aoe: avoid potential deadlock at set_capacity

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: aoe: avoid potential deadlock at set_capacity Move set_capacity() outside of the section procected by (&d->lock). To avoid possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- [1] lock(&bdev->bd_size_lock); local_irq_disable(); [2] lock(&d->lock); [3] lock(&bdev->bd_size_lock); <Interrupt> [4] lock(&d->lock); *** DEADLOCK *** Where [1](&bdev->bd_size_lock) hold by zram_add()->set_capacity(). [2]lock(&d->lock) hold by aoeblk_gdalloc(). And aoeblk_gdalloc() is trying to acquire [3](&bdev->bd_size_lock) at set_capacity() call. In this situation an attempt to acquire [4]lock(&d->lock) from aoecmd_cfg_rsp() will lead to deadlock. So the simplest solution is breaking lock dependency [2](&d->lock) -> [3](&bdev->bd_size_lock) by moving set_capacity() outside.

References

• https://git.kernel.org/stable/c/2499fa286fb010ceb289950050199f33c26667b9
• https://git.kernel.org/stable/c/2d623c94fbba3554f4446ba6f3c764994e8b0d26
• https://git.kernel.org/stable/c/673629018ba04906899dcb631beec34d871f709c
• https://git.kernel.org/stable/c/19a77b27163820f793b4d022979ffdca8f659b77
• https://git.kernel.org/stable/c/e169bd4fb2b36c4b2bee63c35c740c85daeb2e86