[LibOS] fs/encrypted: Fix crash on dropping a directory handle

[pwmarcz]

Description of the changes

The hdrop callback incorrectly assumed a that handle pointed to a regular file.

This commit also removes this assumption from other callbacks: while in most cases they should not be called for a directory handle, this is not yet a part of a documented contract.

Bug reported in #371 (comment).

How to test this PR?

• Modify the manifest for busybox as specified in RFC: protected files redesign #371 (comment)
• Create /tmp/testdir on host
• Run gramine-direct busybox ls /tmp/testdir

This crashes on master, and is fixed in this PR.

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This change is 

[dimakuv]

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions, not enough approvals from maintainers (2 more required), not enough approvals from different teams (1 more required, approved so far: ITL) (waiting on @pwmarcz)

a discussion (no related file):
Please check Jenkins. It failed.

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-- commits line 4 at r1:
a that -> that a

[pwmarcz]

Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions, not enough approvals from maintainers (2 more required), not enough approvals from different teams (1 more required, approved so far: ITL), "squash! " found in commit messages' one-liners (waiting on @dimakuv)

a discussion (no related file):

Previously, dimakuv (Dmitrii Kuvaiskii) wrote…

Please check Jenkins. It failed.

Yeah, I made a last minute change and it failed to compile... Fixed, hopefully.

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-- commits line 4 at r1:

Previously, dimakuv (Dmitrii Kuvaiskii) wrote…

a that -> that a

I added a squash commit.

[dimakuv]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: all files reviewed, all discussions resolved, not enough approvals from maintainers (1 more required), "squash! " found in commit messages' one-liners

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LibOS/shim/src/fs/chroot/encrypted.c line 390 at r1 (raw file):

    assert(hdl->type == TYPE_CHROOT_ENCRYPTED);
    if (hdl->inode->type != S_IFREG)
        return 0;

Lol :)

[boryspoplawski]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: all files reviewed, all discussions resolved, "squash! " found in commit messages' one-liners

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LibOS/shim/src/fs/chroot/encrypted.c line 389 at r2 (raw file):

static void chroot_encrypted_hdrop(struct shim_handle* hdl) {
    assert(hdl->type == TYPE_CHROOT_ENCRYPTED);
    if (hdl->inode->type != S_IFREG)

Don't we want to add an assert here, similar to other places? not blocking

[pwmarcz]

Reviewable status: all files reviewed, all discussions resolved, "squash! " found in commit messages' one-liners

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LibOS/shim/src/fs/chroot/encrypted.c line 389 at r2 (raw file):

Previously, boryspoplawski (Borys Popławski) wrote…

Don't we want to add an assert here, similar to other places? not blocking

I added the assertion in the other places because they return -EISDIR. In flush and hdrop, I think we don't care.

[dimakuv]

Reviewed all commit messages.
Reviewable status: all files reviewed, all discussions resolved, not enough approvals from maintainers (1 more required)

[boryspoplawski]

Reviewed all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved

[mkow]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved