Matt, On Tue, Sep 10, 2013 at 11:19:44AM +0100, Michael Cree wrote: > On Tue, Sep 10, 2013 at 10:58:12AM +0100, Will Deacon wrote: > > Vince's perf fuzzer uncovered the following issue on Alpha: > > > > Unable to handle kernel paging request at virtual address fffffbfe4e46a0e8 > > CPU 0 perf_fuzzer(1278): Oops 0 > > pc = [<fffffc000031fbc0>] ra = [<fffffc000031ff54>] ps = 0007 Not tainted > > pc is at alpha_perf_event_set_period+0x60/0xf0 > > ra is at alpha_pmu_enable+0x1a4/0x1c0 > > v0 = 0000000000000000 t0 = 00000000000fffff t1 = fffffc007b3f5800 > > t2 = fffffbff275faa94 t3 = ffffffffc9b9bd89 t4 = fffffbfe4e46a098 > > t5 = 0000000000000020 t6 = fffffbfe4e46a0b8 t7 = fffffc007f4c8000 > > s0 = 0000000000000000 s1 = fffffc0001b0c018 s2 = fffffc0001b0c020 > > s3 = fffffc007b3f5800 s4 = 0000000000000001 s5 = ffffffffc9b9bd85 > > s6 = 0000000000000001 > > a0 = 0000000000000006 a1 = fffffc007b3f5908 a2 = fffffbfe4e46a098 > > a3 = 00000005000108c0 a4 = 0000000000000000 a5 = 0000000000000000 > > t8 = 0000000000000001 t9 = 0000000000000001 t10= 0000000027829f6f > > t11= 0000000000000020 pv = fffffc000031fb60 at = fffffc0000950900 > > gp = fffffc0000940900 sp = fffffc007f4cbca8 [...] > > This patch adds a new callback to alpha_pmu_t for validating the raw > > event encoding with the Linux event types for the PMU, preventing the > > out-of-bounds array access. > > > > Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> > > Cc: Michael Cree <mcree@xxxxxxxxxxxx> > > Cc: Matt Turner <mattst88@xxxxxxxxx> > > Signed-off-by: Will Deacon <will.deacon@xxxxxxx> > > Acked-by: Michael Cree <mcree@xxxxxxxxxxxx> I just remembered about this patch whilst cleaning up some old git branches. Please could you include it in the Alpha tree with a CC stable? Without it, it's trivial to panic a perf-enabled Alpha kernel from userspace. Cheers, Will -- To unsubscribe from this list: send the line "unsubscribe linux-alpha" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
