On Thu, Mar 28, 2019 at 08:37:11PM +0100, Tomas Vondra wrote:
On Thu, Mar 28, 2019 at 07:33:36PM +0100, Tomas Vondra wrote:
On Thu, Mar 28, 2019 at 11:29:12AM -0700, Peter Geoghegan wrote:
On Wed, Mar 27, 2019 at 6:27 PM Tomas Vondra
<tomas.von...@2ndquadrant.com> wrote:
It's a bit too late for pushing emergency fixes over here, so I'll do
more testing tomorrow and then push.
The buildfarm is still almost all-red now. Can you estimate how long
it will take to push a fix?
Half an hour, at most. I have a fix and I'm running tests on it to make
sure it does break something else.
OK, I've pushed the fix. As explained in the commit message, the
deserialization was borked in two ways. Firstly, it was vulnerable to
use-after-free. Secondly, the serialization/deserialization of data for
by-value types did not work for bigendian systems.
I believe this should fix prion (which was tripping on the first issue,
due to using -DRELCACHE_FORCE_RELEASE -DCATCACHE_FORCE_RELEASE) and at
least some of the bigendian boxes (I've tested it on s390x).
OK, this apparently worked fine for all x86 and s390 machines.
I do think there's one remaining issue - the deserialized value is
allocated as a single chunk, and is then "sliced" into smaller buffers.
But the code ignores alignment, which I think may trigger SIGBUS on some
platforms - for example grison, skate or gull fail like this, and those
are ARMv7 and sparc machines.
I do have a fix for that too, but I decided not to push it yet before
testing it a bit more.
I've pushed a fix for this. The short version is that the serialized
representation was not respecting memory alignment requirements, which was
causing issues in machines sensitive to this (ia64, sparc, hppa). It's a
blind attempt, as I currently don't have access to any such machine.
FWIW I've pushed this now so that the machines can test the other stuff,
like jsonpath. I think the serialization/deserialization would deserve a
second look, and I'm wondering if it should work more like ArrayType (i.e.
relying on att_align_* instead of explicit MAXALIGN).
regards
--
Tomas Vondra http://www.2ndQuadrant.com
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