On Wed, May 18, 2016 at 8:51 PM, Rob Herring <robh@xxxxxxxxxx> wrote: > On Wed, May 18, 2016 at 7:23 PM, Rob Herring <robh@xxxxxxxxxx> wrote: >> On Wed, May 18, 2016 at 4:26 PM, Rhyland Klein <rklein@xxxxxxxxxx> wrote: >>> On 5/18/2016 3:58 PM, Rhyland Klein wrote: >>>> On 5/18/2016 3:36 PM, Rob Herring wrote: >>>>> On Wed, May 18, 2016 at 10:34 AM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: >>>>>> Hi Rhyland, >>>>>> >>>>>> I'm seeing a crash on boot that seems to have been caused by >>>>>> "drivers/of: Fix depth when unflattening devicetree": >>>>>> >>>>>> [ 61.145229] ================================================================== >>>>>> >>>>>> [ 61.147588] BUG: KASAN: stack-out-of-bounds in unflatten_dt_nodes+0x11d2/0x1290 at addr ffff88005b30777c > > [...] > >>> This patch seems to work for me. I found a bug in my original patch. >>> Sasha/Rob, can you see if this works for you too: >>> >>> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c >>> index 0b5850027bb5..e7a8caac5b27 100644 >>> --- a/drivers/of/fdt.c >>> +++ b/drivers/of/fdt.c >>> @@ -407,9 +407,9 @@ static int unflatten_dt_nodes(const void *blob, >>> >>> root = dad; >>> fpsizes[depth] = dad ? strlen(of_node_full_name(dad)) : 0; >>> - nps[depth+1] = dad; >>> + nps[depth] = dad; >>> for (offset = 0; >>> - offset >= 0; >>> + offset >= 0 && depth >= 0; >>> offset = fdt_next_node(blob, offset, &depth)) { >>> if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH)) >>> continue; >> >> This is not work for me. I'm booting x86 with the DT unit test and >> KASAN enabled. I suspect our differences are due to different data >> after the end of the dtb. Also, I think there may be a bug in >> fdt_next_node FDT_END handling. The "!depth" seems suspicious to me >> and I think it should be "!(*depth)". I take that back. Your change does work for me. Must have had something stale. >> The DT overlay unit tests are also failing. Not sure if that's related. > > Seems with the above patch and the fix to fdt_next_node, the problem > is fixed both for KASAN and the DT overlay tests. Trying it out now > with some other configurations. fdt_next_node is in fact correct. Changing it caused failures in the dtc unit tests. So I have squashed the above fix into your original fix and pushed that out to -next. kernelci.org is also seeing some failures due to this. I'll give this another day or so before sending to Linus. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html