tree a08a42154a0da13fdf582ad266a9700e3774db83
parent 3435a2f7fc89e4ff6cfbce57143bdd85ceed73a5
author Kir Kolyshkin <kolyshkin@gmail.com> 1518045950 -0800
committer Silvin Lubecki <silvin.lubecki@docker.com> 1584958293 +0000

c.RWLayer: check for nil before use

Since commit e9b9e4ace294230c6b8eb has landed, there is a chance that
container.RWLayer is nil (due to some half-removed container). Let's
check the pointer before use to avoid any potential nil pointer
dereferences, resulting in a daemon crash.

Note that even without the abovementioned commit, it's better to perform
an extra check (even it's totally redundant) rather than to have a
possibility of a daemon crash. In other words, better be safe than
sorry.

[v2: add a test case for daemon.getInspectData]
[v3: add a check for container.Dead and a special error for the case]

Fixes: e9b9e4ace294230c6b8eb
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
(cherry picked from commit 195893d38160c0893e326b8674e05ef6714aeaa4)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>