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don't return if remount of "/" fails in create_sandbox #163

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Dec 18, 2019
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don't return if remount of "/" fails in create_sandbox #163

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1 change: 0 additions & 1 deletion sandbox.c
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Original file line number Diff line number Diff line change
Expand Up @@ -135,7 +135,6 @@ int create_sandbox()
ret = mount("tmpfs", "/", "tmpfs", MS_REMOUNT | MS_RDONLY, "size=0k");
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@giuseppe Why do we need this tmpfs, and why does it fail?

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@AkihiroSuda AkihiroSuda Dec 3, 2019 •
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was it expected to mount tmpfs on /tmp, not /?

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I think the "tmpfs" here is just ignored, the goal is to remount the entire root as read only. We didn't manage to find the reason why it fails in the @rohrschacht use case

if (ret < 0) {
fprintf(stderr, "cannot mount tmpfs on /tmp\n");
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it doesn't seem /tmp?

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yes the error message is wrong here it should mention "cannot remount / as read-only"

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I could add another commit to the PR that changes the error message, if you'd like

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typo is fixed in #170

return ret;
}

ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
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