Le 08/09/2025 à 23:26, Dmitry Baryshkov a écrit :
On Mon, Sep 08, 2025 at 11:09:07PM +0200, Christophe JAILLET wrote:
Le 19/08/2025 à 22:32, Dmitry Baryshkov a écrit :
Use drmm_plain_encoder_alloc() to allocate simple encoder and
drmm_writeback_connector_init() in order to initialize writeback
connector instance.
Reviewed-by: Louis Chauvet <louis.chauvet-LDxbnhwyfcJBDgjK7y7TUQ-XMD5yJDbdMReXY1tMh2IBg@xxxxxxxxxxxxxxxx>
Reviewed-by: Suraj Kandpal <suraj.kandpal-ral2JQCrhuEAvxtiuMwx3w-XMD5yJDbdMReXY1tMh2IBg@xxxxxxxxxxxxxxxx>
Reviewed-by: Jessica Zhang <jessica.zhang-5oFBVzJwu8Ry9aJCnZT0Uw-XMD5yJDbdMReXY1tMh2IBg@xxxxxxxxxxxxxxxx>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov-5oFBVzJwu8Ry9aJCnZT0Uw-XMD5yJDbdMReXY1tMh2IBg@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
index 8ff496082902b1ee713e806140f39b4730ed256a..cd73468e369a93c50303db2a7d4499bcb17be5d1 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
@@ -80,7 +80,6 @@ static int dpu_wb_conn_atomic_check(struct drm_connector *connector,
static const struct drm_connector_funcs dpu_wb_conn_funcs = {
.reset = drm_atomic_helper_connector_reset,
.fill_modes = drm_helper_probe_single_connector_modes,
- .destroy = drm_connector_cleanup,
.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};
@@ -131,12 +130,9 @@ int dpu_writeback_init(struct drm_device *dev, struct drm_encoder *enc,
drm_connector_helper_add(&dpu_wb_conn->base.base, &dpu_wb_conn_helper_funcs);
- /* DPU initializes the encoder and sets it up completely for writeback
- * cases and hence should use the new API drm_writeback_connector_init_with_encoder
- * to initialize the writeback connector
- */
- rc = drm_writeback_connector_init_with_encoder(dev, &dpu_wb_conn->base, enc,
- &dpu_wb_conn_funcs, format_list, num_formats);
+ rc = drmm_writeback_connector_init(dev, &dpu_wb_conn->base,
+ &dpu_wb_conn_funcs, enc,
+ format_list, num_formats);
if (!rc)
dpu_wb_conn->wb_enc = enc;
dpu_wb_conn is allocated a few lines above using devm_kzalloc().
That's a valid point, thanks!
I've not analyzed in details all the patches of the serie, but at least
patch 2/8 and 6/8 seems to have the same pattern.
CJ
Based on [1], mixing devm_ and drmm_ is not safe and can lead to a uaf.
Is it correct here?
If the explanation at [1] is correct, then &dpu_wb_conn->base would point to
some released memory, IIUC.
just my 2c.
CJ
[1]: https://web.git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/gpu/drm/xe/xe_hwmon.c?id=3a13c2de442d6bfaef9c102cd1092e6cae22b753
