[PATCH 5.1 008/155] drm/msm: correct attempted NULL pointer dereference in debugfs

Greg Kroah-Hartman
2019-06-13T15:55:34Z

[ Upstream commit 90f94660e53189755676543954101de78c26253b ]

msm_gem_describe() would attempt to dereference a NULL pointer via the
address space pointer when no IOMMU is present. Correct this by adding
the appropriate check.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Fixes: 575f0485508b ("drm/msm: Clean up and enhance the output of the 'gem' debugfs node")
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190513234105.7531-2-masneyb@onstation.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/msm/msm_gem.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 18ca651ab942..23de4d1b7b1a 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -805,7 +805,8 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
seq_puts(m, " vmas:");

list_for_each_entry(vma, &msm_obj->vmas, list)
- seq_printf(m, " [%s: %08llx,%s,inuse=%d]", vma->aspace->name,
+ seq_printf(m, " [%s: %08llx,%s,inuse=%d]",
+ vma->aspace != NULL ? vma->aspace->name : NULL,
vma->iova, vma->mapped ? "mapped" : "unmapped",
vma->inuse);

--
2.20.1