On Fri, Sep 04, 2015 at 01:17:30PM -0700, Kees Cook wrote: > On Fri, Sep 4, 2015 at 9:04 AM, Tycho Andersen > <tycho.ander...@canonical.com> wrote: > > This commit adds a way to dump eBPF programs. The initial implementation > > doesn't support maps, and therefore only allows dumping seccomp ebpf > > programs which themselves don't currently support maps. > > > > We export the GPL bit as well as a unique ID for the program so that > > This unique ID appears to be the heap address for the prog. That's a > huge leak, and should not be done. We don't want to introduce new > kernel address leaks while we're trying to fix the remaining ones. > Shouldn't the "unique ID" be the fd itself? I imagine KCMP_FILE > could be used, for example.
No; we acquire the fd per process, so if a task installs a filter and then forks N times, we'll grab N (+1) copies of the filter from N (+1) different file descriptors. Ideally, we'd have some way to figure out that these were all the same. Some sort of prog_id is one way, although there may be others. Tycho -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
