Messages in this thread | | | Date | Wed, 18 May 2016 22:51:49 +0200 | Subject | Re: [PATCH 1/1] drm/gma500: mdfld: avoid possible null pointer dereference | From | Patrik Jakobsson <> |
| |
On Wed, May 18, 2016 at 10:31 PM, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: > Only dereference sender after checking if sender is NULL.
Hi Heinrich
I think we had a patch that did something similar a while ago. Don't remember what happened to it. We do check for !sender right before calling this function (at only one call-site) so it cannot be NULL at this point. I would be ok with your change if you also remove the extra checks in mdfld_dsi_read_mcs(). That way we don't double check and we check at the point where it actually matters.
Thanks Patrik
> > Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> > --- > drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c b/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c > index 1616af2..c50534c 100644 > --- a/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c > +++ b/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c > @@ -520,7 +520,7 @@ static int __read_panel_data(struct mdfld_dsi_pkg_sender *sender, u8 data_type, > u8 *data, u16 len, u32 *data_out, u16 len_out, bool hs) > { > unsigned long flags; > - struct drm_device *dev = sender->dev; > + struct drm_device *dev; > int i; > u32 gen_data_reg; > int retry = MDFLD_DSI_READ_MAX_COUNT; > @@ -530,6 +530,8 @@ static int __read_panel_data(struct mdfld_dsi_pkg_sender *sender, u8 data_type, > return -EINVAL; > } > > + dev = sender->dev; > + > /** > * do reading. > * 0) send out generic read request > -- > 2.1.4 >
| |