1400042 - Remove base::SetAllFDsToCloseOnExec

Status: RESOLVED FIXED

(Core :: IPC, enhancement, P3)

Description

[Jed Davis [:jld] ⟨⏰|UTC-7⟩ ⟦he/him⟧]

As the comments around it point out, base::SetAllFDsToCloseOnExec is inherently racy: another thread can create a non-close-on-exec fd after that function is called and before the spawn, which would then leak a copy into the child.  APIs to create fds with the close-on-exec bit already set aren't always portable, and in practice aren't used consistently even when there is a standard.

Currently, SetAllFDsToCloseOnExec is used by process_util_bsd and process_util_mac, because they use posix_spawn rather than fork and can't ru code to iterate open file descriptors in the forked child; I'll file platform-specific bugs for them.

Comment 1

[Jed Davis [:jld] ⟨⏰|UTC-7⟩ ⟦he/him⟧]

Attachment: Bug 1400042 - Remove SetAllFDsToCloseOnExec

As the comments indicate, it has unavoidable race conditions in a
multithreaded program, and its call sites have all been removed.

Comment 2

[Andrew McCreight [:mccr8]]

Comment on attachment 9011169 [details]
Bug 1400042 - Remove SetAllFDsToCloseOnExec

Andrew McCreight [:mccr8] has approved the revision.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/991ffc61729e
Remove SetAllFDsToCloseOnExec r=mccr8

Comment 4

[Raul Gurzau (:RaulG)]

https://hg.mozilla.org/mozilla-central/rev/991ffc61729e