ros-perception / openslam_gmapping

218 stars 206 forks source link

Enforce check to avoid memory corruption #23

Open danieldugas opened 5 years ago

danieldugas commented 5 years ago

Ubuntu 16.04, ROS Kinetic.

gmapping kept crashing when I published high resolution laser scans, it took me a while to figure out why.

The cause of the crash was especially hard to find since memory corruption caused the program to terminate much later than where the corruption occured. Finally, we traced it down to this.

if the laserscan has more beams than LASER_MAXBEAMS, the memcpy operation here leads to memory corruption.

Of course, there is an assert a few lines above. However it did not get triggered (is NDEBUG defined somewhere?). I believe this is not specific to me, as I am using the debian distributed ros version of openslam_gmapping.

I'm convinced replacing the assert with an inexpensive if, verbose message, and exit(-1) would be one way to ensure this error does not inconvenience anymore users, though this much is up to you.

Cheers