netfs: Fix double put of request

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: netfs: Fix double put of request If a netfs request finishes during the pause loop, it will have the ref that belongs to the IN_PROGRESS flag removed at that point - however, if it then goes to the final wait loop, that will *also* put the ref because it sees that the IN_PROGRESS flag is clear and incorrectly assumes that this happened when it called the collector. In fact, since IN_PROGRESS is clear, we shouldn't call the collector again since it's done all the cleanup, such as calling ->ki_complete(). Fix this by making netfs_collect_in_app() just return, indicating that we're done if IN_PROGRESS is removed.

References

• https://git.kernel.org/stable/c/d18facba5a5795ad44b2a00a052e3db2fa77ab12
• https://git.kernel.org/stable/c/9df7b5ebead649b00bf9a53a798e4bf83a1318fd