thermal: intel_powerclamp: Use get_cpu() instead of smp_processor_id() to avoid crash

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: thermal: intel_powerclamp: Use get_cpu() instead of smp_processor_id() to avoid crash When CPU 0 is offline and intel_powerclamp is used to inject idle, it generates kernel BUG: BUG: using smp_processor_id() in preemptible [00000000] code: bash/15687 caller is debug_smp_processor_id+0x17/0x20 CPU: 4 PID: 15687 Comm: bash Not tainted 5.19.0-rc7+ #57 Call Trace: <TASK> dump_stack_lvl+0x49/0x63 dump_stack+0x10/0x16 check_preemption_disabled+0xdd/0xe0 debug_smp_processor_id+0x17/0x20 powerclamp_set_cur_state+0x7f/0xf9 [intel_powerclamp] ... ... Here CPU 0 is the control CPU by default and changed to the current CPU, if CPU 0 offlined. This check has to be performed under cpus_read_lock(), hence the above warning. Use get_cpu() instead of smp_processor_id() to avoid this BUG. [ rjw: Subject edits ]

References

• https://git.kernel.org/stable/c/3e799e815097febbcb81b472285be824f5d089f9
• https://git.kernel.org/stable/c/0f91f66c568b316b19cb042cf50584467b3bdff4
• https://git.kernel.org/stable/c/6904727db0eb62fb0c2dce1cf331c341d97ee4b7
• https://git.kernel.org/stable/c/5a646c38f648185ee2c62f2a19da3c6f04e27612
• https://git.kernel.org/stable/c/513943bf879d45005213e6f5cfb7d9e9943f589f
• https://git.kernel.org/stable/c/5614908434451aafbf9b24cb5247cf1d21269f76
• https://git.kernel.org/stable/c/6e2a347b304224b2aeb1c0ea000d1cf8a02cc592
• https://git.kernel.org/stable/c/418fae0700e85a498062424f8656435c32cdb200
• https://git.kernel.org/stable/c/68b99e94a4a2db6ba9b31fe0485e057b9354a640