| Message ID | 20241119131011.105359-2-biju.das.jz@bp.renesas.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | drm: adv7511: ADV7535 fixes | expand |
Hi Biju, Thank you for the patch. On Tue, Nov 19, 2024 at 01:10:03PM +0000, Biju Das wrote: > The host_node pointer was assigned and freed in adv7533_parse_dt(), and > later, adv7533_attach_dsi() uses the same. Fix this use-after-free issue > by dropping of_node_put() in adv7533_parse_dt() and calling of_node_put() > in error path of probe() and also in the remove(). > > Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device") > Cc: stable@vger.kernel.org > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> > --- > Changes in v5: > - Updated commit description. > - restored host_node in struct adv7511. > - Dropped of_node_put() in adv7533_parse_dt() and calling of_node_put() > in error path of probe() and also in the remove(). > Changes in v4: > - Updated commit description. > - Dropped host_node from struct adv7511 and instead used a local pointer > in probe(). Also freeing of host_node pointer after use is done in > probe(). > Changes in v3: > - Replace __free construct with readable of_node_put(). > Changes in v2: > - Added the tag "Cc: stable@vger.kernel.org" in the sign-off area. > - Dropped Archit Taneja invalid Mail address > --- > drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 5 +++++ > drivers/gpu/drm/bridge/adv7511/adv7533.c | 2 -- > 2 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > index eb5919b38263..6cfdda04f52f 100644 > --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > @@ -1363,6 +1363,8 @@ static int adv7511_probe(struct i2c_client *i2c) > i2c_unregister_device(adv7511->i2c_edid); > uninit_regulators: > adv7511_uninit_regulators(adv7511); > + if (adv7511->host_node) > + of_node_put(adv7511->host_node); This won't be called when adv7511_init_regulators() fails as the driver returns directly then, leaking the reference. You need a new error label and a goto for that error path. In the future, when touching error handling, please try to check existing error paths and verify they're still right. > > return ret; > } > @@ -1371,6 +1373,9 @@ static void adv7511_remove(struct i2c_client *i2c) > { > struct adv7511 *adv7511 = i2c_get_clientdata(i2c); > > + if (adv7511->host_node) > + of_node_put(adv7511->host_node); > + > adv7511_uninit_regulators(adv7511); > > drm_bridge_remove(&adv7511->bridge); > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7533.c b/drivers/gpu/drm/bridge/adv7511/adv7533.c > index 4481489aaf5e..5f195e91b3e6 100644 > --- a/drivers/gpu/drm/bridge/adv7511/adv7533.c > +++ b/drivers/gpu/drm/bridge/adv7511/adv7533.c > @@ -181,8 +181,6 @@ int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv) > if (!adv->host_node) > return -ENODEV; > > - of_node_put(adv->host_node); > - > adv->use_timing_gen = !of_property_read_bool(np, > "adi,disable-timing-generator"); >
Hi Laurent, > -----Original Message----- > From: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Sent: 19 November 2024 16:28 > Subject: Re: [PATCH v5 1/3] drm: adv7511: Fix use-after-free in adv7533_attach_dsi() > > Hi Biju, > > Thank you for the patch. > > On Tue, Nov 19, 2024 at 01:10:03PM +0000, Biju Das wrote: > > The host_node pointer was assigned and freed in adv7533_parse_dt(), > > and later, adv7533_attach_dsi() uses the same. Fix this use-after-free > > issue by dropping of_node_put() in adv7533_parse_dt() and calling > > of_node_put() in error path of probe() and also in the remove(). > > > > Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device") > > Cc: stable@vger.kernel.org > > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> > > --- > > Changes in v5: > > - Updated commit description. > > - restored host_node in struct adv7511. > > - Dropped of_node_put() in adv7533_parse_dt() and calling of_node_put() > > in error path of probe() and also in the remove(). > > Changes in v4: > > - Updated commit description. > > - Dropped host_node from struct adv7511 and instead used a local pointer > > in probe(). Also freeing of host_node pointer after use is done in > > probe(). > > Changes in v3: > > - Replace __free construct with readable of_node_put(). > > Changes in v2: > > - Added the tag "Cc: stable@vger.kernel.org" in the sign-off area. > > - Dropped Archit Taneja invalid Mail address > > --- > > drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 5 +++++ > > drivers/gpu/drm/bridge/adv7511/adv7533.c | 2 -- > > 2 files changed, 5 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > > b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > > index eb5919b38263..6cfdda04f52f 100644 > > --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > > +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > > @@ -1363,6 +1363,8 @@ static int adv7511_probe(struct i2c_client *i2c) > > i2c_unregister_device(adv7511->i2c_edid); > > uninit_regulators: > > adv7511_uninit_regulators(adv7511); > > + if (adv7511->host_node) > > + of_node_put(adv7511->host_node); > > This won't be called when adv7511_init_regulators() fails as the driver returns directly then, leaking > the reference. You need a new error label and a goto for that error path. Oops missed again. > > In the future, when touching error handling, please try to check existing error paths and verify > they're still right. Yes, will take care next time. Cheers, Biju > > > > > return ret; > > } > > @@ -1371,6 +1373,9 @@ static void adv7511_remove(struct i2c_client > > *i2c) { > > struct adv7511 *adv7511 = i2c_get_clientdata(i2c); > > > > + if (adv7511->host_node) > > + of_node_put(adv7511->host_node); > > + > > adv7511_uninit_regulators(adv7511); > > > > drm_bridge_remove(&adv7511->bridge); > > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7533.c > > b/drivers/gpu/drm/bridge/adv7511/adv7533.c > > index 4481489aaf5e..5f195e91b3e6 100644 > > --- a/drivers/gpu/drm/bridge/adv7511/adv7533.c > > +++ b/drivers/gpu/drm/bridge/adv7511/adv7533.c > > @@ -181,8 +181,6 @@ int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv) > > if (!adv->host_node) > > return -ENODEV; > > > > - of_node_put(adv->host_node); > > - > > adv->use_timing_gen = !of_property_read_bool(np, > > "adi,disable-timing-generator"); > > > > -- > Regards, > > Laurent Pinchart
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index eb5919b38263..6cfdda04f52f 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -1363,6 +1363,8 @@ static int adv7511_probe(struct i2c_client *i2c) i2c_unregister_device(adv7511->i2c_edid); uninit_regulators: adv7511_uninit_regulators(adv7511); + if (adv7511->host_node) + of_node_put(adv7511->host_node); return ret; } @@ -1371,6 +1373,9 @@ static void adv7511_remove(struct i2c_client *i2c) { struct adv7511 *adv7511 = i2c_get_clientdata(i2c); + if (adv7511->host_node) + of_node_put(adv7511->host_node); + adv7511_uninit_regulators(adv7511); drm_bridge_remove(&adv7511->bridge); diff --git a/drivers/gpu/drm/bridge/adv7511/adv7533.c b/drivers/gpu/drm/bridge/adv7511/adv7533.c index 4481489aaf5e..5f195e91b3e6 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7533.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7533.c @@ -181,8 +181,6 @@ int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv) if (!adv->host_node) return -ENODEV; - of_node_put(adv->host_node); - adv->use_timing_gen = !of_property_read_bool(np, "adi,disable-timing-generator");
The host_node pointer was assigned and freed in adv7533_parse_dt(), and later, adv7533_attach_dsi() uses the same. Fix this use-after-free issue by dropping of_node_put() in adv7533_parse_dt() and calling of_node_put() in error path of probe() and also in the remove(). Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device") Cc: stable@vger.kernel.org Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- Changes in v5: - Updated commit description. - restored host_node in struct adv7511. - Dropped of_node_put() in adv7533_parse_dt() and calling of_node_put() in error path of probe() and also in the remove(). Changes in v4: - Updated commit description. - Dropped host_node from struct adv7511 and instead used a local pointer in probe(). Also freeing of host_node pointer after use is done in probe(). Changes in v3: - Replace __free construct with readable of_node_put(). Changes in v2: - Added the tag "Cc: stable@vger.kernel.org" in the sign-off area. - Dropped Archit Taneja invalid Mail address --- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 5 +++++ drivers/gpu/drm/bridge/adv7511/adv7533.c | 2 -- 2 files changed, 5 insertions(+), 2 deletions(-)