From: Pierre Gondois <pierre.gondois@arm.com>
[ Upstream commit de0df442ee49cb1f6ee58f3fec5dcb5e5eb70aab ]
The DeviceTree Specification v0.3 specifies that the cache node
'[d-|i-|]cache-size' property is required. The 'cache-unified'
property is specifies whether the cache level is separate
or unified.
If the cache-size property is missing, no cache leaves is accounted.
This can lead to a 'BUG: KASAN: slab-out-of-bounds' [1] bug.
Check 'cache-unified' property and always account for at least
one cache leaf when parsing the device tree.
[1] https://lore.kernel.org/all/0f19cb3f-d6cf-4032-66d2-dedc9d09a0e3@linaro.org/
Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230104183033.755668-4-pierre.gondois@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Wen Yang <wen.yang@linux.dev>
---
drivers/base/cacheinfo.c | 37 ++++++++++++++++++++++++++-----------
1 file changed, 26 insertions(+), 11 deletions(-)
diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
index 480007210bcc..ab99b0f0d010 100644
--- a/drivers/base/cacheinfo.c
+++ b/drivers/base/cacheinfo.c
@@ -224,12 +224,9 @@ static int cache_setup_of_node(unsigned int cpu)
return 0;
}
-int init_of_cache_level(unsigned int cpu)
+static int of_count_cache_leaves(struct device_node *np)
{
- struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
- struct device_node *np = of_cpu_device_node_get(cpu);
- struct device_node *prev = NULL;
- unsigned int levels = 0, leaves = 0, level;
+ unsigned int leaves = 0;
if (of_property_read_bool(np, "cache-size"))
++leaves;
@@ -237,6 +234,28 @@ int init_of_cache_level(unsigned int cpu)
++leaves;
if (of_property_read_bool(np, "d-cache-size"))
++leaves;
+
+ if (!leaves) {
+ /* The '[i-|d-|]cache-size' property is required, but
+ * if absent, fallback on the 'cache-unified' property.
+ */
+ if (of_property_read_bool(np, "cache-unified"))
+ return 1;
+ else
+ return 2;
+ }
+
+ return leaves;
+}
+
+int init_of_cache_level(unsigned int cpu)
+{
+ struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+ struct device_node *np = of_cpu_device_node_get(cpu);
+ struct device_node *prev = NULL;
+ unsigned int levels = 0, leaves, level;
+
+ leaves = of_count_cache_leaves(np);
if (leaves > 0)
levels = 1;
@@ -250,12 +269,8 @@ int init_of_cache_level(unsigned int cpu)
goto err_out;
if (level <= levels)
goto err_out;
- if (of_property_read_bool(np, "cache-size"))
- ++leaves;
- if (of_property_read_bool(np, "i-cache-size"))
- ++leaves;
- if (of_property_read_bool(np, "d-cache-size"))
- ++leaves;
+
+ leaves += of_count_cache_leaves(np);
levels = level;
}
--
2.25.1