Unshare from user must lock path to avoid recipient access

[PVince81]

Steps to reproduce

1. Enable transactional file locking
2. Create two users "user1" and "user2"
3. Login as "user1"
4. Create a folder "test"
5. Share "test" with "user2"
6. Add sleep(30); here to delay the unshare operation:

   core/lib/private/share/share.php

   Line 800 in b88a0e7

   $toDelete = array();

7. Unshare "test" from "user2"
8. At the same time, try downloading or modifying the contents of the folder "test" as user2 (recipient)

Expected result

Folder "test" is exclusively locked.

Actual result

Folder can still be tempered with while the unshare operation is running.

Version

ownCloud 8.1 git master b88a0e7

Note: this should also prevent two unshare operations to run in parallel.

[PVince81]

@jnfrmarks @icewind1991 @schiesbn

[PVince81]

@DeepDiver1975 @cmonteroluque I scheduled to 8.2, I don't think there is time left for this

[PVince81]

Not sure if sev high or medium as I don't know what kind of breakage could happen.
@schiesbn do you see anything bad happening (ex: data loss) when updating sharing keys during an unshare while people access the files ?

[ghost]

This issue will fall off 8.2 if not resolved by 6 Oct

[ownclouders]

Hey, this issue has been closed because the label status/STALE is set and there were no updates for 7 days. Feel free to reopen this issue if you deem it appropriate.

(This is an automated comment from GitMate.io.)

[ownclouders]

Hey, this issue has been closed because the label status/STALE is set and there were no updates for 7 days. Feel free to reopen this issue if you deem it appropriate.

(This is an automated comment from GitMate.io.)

[stale]

This issue has been automatically closed.