On Wed, 2010-07-21 at 01:07 +0400, Alexander Y. Fomichev wrote:
On Wed, Jul 21, 2010 at 1:00 AM, Alex Deucher alexdeucher@gmail.com wrote:
On Tue, Jul 20, 2010 at 4:13 PM, Alexander Y. Fomichev git.user@gmail.com wrote:
On Tue, Jul 20, 2010 at 9:37 PM, Alex Deucher alexdeucher@gmail.com wrote:
On Mon, Jul 19, 2010 at 5:42 PM, Alexander Y. Fomichev git.user@gmail.com wrote:
This patch fix possible NULL pointer dereference when r600_prepare_blit_copy tries to fill dev_priv->blit_vb->file_priv without check of dev_priv->blit_vb. dev_priv->blit_vb should be filled by r600_nomm_get_vb but latest can fail with EAGAIN. Addresses: https://bugzilla.kernel.org/show_bug.cgi?id=16375
drivers/gpu/drm/radeon/r600_blit.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/radeon/r600_blit.c b/drivers/gpu/drm/radeon/r600_blit.c index f4fb88e..0df4a2b 100644 --- a/drivers/gpu/drm/radeon/r600_blit.c +++ b/drivers/gpu/drm/radeon/r600_blit.c @@ -541,6 +541,8 @@ r600_prepare_blit_copy(struct drm_device *dev, struct drm_file *file_priv) DRM_DEBUG("\n");
r600_nomm_get_vb(dev);
if (!dev_priv->blit_vb)return;r600_prepare_blit_copy returns an int so something like this would be better: --- a/drivers/gpu/drm/radeon/r600_blit.c +++ b/drivers/gpu/drm/radeon/r600_blit.c @@ -539,8 +539,10 @@ r600_prepare_blit_copy(struct drm_device *dev, struct drm_file *file_priv) { drm_radeon_private_t *dev_priv = dev->dev_private; DRM_DEBUG("\n");
int ret = r600_nomm_get_vb(dev);
r600_nomm_get_vb(dev);
if (ret)return ret; dev_priv->blit_vb->file_priv = file_priv;Alex
dev_priv->blit_vb->file_priv = file_priv;-- 1.7.1.1
i haven't any preferneces, the only thing is - it would be logical to have every check in common style, so other cases (r600_blit_copy, r600_blit_swap) should be fixed, nop?
Those are void functions so there's nothing to return.
i mean both of them call r600_nomm_get_vb and both of them check if (!dev_priv->blit_vb), not return value.I mean would be logical to check it the same way everytime r600_nomm_get_vb gets called.
I'm going to go with Alex's patch, as none of the other callsites return an error, and your patch doesn't return value from a function which has a int return type, causing a warning.
Dave.