CVE-2022-49433: Use of Uninitialized Resource

In the Linux kernel, the following vulnerability has been resolved:

RDMA/hfi1: Prevent use of lock before it is initialized

If there is a failure during probe of hfi1 before the sdma_map_lock is initialized, the call to hfi1_free_devdata() will attempt to use a lock that has not been initialized. If the locking correctness validator is on then an INFO message and stack trace resembling the following may be seen:

INFO: trying to register non-static key. The code is fine but needs lockdep annotation, or maybe you didn't initialize this object before use? turning off the locking correctness validator. Call Trace: register_lock_class+0x11b/0x880 __lock_acquire+0xf3/0x7930 lock_acquire+0xff/0x2d0 _raw_spin_lock_irq+0x46/0x60 sdma_clean+0x42a/0x660 [hfi1] hfi1_free_devdata+0x3a7/0x420 [hfi1] init_one+0x867/0x11a0 [hfi1] pci_device_probe+0x40e/0x8d0

The use of sdma_map_lock in sdma_clean() is for freeing the sdma_map memory, and sdma_map is not allocated/initialized until after sdma_map_lock has been initialized. This code only needs to be run if sdma_map is not NULL, and so checking for that condition will avoid trying to use the lock before it is initialized.