Merge lp:~mir-team/mir/fix-1465883-and-1341490 into lp:mir

[Daniel van Vugt]

Bump the libmirprotobuf ABI from 0 to 1. Technically we've broken the
ABI plenty of times without bumping. But it becomes a real problem in
the wild when we do a release that also bumps the client ABI.

If you have a newer libmirprotobuf0 used by both an older libmirclient8
and newer libmirclient9 then only libmirclient9 will know the correct
object sizes -- objects that we instantiate on the stack. Existing
clients in that case that still use libmirclient8 will then be
instantiating message objects with the wrong size/structure on the
stack which leads to stack corruption and client crashes.
(LP: #1465883) (LP: #1341490)

And we do wish to keep instantiating message objects on the stack
because that helps with IPC/RPC performance not touching the heap
on every message.

Also keep in mind mirprotobuf is a "private" ABI. We are free to bump
it without needing to bump the public ABIs like libmirclient. Because
clients have no direct dynamic linkage to anything in libmirprotobuf.
.

[PS Jenkins bot (ps-jenkins)]

FAILED: Continuous integration, rev:2674
http://jenkins.qa.ubuntu.com/job/mir-ci/4121/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-vivid-i386-build/2882
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-wily-amd64-build/395
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-vivid-touch/2830/console
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-wily-amd64-ci/277
        deb: http://jenkins.qa.ubuntu.com/job/mir-wily-amd64-ci/277/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/2830
        deb: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/2830/artifact/work/output/*zip*/output.zip
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-runner-mako/5660/console
    SUCCESS: http://s-jenkins.ubuntu-ci:8080/job/touch-flash-device/21243

Click here to trigger a rebuild:
http://s-jenkins.ubuntu-ci:8080/job/mir-ci/4121/rebuild

review: Needs Fixing (continuous-integration)

[Alan Griffiths (alan-griffiths)]

This approach has been tried and rejected

review: Disapprove

Unmerged revisions

2674. By Daniel van Vugt on 2015-06-17

Bump libmirprotobuf ABI from 0 to 1

=== modified file 'debian/control'
--- debian/control	2015-06-17 05:20:42 +0000
+++ debian/control	2015-06-17 06:43:47 +0000
@@ -47,7 +47,7 @@
 # just go ahead. ~mir-team will notice and sync up the code again.
 Vcs-Bzr: https://code.launchpad.net/~mir-team/mir/trunk
 
-Package: libmirprotobuf0
+Package: libmirprotobuf1
 Section: libs
 Architecture: linux-any
 Multi-Arch: same

=== renamed file 'debian/libmirprotobuf0.install' => 'debian/libmirprotobuf1.install'
--- debian/libmirprotobuf0.install	2015-06-16 12:26:32 +0000
+++ debian/libmirprotobuf1.install	2015-06-17 06:43:47 +0000
@@ -1,1 +1,1 @@
-usr/lib/*/libmirprotobuf.so.0
+usr/lib/*/libmirprotobuf.so.1

=== modified file 'src/protobuf/CMakeLists.txt'
--- src/protobuf/CMakeLists.txt	2015-06-17 05:20:42 +0000
+++ src/protobuf/CMakeLists.txt	2015-06-17 06:43:47 +0000
@@ -25,7 +25,7 @@
   ${PROTOBUF_LIBRARIES}
 )
 
-set(MIRPROTOBUF_ABI 0)
+set(MIRPROTOBUF_ABI 1)
 
 set_target_properties(
   mirprotobuf