1363844 - Add flag to DLL blocklist to make a block specific to child processes

Status: RESOLVED FIXED

(Core :: General, enhancement)

Description

[(No longer employed by Mozilla) Aaron Klotz]

I wrote this code as part of a test for bug 1361230. I think this would be useful in general in case there are DLLs that are legit injections in the parent but not wanted in child processes.

Comment 1

[(No longer employed by Mozilla) Aaron Klotz]

Attachment: Add CHILD_PROCESSES_ONLY flag to DLL blocklist

Since the blocklist doesn't have the luxury of being able to call XRE_IsParentProcess() during its initialization, I have added a parameter to DllBlocklist_Initialize to set whether the blocklist should consider itself to be in a parent process or not, and have updated the various callsites accordingly.

Comment 2

[(Away)]

Comment on attachment 8866481 [details] [diff] [review]
Add CHILD_PROCESSES_ONLY flag to DLL blocklist

Review of attachment 8866481 [details] [diff] [review]:
-----------------------------------------------------------------

Would be nice to use some enum like GeckoProcessType instead of the boolean, but I assume you can't use GeckoProcessType from here. What do you think about defining another one-off enum { PARENT, CHILD } here? Maybe that would be too much duplication. Failing that, at least an inline comment foo(/* myParam = */ true) would help to clarify.

::: mozglue/build/WindowsDllBlocklist.cpp
@@ +72,5 @@
>    enum {
>      FLAGS_DEFAULT = 0,
>      BLOCK_WIN8PLUS_ONLY = 1,
>      USE_TIMESTAMP = 4,
> +    CHILD_PROCESSES_ONLY = 8

Feel free to fill in the gap with `2` here.

Comment 3

[(No longer employed by Mozilla) Aaron Klotz]

(In reply to David Major [:dmajor] from comment #2)
> Comment on attachment 8866481 [details] [diff] [review]
> Would be nice to use some enum like GeckoProcessType instead of the boolean,
> but I assume you can't use GeckoProcessType from here. What do you think
> about defining another one-off enum { PARENT, CHILD } here?

Yeah, I was kinda unhappy with that too. Will replace with an enum.

Comment 4

[(No longer employed by Mozilla) Aaron Klotz]

https://hg.mozilla.org/integration/mozilla-inbound/rev/7b2c34b67962af59f9f9cb2ec89414811aac0d9f
Bug 1363844: Add CHILD_PROCESSES_ONLY flag to Windows DLL blocklist; r=dmajor

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/7b2c34b67962