From: Nick Piggin <npiggin@suse.de>
Subject: insufficient range checks of certain fault handlers (CVE-2008-0007)
References: 353207
Patch-upstream: not yet

This patch is a security fix for CVE-2008-0007. See bugzilla for details.

---
Index: linux-2.6.22/drivers/char/drm/drm_vm.c
===================================================================
--- linux-2.6.22.orig/drivers/char/drm/drm_vm.c
+++ linux-2.6.22/drivers/char/drm/drm_vm.c
@@ -520,6 +520,7 @@ static int drm_mmap_dma(struct file *fil
 	vma->vm_ops = &drm_vm_dma_ops;
 
 	vma->vm_flags |= VM_RESERVED;	/* Don't swap */
+	vma->vm_flags |= VM_DONTEXPAND;
 
 	vma->vm_file = filp;	/* Needed for drm_vm_open() */
 	drm_vm_open_locked(vma);
@@ -669,6 +670,7 @@ static int drm_mmap_locked(struct file *
 		return -EINVAL;	/* This should never happen. */
 	}
 	vma->vm_flags |= VM_RESERVED;	/* Don't swap */
+	vma->vm_flags |= VM_DONTEXPAND;
 
 	vma->vm_file = filp;	/* Needed for drm_vm_open() */
 	drm_vm_open_locked(vma);
Index: linux-2.6.22/kernel/relay.c
===================================================================
--- linux-2.6.22.orig/kernel/relay.c
+++ linux-2.6.22/kernel/relay.c
@@ -91,6 +91,7 @@ int relay_mmap_buf(struct rchan_buf *buf
 		return -EINVAL;
 
 	vma->vm_ops = &relay_file_mmap_ops;
+	vma->vm_flags |= VM_DONTEXPAND;
 	vma->vm_private_data = buf;
 	buf->chan->cb->buf_mapped(buf, filp);
 
Index: linux-2.6.22/mm/mmap.c
===================================================================
--- linux-2.6.22.orig/mm/mmap.c
+++ linux-2.6.22/mm/mmap.c
@@ -2157,7 +2157,7 @@ int install_special_mapping(struct mm_st
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
 
-	vma->vm_flags = vm_flags | mm->def_flags;
+	vma->vm_flags = vm_flags | mm->def_flags | VM_DONTEXPAND;
 	vma->vm_page_prot = protection_map[vma->vm_flags & 7];
 
 	vma->vm_ops = &special_mapping_vmops;
Index: linux-2.6.22/sound/oss/via82cxxx_audio.c
===================================================================
--- linux-2.6.22.orig/sound/oss/via82cxxx_audio.c
+++ linux-2.6.22/sound/oss/via82cxxx_audio.c
@@ -2104,6 +2104,7 @@ static struct page * via_mm_nopage (stru
 {
 	struct via_info *card = vma->vm_private_data;
 	struct via_channel *chan = &card->ch_out;
+	unsigned long max_bufs;
 	struct page *dmapage;
 	unsigned long pgoff;
 	int rd, wr;
@@ -2127,14 +2128,11 @@ static struct page * via_mm_nopage (stru
 	rd = card->ch_in.is_mapped;
 	wr = card->ch_out.is_mapped;
 
-#ifndef VIA_NDEBUG
-	{
-	unsigned long max_bufs = chan->frag_number;
-	if (rd && wr) max_bufs *= 2;
-	/* via_dsp_mmap() should ensure this */
-	assert (pgoff < max_bufs);
-	}
-#endif
+	max_bufs = chan->frag_number;
+	if (rd && wr)
+		max_bufs *= 2;
+	if (pgoff >= max_bufs)
+		return NOPAGE_SIGBUS;
 
 	/* if full-duplex (read+write) and we have two sets of bufs,
 	 * then the playback buffers come first, sez soundcard.c */
Index: linux-2.6.22/sound/usb/usx2y/usX2Yhwdep.c
===================================================================
--- linux-2.6.22.orig/sound/usb/usx2y/usX2Yhwdep.c
+++ linux-2.6.22/sound/usb/usx2y/usX2Yhwdep.c
@@ -88,7 +88,7 @@ static int snd_us428ctls_mmap(struct snd
 		us428->us428ctls_sharedmem->CtlSnapShotLast = -2;
 	}
 	area->vm_ops = &us428ctls_vm_ops;
-	area->vm_flags |= VM_RESERVED;
+	area->vm_flags |= VM_RESERVED | VM_DONTEXPAND;
 	area->vm_private_data = hw->private_data;
 	return 0;
 }
Index: linux-2.6.22/sound/usb/usx2y/usx2yhwdeppcm.c
===================================================================
--- linux-2.6.22.orig/sound/usb/usx2y/usx2yhwdeppcm.c
+++ linux-2.6.22/sound/usb/usx2y/usx2yhwdeppcm.c
@@ -728,7 +728,7 @@ static int snd_usX2Y_hwdep_pcm_mmap(stru
 		return -ENODEV;
 	}
 	area->vm_ops = &snd_usX2Y_hwdep_pcm_vm_ops;
-	area->vm_flags |= VM_RESERVED;
+	area->vm_flags |= VM_RESERVED | VM_DONTEXPAND;
 	area->vm_private_data = hw->private_data;
 	return 0;
 }
Index: linux-2.6.22/drivers/char/mspec.c
===================================================================
--- linux-2.6.22.orig/drivers/char/mspec.c
+++ linux-2.6.22/drivers/char/mspec.c
@@ -265,7 +265,7 @@ mspec_mmap(struct file *file, struct vm_
 	vdata->refcnt = ATOMIC_INIT(1);
 	vma->vm_private_data = vdata;
 
-	vma->vm_flags |= (VM_IO | VM_LOCKED | VM_RESERVED | VM_PFNMAP);
+	vma->vm_flags |= (VM_IO | VM_LOCKED | VM_RESERVED | VM_PFNMAP | VM_DONTEXPAND);
 	if (vdata->type == MSPEC_FETCHOP || vdata->type == MSPEC_UNCACHED)
 		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 	vma->vm_ops = &mspec_vm_ops;
Index: linux-2.6.22/sound/oss/emu10k1/audio.c
===================================================================
--- linux-2.6.22.orig/sound/oss/emu10k1/audio.c
+++ linux-2.6.22/sound/oss/emu10k1/audio.c
@@ -1111,7 +1111,7 @@ static int emu10k1_audio_mmap(struct fil
 	if (pgoffset + n_pages > max_pages)
 		return -EINVAL;
 
-	vma->vm_flags |= VM_RESERVED;
+	vma->vm_flags |= VM_RESERVED | VM_DONTEXPAND;
 	vma->vm_ops = &emu10k1_mm_ops;
 	vma->vm_private_data = wave_dev;
 	return 0;