vm audit: add VM_DONTEXPAND to mmap for drivers that need it

Drivers that register a ->fault handler, but do not range-check the
offset argument, must set VM_DONTEXPAND in the vm_flags in order to
prevent an expanding mremap from overflowing the resource.

I've audited the tree and attempted to fix these problems (usually by
adding VM_DONTEXPAND where it is not obvious).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 2 insertions, 2 deletions

diff --git a/sound/usb/usx2y/usX2Yhwdep.c b/sound/usb/usx2y/usX2Yhwdep.c
index 6495534e5bf6..1558a5c4094f 100644
--- a/sound/usb/usx2y/usX2Yhwdep.c
+++ b/sound/usb/usx2y/usX2Yhwdep.c
@@ -84,7 +84,7 @@ static int snd_us428ctls_mmap(struct snd_hwdep * hw, struct file *filp, struct v
                 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;
 }
diff --git a/sound/usb/usx2y/usx2yhwdeppcm.c b/sound/usb/usx2y/usx2yhwdeppcm.c
index 800b5cecfc80..117946f2debb 100644
--- a/sound/usb/usx2y/usx2yhwdeppcm.c
+++ b/sound/usb/usx2y/usx2yhwdeppcm.c
@@ -722,7 +722,7 @@ static int snd_usX2Y_hwdep_pcm_mmap(struct snd_hwdep * hw, struct file *filp, st
                 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;
 }