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authorLinus Torvalds <torvalds@linux-foundation.org>2016-12-14 22:22:26 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-14 22:22:26 +0300
commit7ae123edd37a47e178eb9a6631fe4a7108262c10 (patch)
tree63bb9b285fa6da124cb688b72b6906f32ea85093 /drivers
parentbbcd9c53c743cfee9feb0ee3b25070691d76c5ee (diff)
parentcc31e9b718dafd8a1bdc593234ddbbf4faa2511c (diff)
downloadlinux-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()
Diffstat (limited to 'drivers')
-rw-r--r--drivers/acpi/cppc_acpi.c12
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++) {