diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 22:22:26 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 22:22:26 +0300 |
| commit | 7ae123edd37a47e178eb9a6631fe4a7108262c10 (patch) | |
| tree | 63bb9b285fa6da124cb688b72b6906f32ea85093 | |
| parent | bbcd9c53c743cfee9feb0ee3b25070691d76c5ee (diff) | |
| parent | cc31e9b718dafd8a1bdc593234ddbbf4faa2511c (diff) | |
| download | linux-7ae123edd37a47e178eb9a6631fe4a7108262c10.tar.xz | |
Merge tag 'acpi-urgent-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull two ACPI CPPC fixes from Rafael Wysocki:
"One of them fixes a crash in KVM encountered by Sebastian in
linux-next and introduced by a recent intel_pstate change that caused
the driver to use the ACPI CPPC code and uncovered a missing NULL
pointer check in it.
The other one fixes a possible use-after-free in the same code area.
Summary:
- Fix a crash in KVM encountered in linux-next and introduced by a
recent intel_pstate change that caused the driver to use the ACPI
CPPC code and uncovered a missing NULL pointer check in it
(Sebastian Andrzej Siewior).
- Fix a possible use-after-free in the same code area (Rafael
Wysocki)"
* tag 'acpi-urgent-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / CPPC: Fix per-CPU pointer management in acpi_cppc_processor_probe()
ACPI / CPPC: Fix crash in acpi_cppc_processor_exit()
| -rw-r--r-- | drivers/acpi/cppc_acpi.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index e0ea8f56d2bf..3ca0729f7e0e 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -776,9 +776,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) init_waitqueue_head(&pcc_data.pcc_write_wait_q); } - /* Plug PSD data into this CPUs CPC descriptor. */ - per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; - /* Everything looks okay */ pr_debug("Parsed CPC struct for CPU: %d\n", pr->id); @@ -789,10 +786,15 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) goto out_free; } + /* Plug PSD data into this CPUs CPC descriptor. */ + per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; + ret = kobject_init_and_add(&cpc_ptr->kobj, &cppc_ktype, &cpu_dev->kobj, "acpi_cppc"); - if (ret) + if (ret) { + per_cpu(cpc_desc_ptr, pr->id) = NULL; goto out_free; + } kfree(output.pointer); return 0; @@ -826,6 +828,8 @@ void acpi_cppc_processor_exit(struct acpi_processor *pr) void __iomem *addr; cpc_ptr = per_cpu(cpc_desc_ptr, pr->id); + if (!cpc_ptr) + return; /* Free all the mapped sys mem areas for this CPU */ for (i = 2; i < cpc_ptr->num_entries; i++) { |