[PATCH 5.4 02/27] tee: Correct inappropriate usage of TEE_SHM_DMA_BUF flag

Greg Kroah-Hartman
2021-08-13T15:15:41Z

From: Sumit Garg <sumit.garg@linaro.org>

[ Upstream commit 376e4199e327a5cf29b8ec8fb0f64f3d8b429819 ]

Currently TEE_SHM_DMA_BUF flag has been inappropriately used to not
register shared memory allocated for private usage by underlying TEE
driver: OP-TEE in this case. So rather add a new flag as TEE_SHM_PRIV
that can be utilized by underlying TEE drivers for private allocation
and usage of shared memory.

With this corrected, allow tee_shm_alloc_kernel_buf() to allocate a
shared memory region without the backing of dma-buf.

Cc: stable@vger.kernel.org
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Co-developed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/tee/optee/call.c | 2 +-
drivers/tee/optee/core.c | 3 ++-
drivers/tee/optee/rpc.c | 5 +++--
drivers/tee/optee/shm_pool.c | 8 ++++++--
drivers/tee/tee_shm.c | 4 ++--
include/linux/tee_drv.h | 1 +
6 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
index 4b5069f88d78..3a54455d9ddf 100644
--- a/drivers/tee/optee/call.c
+++ b/drivers/tee/optee/call.c
@@ -181,7 +181,7 @@ static struct tee_shm *get_msg_arg(struct tee_context *ctx, size_t num_params,
struct optee_msg_arg *ma;

shm = tee_shm_alloc(ctx, OPTEE_MSG_GET_ARG_SIZE(num_params),
- TEE_SHM_MAPPED);
+ TEE_SHM_MAPPED | TEE_SHM_PRIV);
if (IS_ERR(shm))
return shm;

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index 432dd38921dd..4bb4c8f28cbd 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -254,7 +254,8 @@ static void optee_release(struct tee_context *ctx)
if (!ctxdata)
return;

- shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg), TEE_SHM_MAPPED);
+ shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg),
+ TEE_SHM_MAPPED | TEE_SHM_PRIV);
if (!IS_ERR(shm)) {
arg = tee_shm_get_va(shm, 0);
/*
diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
index b4ade54d1f28..aecf62016e7b 100644
--- a/drivers/tee/optee/rpc.c
+++ b/drivers/tee/optee/rpc.c
@@ -220,7 +220,7 @@ static void handle_rpc_func_cmd_shm_alloc(struct tee_context *ctx,
shm = cmd_alloc_suppl(ctx, sz);
break;
case OPTEE_MSG_RPC_SHM_TYPE_KERNEL:
- shm = tee_shm_alloc(ctx, sz, TEE_SHM_MAPPED);
+ shm = tee_shm_alloc(ctx, sz, TEE_SHM_MAPPED | TEE_SHM_PRIV);
break;
default:
arg->ret = TEEC_ERROR_BAD_PARAMETERS;
@@ -405,7 +405,8 @@ void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param,

switch (OPTEE_SMC_RETURN_GET_RPC_FUNC(param->a0)) {
case OPTEE_SMC_RPC_FUNC_ALLOC:
- shm = tee_shm_alloc(ctx, param->a1, TEE_SHM_MAPPED);
+ shm = tee_shm_alloc(ctx, param->a1,
+ TEE_SHM_MAPPED | TEE_SHM_PRIV);
if (!IS_ERR(shm) && !tee_shm_get_pa(shm, 0, &pa)) {
reg_pair_from_64(&param->a1, &param->a2, pa);
reg_pair_from_64(&param->a4, &param->a5,
diff --git a/drivers/tee/optee/shm_pool.c b/drivers/tee/optee/shm_pool.c
index da06ce9b9313..c41a9a501a6e 100644
--- a/drivers/tee/optee/shm_pool.c
+++ b/drivers/tee/optee/shm_pool.c
@@ -27,7 +27,11 @@ static int pool_op_alloc(struct tee_shm_pool_mgr *poolm,
shm->paddr = page_to_phys(page);
shm->size = PAGE_SIZE << order;

- if (shm->flags & TEE_SHM_DMA_BUF) {
+ /*
+ * Shared memory private to the OP-TEE driver doesn't need
+ * to be registered with OP-TEE.
+ */
+ if (!(shm->flags & TEE_SHM_PRIV)) {
unsigned int nr_pages = 1 << order, i;
struct page **pages;

@@ -60,7 +64,7 @@ err:
static void pool_op_free(struct tee_shm_pool_mgr *poolm,
struct tee_shm *shm)
{
- if (shm->flags & TEE_SHM_DMA_BUF)
+ if (!(shm->flags & TEE_SHM_PRIV))
optee_shm_unregister(shm->ctx, shm);

free_pages((unsigned long)shm->kaddr, get_order(shm->size));
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index 1b4b4a1ba91d..d6491e973fa4 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -117,7 +117,7 @@ static struct tee_shm *__tee_shm_alloc(struct tee_context *ctx,
return ERR_PTR(-EINVAL);
}

- if ((flags & ~(TEE_SHM_MAPPED | TEE_SHM_DMA_BUF))) {
+ if ((flags & ~(TEE_SHM_MAPPED | TEE_SHM_DMA_BUF | TEE_SHM_PRIV))) {
dev_err(teedev->dev.parent, "invalid shm flags 0x%x", flags);
return ERR_PTR(-EINVAL);
}
@@ -233,7 +233,7 @@ EXPORT_SYMBOL_GPL(tee_shm_priv_alloc);
*/
struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size)
{
- return tee_shm_alloc(ctx, size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
+ return tee_shm_alloc(ctx, size, TEE_SHM_MAPPED);
}
EXPORT_SYMBOL_GPL(tee_shm_alloc_kernel_buf);

diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 91677f2fa2e8..cd15c1b7fae0 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -26,6 +26,7 @@
#define TEE_SHM_REGISTER BIT(3) /* Memory registered in secure world */
#define TEE_SHM_USER_MAPPED BIT(4) /* Memory mapped in user space */
#define TEE_SHM_POOL BIT(5) /* Memory allocated from pool */
+#define TEE_SHM_PRIV BIT(7) /* Memory private to TEE driver */

struct device;
struct tee_device;
--
2.30.2