On Wed, Aug 09, 2017 at 12:01:53PM -0700, Kees Cook wrote: > This series is the result of Fabricio and I going around a few times > on possible solutions for finding a way to enhance RET_KILL to kill > the process group. There's a lot of ways this could be done, but I > wanted something that felt cleanest. As it happens, Tyler's recent > patch series for logging improvement also needs to know a litte bit > more during filter runs, and the solution for both is to pass back > the matched filter. This lets us examine it here for RET_KILL and > in the future for logging changes. > > The filter passing is patch 1, the new flag for RET_KILL is patch 2. > Some test refactoring is in patch 3 for the RET_DATA ordering, and > patch 4 is the test for the new RET_KILL flag. > > One thing missing is that CRIU will likely need to be updated, since > saving/restoring seccomp filter _rules_ will not include the filter > _flags_ for a process. This can be addressed separately.
Thanks for the heads up, I suppose PTRACE_SECCOMP_GET_FLAGS similar to how PTRACE_SECCOMP_GET_FILTER works will be fine for this. One question is: would we then also need to keep track of the TSYNC flag? I don't think CRIU needs this to be correct, and we can grab the KILL_PROCESS flag from filter->kill_process, so perhaps it's moot. Anyway, happy to do this and the userspace part when this lands. Cheers, Tycho > Please take a look! > > Thanks, > > -Kees > > v3: > - adjust seccomp_run_filters() to avoid later filters from masking > kill-process RET_KILL actions (drewry) > - add test for masked RET_KILL. > > v2: > - moved kill_process bool into struct padding gap (tyhicks) > - improved comments/docs in various places for clarify (tyhicks) > - use ASSERT_TRUE() for WIFEXITED and WIFSIGNALLED (tyhicks) > - adding Reviewed-bys from tyhicks >
