On Tue, Jun 23, 2020 at 10:39:26AM -0700, Christian Kujau wrote:
> Hi,
>
> exactly this[0] happened today, on a 5.6.5 kernel:
>
> process '/usr/bin/rsync' started with executable stack
>
> But I can't reproduce this message, and rsync (v3.2.0, not exactly
> abandonware) runs several times a day, so to repeat Andrew's questions[0]
> from last year:
>
> > What are poor users supposed to do if this message comes out?
> > Hopefully google the message and end up at this thread. What do you
> > want to tell them?
>
> Also, the PID is missing from that message.
That's intentional. I for one hate pids.
> I had some long running rsync
> processes running earlier, maybe the RWE status would have been visible in
> /proc/$PID/map, or somewhere else maybe?
If you think process is still running, /proc/*/maps should have 'rwxp'
indeed. You can do quick
$ grep -e '\[stack\]' /proc/*/maps'
to find it.
> $ checksec --format=json --extended --file=`which rsync` | jq
> {
> "/usr/bin/rsync": {
> "relro": "full",
> "canary": "yes",
> "nx": "no",
> "pie": "yes",
> "clangcfi": "no",
> "safestack": "no",
> "rpath": "no",
> "runpath": "no",
> "symbols": "no",
> "fortify_source": "yes",
> "fortified": "10",
> "fortify-able": "19"
> }
> }
$ readelf -l /usr/bin/rsync | grep GNU_STACK -A1
GNU_STACK 0x0000000000000000 0x0000000000000000
0x0000000000000000
0x0000000000000000 0x0000000000000000 RW 0x10
