This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.
In radeon_gem_userptr_ioctl() an MMU notifier is set up with a (tagged)
userspace pointer. The untagged address should be used so that MMU
notifiers for the untagged address get correctly matched up with the right
BO. This funcation also calls radeon_ttm_tt_pin_userptr(), which uses
provided user pointers for vma lookups, which can only by done with
untagged pointers.
This patch untags user pointers in radeon_gem_userptr_ioctl().
Reviewed-by: Khalid Aziz <khalid.a...@oracle.com>
Reviewed-by: Kees Cook <keesc...@chromium.org>
Suggested-by: Felix Kuehling <felix.kuehl...@amd.com>
Acked-by: Felix Kuehling <felix.kuehl...@amd.com>
Signed-off-by: Andrey Konovalov <andreyk...@google.com>
---
drivers/gpu/drm/radeon/radeon_gem.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c
b/drivers/gpu/drm/radeon/radeon_gem.c
index d8bc5d2dfd61..89353098b627 100644
--- a/drivers/gpu/drm/radeon/radeon_gem.c
+++ b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -296,6 +296,8 @@ int radeon_gem_userptr_ioctl(struct drm_device *dev, void
*data,
uint32_t handle;
int r;
+ args->addr = untagged_addr(args->addr);
+
if (offset_in_page(args->addr | args->size))
return -EINVAL;
--
2.22.0.709.g102302147b-goog
