From: Dmitry Osipenko <digetx@gmail.com>
Date: Wed, 14 Jun 2017 23:18:35 +0000 (+0300)
Subject: gpu: host1x: Forbid relocation address shifting in the firewall
X-Git-Tag: v4.14-rc1~484^2~18^2~8
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=571cbf70c117664d142b34fa2b3b915d8374a327;p=platform%2Fkernel%2Flinux-rpi.git

gpu: host1x: Forbid relocation address shifting in the firewall

Incorrectly shifted relocation address will cause a lower memory
corruption and likely a hang on a write or a read of an arbitrary data
in case of IOMMU absence. As of now, there is no known use for the
address shifting and adding a proper shifts / sizes validation is a much
more work. Let's forbid shifts in the firewall till a proper validation
is implemented.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Erik Faye-Lund <kusmabite@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
---

diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c
index 4208329..a911de6 100644
--- a/drivers/gpu/host1x/job.c
+++ b/drivers/gpu/host1x/job.c
@@ -330,6 +330,10 @@ static bool check_reloc(struct host1x_reloc *reloc, struct host1x_bo *cmdbuf,
 	if (reloc->cmdbuf.bo != cmdbuf || reloc->cmdbuf.offset != offset)
 		return false;
 
+	/* relocation shift value validation isn't implemented yet */
+	if (reloc->shift)
+		return false;
+
 	return true;
 }