/core/orders.c b/libfreerdp/core/orders.c
index e5cc520..f22407f 100644
--- a/libfreerdp/core/orders.c
+++ b/libfreerdp/core/orders.c
@@ -1830,6 +1830,11 @@ BOOL update_read_cache_bitmap_order(wStream* s, CACHE_BITMAP_ORDER* cache_bitmap
Stream_Read_UINT8(s, cache_bitmap->bitmapWidth); /* bitmapWidth (1 byte) */
Stream_Read_UINT8(s, cache_bitmap->bitmapHeight); /* bitmapHeight (1 byte) */
Stream_Read_UINT8(s, cache_bitmap->bitmapBpp); /* bitmapBpp (1 byte) */
+ if ((cache_bitmap->bitmapBpp < 1) || (cache_bitmap->bitmapBpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bitmap bpp %d\n", __FUNCTION__, cache_bitmap->bitmapBpp);
+ return FALSE;
+ }
Stream_Read_UINT16(s, cache_bitmap->bitmapLength); /* bitmapLength (2 bytes) */
Stream_Read_UINT16(s, cache_bitmap->cacheIndex); /* cacheIndex (2 bytes) */
@@ -2068,6 +2073,11 @@ BOOL update_read_cache_bitmap_v3_order(wStream* s, CACHE_BITMAP_V3_ORDER* cache_
bitmapData = &cache_bitmap_v3->bitmapData;
Stream_Read_UINT8(s, bitmapData->bpp);
+ if ((bitmapData->bpp < 1) || (bitmapData->bpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bpp value %d", __FUNCTION__, bitmapData->bpp);
+ return FALSE;
+ }
Stream_Seek_UINT8(s); /* reserved1 (1 byte) */
Stream_Seek_UINT8(s); /* reserved2 (1 byte) */
Stream_Read_UINT8(s, bitmapData->codecID); /* codecID (1 byte) */
@@ -2672,6 +2682,11 @@ BOOL update_read_create_nine_grid_bitmap_order(wStream* s, CREATE_NINE_GRID_BITM
return FALSE;
Stream_Read_UINT8(s, create_nine_grid_bitmap->bitmapBpp); /* bitmapBpp (1 byte) */
+ if ((create_nine_grid_bitmap->bitmapBpp < 1) || (create_nine_grid_bitmap->bitmapBpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bpp value %d", __FUNCTION__, create_nine_grid_bitmap->bitmapBpp);
+ return FALSE;
+ }
Stream_Read_UINT16(s, create_nine_grid_bitmap->bitmapId); /* bitmapId (2 bytes) */
nineGridInfo = &(create_nine_grid_bitmap->nineGridInfo);
@@ -2707,6 +2722,12 @@ BOOL update_read_stream_bitmap_first_order(wStream* s, STREAM_BITMAP_FIRST_ORDER
Stream_Read_UINT8(s, stream_bitmap_first->bitmapFlags); /* bitmapFlags (1 byte) */
Stream_Read_UINT8(s, stream_bitmap_first->bitmapBpp); /* bitmapBpp (1 byte) */
+ if ((stream_bitmap_first->bitmapBpp < 1) || (stream_bitmap_first->bitmapBpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bpp value %d", __FUNCTION__, stream_bitmap_first->bitmapBpp);
+ return FALSE;
+ }
+
Stream_Read_UINT16(s, stream_bitmap_first->bitmapType); /* bitmapType (2 bytes) */
Stream_Read_UINT16(s, stream_bitmap_first->bitmapWidth); /* bitmapWidth (2 bytes) */
Stream_Read_UINT16(s, stream_bitmap_first->bitmapHeight); /* bitmapHeigth (2 bytes) */
diff --git a/libfreerdp/core/surface.c b/libfreerdp/core/surface.c
index 7d0fb22..992a3dd 100644
--- a/libfreerdp/core/surface.c
+++ b/libfreerdp/core/surface.c
@@ -38,6 +38,12 @@ static int update_recv_surfcmd_surface_bits(rdpUpdate* update, wStream* s, UINT3
Stream_Read_UINT16(s, cmd->destRight);
Stream_Read_UINT16(s, cmd->destBottom);
Stream_Read_UINT8(s, cmd->bpp);
+ if ((cmd->bpp < 1) || (cmd->bpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bpp value %d", __FUNCTION__, cmd->bpp);
+ return FALSE;
+ }
+
Stream_Seek(s, 2); /* reserved1, reserved2 */
Stream_Read_UINT8(s, cmd->codecID);
Stream_Read_UINT16(s, cmd->width);
diff --git a/libfreerdp/core/update.c b/libfreerdp/core/update.c
index c4eaede..27c36e3 100644
--- a/libfreerdp/core/update.c
+++ b/libfreerdp/core/update.c
@@ -219,16 +219,32 @@ BOOL update_read_pointer_system(wStream* s, POINTER_SYSTEM_UPDATE* pointer_syste
return TRUE;
}
-BOOL update_read_pointer_color(wStream* s, POINTER_COLOR_UPDATE* pointer_color)
+BOOL update_read_pointer_color(wStream* s, POINTER_COLOR_UPDATE* pointer_color, int xorBpp)
{
+ BYTE *newMask;
+ int scanlineSize;
+
if (Stream_GetRemainingLength(s) < 14)
return FALSE;
Stream_Read_UINT16(s, pointer_color->cacheIndex); /* cacheIndex (2 bytes) */
Stream_Read_UINT16(s, pointer_color->xPos); /* xPos (2 bytes) */
Stream_Read_UINT16(s, pointer_color->yPos); /* yPos (2 bytes) */
+
+ /**
+ * As stated in 2.2.9.1.1.4.4 Color Pointer Update:
+ * The maximum allowed pointer width/height is 96 pixels if the client indicated support
+ * for large pointers by setting the LARGE_POINTER_FLAG (0x00000001) in the Large
+ * Pointer Capability Set (section 2.2.7.2.7). If the LARGE_POINTER_FLAG was not
+ * set, the maximum allowed pointer width/height is 32 pixels.
+ *
+ * So we check for a maximum of 96 for CVE-2014-0250.
+ */
Stream_Read_UINT16(s, pointer_color->width); /* width (2 bytes) */
Stream_Read_UINT16(s, pointer_color->height); /* height (2 bytes) */
+ if ((pointer_color->width > 96) || (pointer_color->height > 96))
+ return FALSE;
+
Stream_Read_UINT16(s, pointer_color->lengthAndMask); /* lengthAndMask (2 bytes) */
Stream_Read_UINT16(s, pointer_color->lengthXorMask); /* lengthXorMask (2 bytes) */
@@ -245,26 +261,65 @@ BOOL update_read_pointer_color(wStream* s, POINTER_COLOR_UPDATE* pointer_color)
if (pointer_color->lengthXorMask > 0)
{
+ /**
+ * Spec states that:
+ *
+ * xorMaskData (variable): A variable-length array of bytes. Contains the 24-bpp, bottom-up
+ * XOR mask scan-line data. The XOR mask is padded to a 2-byte boundary for each encoded
+ * scan-line. For example, if a 3x3 pixel cursor is being sent, then each scan-line will consume 10
+ * bytes (3 pixels per scan-line multiplied by 3 bytes per pixel, rounded up to the next even
+ * number of bytes).
+ *
+ * In fact instead of 24-bpp, the bpp parameter is given by the containing packet.
+ */
if (Stream_GetRemainingLength(s) < pointer_color->lengthXorMask)
return FALSE;
- if (!pointer_color->xorMaskData)
- pointer_color->xorMaskData = malloc(pointer_color->lengthXorMask);
- else
- pointer_color->xorMaskData = realloc(pointer_color->xorMaskData, pointer_color->lengthXorMask);
+ scanlineSize = (7 + xorBpp * pointer_color->width) / 8;
+ scanlineSize = ((scanlineSize + 1) / 2) * 2;
+ if (scanlineSize * pointer_color->height != pointer_color->lengthXorMask)
+ {
+ fprintf(stderr, "%s: invalid lengthXorMask: width=%d height=%d, %d instead of %d\n", __FUNCTION__,
+ pointer_color->width, pointer_color->height,
+ pointer_color->lengthXorMask, scanlineSize * pointer_color->height);
+ return FALSE;
+ }
+
+ newMask = realloc(pointer_color->xorMaskData, pointer_color->lengthXorMask);
+ if (!newMask)
+ return FALSE;
+
+ pointer_color->xorMaskData = newMask;
Stream_Read(s, pointer_color->xorMaskData, pointer_color->lengthXorMask);
}
if (pointer_color->lengthAndMask > 0)
{
+ /**
+ * andMaskData (variable): A variable-length array of bytes. Contains the 1-bpp, bottom-up
+ * AND mask scan-line data. The AND mask is padded to a 2-byte boundary for each encoded
+ * scan-line. For example, if a 7x7 pixel cursor is being sent, then each scan-line will consume 2
+ * bytes (7 pixels per scan-line multiplied by 1 bpp, rounded up to the next even number of
+ * bytes).
+ */
if (Stream_GetRemainingLength(s) < pointer_color->lengthAndMask)
return FALSE;
- if (!pointer_color->andMaskData)
- pointer_color->andMaskData = malloc(pointer_color->lengthAndMask);
- else
- pointer_color->andMaskData = realloc(pointer_color->andMaskData, pointer_color->lengthAndMask);
+ scanlineSize = ((7 + pointer_color->width) / 8);
+ scanlineSize = ((1 + scanlineSize) / 2) * 2;
+ if (scanlineSize * pointer_color->height != pointer_color->lengthAndMask)
+ {
+ fprintf(stderr, "%s: invalid lengthAndMask: %d instead of %d\n", __FUNCTION__,
+ pointer_color->lengthAndMask, scanlineSize * pointer_color->height);
+ return FALSE;
+ }
+
+ newMask = realloc(pointer_color->andMaskData, pointer_color->lengthAndMask);
+ if (!newMask)
+ return FALSE;
+
+ pointer_color->andMaskData = newMask;
Stream_Read(s, pointer_color->andMaskData, pointer_color->lengthAndMask);
}
@@ -281,7 +336,12 @@ BOOL update_read_pointer_new(wStream* s, POINTER_NEW_UPDATE* pointer_new)
return FALSE;
Stream_Read_UINT16(s, pointer_new->xorBpp); /* xorBpp (2 bytes) */
- return update_read_pointer_color(s, &pointer_new->colorPtrAttr); /* colorPtrAttr */
+ if ((pointer_new->xorBpp < 1) || (pointer_new->xorBpp > 32))
+ {
+ fprintf(stderr, "%s: invalid xorBpp %d\n", __FUNCTION__, pointer_new->xorBpp);
+ return FALSE;
+ }
+ return update_read_pointer_color(s, &pointer_new->colorPtrAttr, pointer_new->xorBpp); /* colorPtrAttr */
}
BOOL update_read_pointer_cached(wStream* s, POINTER_CACHED_UPDATE* pointer_cached)
@@ -320,7 +380,7 @@ BOOL update_recv_pointer(rdpUpdate* update, wStream* s)
break;
case PTR_MSG_TYPE_COLOR:
- if (!update_read_pointer_color(s, &pointer->pointer_color))
+ if (!update_read_pointer_color(s, &pointer->pointer_color, 24))
return FALSE;
IFCALL(pointer->PointerColor, context, &pointer->pointer_color);
break;
diff --git a/libfreerdp/core/update.h b/libfreerdp/core/update.h
index c3088f2..d6c2d59 100644
--- a/libfreerdp/core/update.h
+++ b/libfreerdp/core/update.h
@@ -53,7 +53,7 @@ BOOL update_recv(rdpUpdate* update, wStream* s);
BOOL update_read_pointer_position(wStream* s, POINTER_POSITION_UPDATE* pointer_position);
BOOL update_read_pointer_system(wStream* s, POINTER_SYSTEM_UPDATE* pointer_system);
-BOOL update_read_pointer_color(wStream* s, POINTER_COLOR_UPDATE* pointer_color);
+BOOL update_read_pointer_color(wStream* s, POINTER_COLOR_UPDATE* pointer_color, int xorBpp);
BOOL update_read_pointer_new(wStream* s, POINTER_NEW_UPDATE* pointer_new);
BOOL update_read_pointer_cached(wStream* s, POINTER_CACHED_UPDATE* pointer_cached);
diff --git a/libfreerdp/core/window.c b/libfreerdp/core/window.c
index 7422f5b..c10fa33 100644
--- a/libfreerdp/core/window.c
+++ b/libfreerdp/core/window.c
@@ -35,6 +35,11 @@ BOOL update_read_icon_info(wStream* s, ICON_INFO* icon_info)
Stream_Read_UINT16(s, icon_info->cacheEntry); /* cacheEntry (2 bytes) */
Stream_Read_UINT8(s, icon_info->cacheId); /* cacheId (1 byte) */
Stream_Read_UINT8(s, icon_info->bpp); /* bpp (1 byte) */
+ if ((icon_info->bpp < 1) || (icon_info->bpp > 32))
+ {
+ fprintf(stderr, "%s: invalid bpp %d\n", __FUNCTION__, icon_info->bpp);
+ return FALSE;
+ }
Stream_Read_UINT16(s, icon_info->width); /* width (2 bytes) */
Stream_Read_UINT16(s, icon_info->height); /* height (2 bytes) */
--
1.9.3