[PATCH 2/2] firmware: qcom: qcom_tzmem: Implement sanity checks

[Kuldeep Singh]

The qcom_tzmem driver currently has multiple exposed APIs that lack
validations on input parameters. This oversight can lead to unexpected
crashes due to null pointer dereference when incorrect inputs are
provided.

To address this issue, add required sanity for all input parameters in
the exposed APIs.

Signed-off-by: Kuldeep Singh <quic_kuldsing@xxxxxxxxxxx>
---
 drivers/firmware/qcom/qcom_tzmem.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c
index 92b365178235..2f2e1f2fa9fc 100644
--- a/drivers/firmware/qcom/qcom_tzmem.c
+++ b/drivers/firmware/qcom/qcom_tzmem.c
@@ -203,6 +203,9 @@ qcom_tzmem_pool_new(const struct qcom_tzmem_pool_config *config)
 
 	might_sleep();
 
+	if (!config || !config->policy)
+		return ERR_PTR(-EINVAL);
+
 	switch (config->policy) {
 	case QCOM_TZMEM_POLICY_STATIC:
 		if (!config->initial_size)
@@ -316,6 +319,9 @@ devm_qcom_tzmem_pool_new(struct device *dev,
 	struct qcom_tzmem_pool *pool;
 	int ret;
 
+	if (!dev || !config)
+		return ERR_PTR(-EINVAL);
+
 	pool = qcom_tzmem_pool_new(config);
 	if (IS_ERR(pool))
 		return pool;
@@ -366,7 +372,7 @@ void *qcom_tzmem_alloc(struct qcom_tzmem_pool *pool, size_t size, gfp_t gfp)
 	unsigned long vaddr;
 	int ret;
 
-	if (!size)
+	if (!pool || !size)
 		return NULL;
 
 	size = PAGE_ALIGN(size);
@@ -412,6 +418,9 @@ void qcom_tzmem_free(void *vaddr)
 {
 	struct qcom_tzmem_chunk *chunk;
 
+	if (!vaddr)
+		return;
+
 	scoped_guard(spinlock_irqsave, &qcom_tzmem_chunks_lock)
 		chunk = radix_tree_delete_item(&qcom_tzmem_chunks,
 					       (unsigned long)vaddr, NULL);
@@ -446,6 +455,9 @@ phys_addr_t qcom_tzmem_to_phys(void *vaddr)
 	void __rcu **slot;
 	phys_addr_t ret;
 
+	if (!vaddr)
+		return 0;
+
 	guard(spinlock_irqsave)(&qcom_tzmem_chunks_lock);
 
 	radix_tree_for_each_slot(slot, &qcom_tzmem_chunks, &iter, 0) {
@@ -466,6 +478,9 @@ EXPORT_SYMBOL_GPL(qcom_tzmem_to_phys);
 
 int qcom_tzmem_enable(struct device *dev)
 {
+	if (!dev)
+		return -EINVAL;
+
 	if (qcom_tzmem_dev)
 		return -EBUSY;
 
-- 
2.34.1