On Tue, Jul 20, 2010 at 5:07 PM, Alexander Y. Fomichev <git.user@xxxxxxxxx> wrote: > On Wed, Jul 21, 2010 at 1:00 AM, Alex Deucher <alexdeucher@xxxxxxxxx> wrote: >> On Tue, Jul 20, 2010 at 4:13 PM, Alexander Y. Fomichev >> <git.user@xxxxxxxxx> wrote: >>> On Tue, Jul 20, 2010 at 9:37 PM, Alex Deucher <alexdeucher@xxxxxxxxx> wrote: >>>> On Mon, Jul 19, 2010 at 5:42 PM, Alexander Y. Fomichev >>>> <git.user@xxxxxxxxx> 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. yeah, either way. You just need to return an error in r600_prepare_blit_copy. Alex > >> Alex >> >>> >>> -- >>> Best regards. >>> Alexander Y. Fomichev <git.user@xxxxxxxxx> >>> >> > > > > -- > Best regards. > Alexander Y. Fomichev <git.user@xxxxxxxxx> > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
