Am Fr., 17. Dez. 2021 um 11:59 Uhr schrieb Lucas Stach <l.stach@xxxxxxxxxxxxxx>: > > Currently we allow rediculous ammounts of kernel memory being allocated > via the etnaviv GEM_SUBMIT ioctl, which is a pretty easy DoS vector. Put > some reasonable limits in to fix this. > > The commandstream size is limited to 64KB, which was already a soft limit > on older kernels after which the kernel only took submits on a best effort > base, so there is no userspace that tries to submit commandstreams larger > than this. Even if the whole commandstream is a single incrementing address > load, the size limit also limits the number of potential relocs and > referenced buffers to slightly under 64K, so use the same limit for those > arguments. The performance monitoring infrastructure currently supports > less than 50 performance counter signals, so limiting them to 128 on a > single submit seems like a reasonably future-proof number for now. This > number can be bumped if needed without breaking the interface. > > Cc: stable@xxxxxxxxxxxxxxx > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Reviewed-by: Christian Gmeiner <christian.gmeiner@xxxxxxxxx> -- greets -- Christian Gmeiner, MSc https://christian-gmeiner.info/privacypolicy
