wifi: mt76: mt7921: fix error code of return in mt7921_acpi_read

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7921: fix error code of return in mt7921_acpi_read Kernel NULL pointer dereference when ACPI SAR table isn't implemented well. Fix the error code of return to mark the ACPI SAR table as invalid. [ 5.077128] mt7921e 0000:06:00.0: sar cnt = 0 [ 5.077381] BUG: kernel NULL pointer dereference, address: 0000000000000004 [ 5.077630] #PF: supervisor read access in kernel mode [ 5.077883] #PF: error_code(0x0000) - not-present page [ 5.078138] PGD 0 P4D 0 [ 5.078398] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 5.079202] RIP: 0010:mt7921_init_acpi_sar+0x106/0x220 [mt7921_common] ... [ 5.080786] Call Trace: [ 5.080786] <TASK> [ 5.080786] mt7921_register_device+0x37d/0x490 [mt7921_common] [ 5.080786] mt7921_pci_probe.part.0+0x2ee/0x310 [mt7921e] [ 5.080786] mt7921_pci_probe+0x52/0x70 [mt7921e] [ 5.080786] local_pci_probe+0x47/0x90 [ 5.080786] pci_call_probe+0x55/0x190 [ 5.080786] pci_device_probe+0x84/0x120

References

• https://git.kernel.org/stable/c/2a9a5f88e0da71c8e4f30aacbda45b1a1af5469d
• https://git.kernel.org/stable/c/59c2b0aec7a5aa350aa3edfb4363b19348c2269f
• https://git.kernel.org/stable/c/888d89034f9eaeab9b5b75f13dbe35376c7dd471