On Thu, Jan 11, 2018 at 1:54 AM, Jiri Kosina <jikos@xxxxxxxxxx> wrote: > On Tue, 9 Jan 2018, Josh Poimboeuf wrote: > >> On Tue, Jan 09, 2018 at 11:44:05AM -0800, Dan Williams wrote: >> > On Tue, Jan 9, 2018 at 11:34 AM, Jiri Kosina <jikos@xxxxxxxxxx> wrote: >> > > On Fri, 5 Jan 2018, Dan Williams wrote: >> > > >> > > [ ... snip ... ] >> > >> Andi Kleen (1): >> > >> x86, barrier: stop speculation for failed access_ok >> > >> >> > >> Dan Williams (13): >> > >> x86: implement nospec_barrier() >> > >> [media] uvcvideo: prevent bounds-check bypass via speculative execution >> > >> carl9170: prevent bounds-check bypass via speculative execution >> > >> p54: prevent bounds-check bypass via speculative execution >> > >> qla2xxx: prevent bounds-check bypass via speculative execution >> > >> cw1200: prevent bounds-check bypass via speculative execution >> > >> Thermal/int340x: prevent bounds-check bypass via speculative execution >> > >> ipv6: prevent bounds-check bypass via speculative execution >> > >> ipv4: prevent bounds-check bypass via speculative execution >> > >> vfs, fdtable: prevent bounds-check bypass via speculative execution >> > >> net: mpls: prevent bounds-check bypass via speculative execution >> > >> udf: prevent bounds-check bypass via speculative execution >> > >> userns: prevent bounds-check bypass via speculative execution >> > >> >> > >> Mark Rutland (4): >> > >> asm-generic/barrier: add generic nospec helpers >> > >> Documentation: document nospec helpers >> > >> arm64: implement nospec_ptr() >> > >> arm: implement nospec_ptr() >> > > >> > > So considering the recent publication of [1], how come we all of a sudden >> > > don't need the barriers in ___bpf_prog_run(), namely for LD_IMM_DW and >> > > LDX_MEM_##SIZEOP, and something comparable for eBPF JIT? >> > > >> > > Is this going to be handled in eBPF in some other way? >> > > >> > > Without that in place, and considering Jann Horn's paper, it would seem >> > > like PTI doesn't really lock it down fully, right? >> > >> > Here is the latest (v3) bpf fix: >> > >> > https://patchwork.ozlabs.org/patch/856645/ >> > >> > I currently have v2 on my 'nospec' branch and will move that to v3 for >> > the next update, unless it goes upstream before then. > > Daniel, I guess you're planning to send this still for 4.15? It's pending in the bpf.git tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=b2157399cc9 >> That patch seems specific to CONFIG_BPF_SYSCALL. Is the bpf() syscall >> the only attack vector? Or are there other ways to run bpf programs >> that we should be worried about? > > Seems like Alexei is probably the only person in the whole universe who > isn't CCed here ... let's fix that. He will be cc'd on v2 of this series which will be available later today.
