Hi Shaobo, n Mon, Mar 18, 2019 at 05:01:10PM -0600, Shaobo He wrote: > Hello everyone, > > My name is Shaobo He and I am a graduate student at University of Utah. I am > using a static analysis tool to search for null pointer dereferences and > came across a potentially invalid memory access in the file > drivers/gpu/drm/i915/intel_crt.c: in function `intel_crt_detect_ddc`, > function `intel_gmbus_get_adapter` can return a NULL pointer which is if this happens we've done a terrible job on defining the platform... > dereferenced by the call to `drm_get_edid` or `intel_gmbus_is_forced_bit`. but it seems you are right... this will reach i2c_transfer in the end and it will break everything after we gave the Warning... > It seems that the return value of `intel_gmbus_get_adapter` is never > NULL-checked. If so, it would be better to replace the branch to return a > NULL pointer with something like `BUG_ON`. what about just adding if (!i2c) return false instead of BUG. We already have the WARN to debug if this case ever happens. Thanks, Rodrigo. > > Please let me know if it makes sense. I am looking forward to your reply. > > Best, > Shaobo _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
