[PATCH 19.07 ubus 0/3] backport fixes for UAF and other issues

[Petr Štetiar]

Hi,

I would like to backport following fixes, where at least commit 2099bb3ad997
("libubus: use list_empty/list_first_entry in ubus_process_pending_msg") fixes
UAF issue I've introduced in commit c5f2053dfcfd ("workaround possibly false
positive uses of memory after it is freed") while fixing another false
positive UAF reported[1] by clang's static analyzer.

Those fixes are being used in master/21.02 for about 6 months, so should be
tested enough and considered for backporting. I've just runtested those fixes
on mvebu/turris-omnia and ipq40xx/glinet-b1300 devices.

1. https://openwrt.gitlab.io/-/project/ubus/-/jobs/2096090992/artifacts/build/scan/2022-02-15-150310-70-1/index.html

Cheers,

Petr

Felix Fietkau (3):
  libubus: use list_empty/list_first_entry in ubus_process_pending_msg
  libubus: process pending messages in data handler if stack depth is 0
  libubus: increase stack depth for processing obj msgs

 libubus-io.c | 10 +++++++++-
 libubus.c    |  7 +++++--
 2 files changed, 14 insertions(+), 3 deletions(-)