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author | Arnd Bergmann <arnd@arndb.de> | 2021-05-17 17:06:01 +0300 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2021-05-17 17:06:02 +0300 |
commit | 8ec51f894bf54ff9a6ffac4d033690e216a71ab0 (patch) | |
tree | 9d243e4e8f3595fe512e64d24e0627f7ad6823f7 | |
parent | 826b5f76593946ab4a91a73f7b2e3c8eed6bd77f (diff) | |
parent | 9f015b3765bf593b3ed5d3b588e409dc0ffa9f85 (diff) | |
download | linux-8ec51f894bf54ff9a6ffac4d033690e216a71ab0.tar.xz |
Merge tag 'amdtee-fixes-for-v5.13' of git://git.linaro.org/people/jens.wiklander/linux-tee into arm/fixes
AMD-TEE reference count loaded TAs
* tag 'amdtee-fixes-for-v5.13' of git://git.linaro.org/people/jens.wiklander/linux-tee:
tee: amdtee: unload TA only when its refcount becomes 0
Link: https://lore.kernel.org/r/20210505110850.GA3434209@jade
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
-rw-r--r-- | drivers/tee/amdtee/amdtee_private.h | 13 | ||||
-rw-r--r-- | drivers/tee/amdtee/call.c | 94 | ||||
-rw-r--r-- | drivers/tee/amdtee/core.c | 15 |
3 files changed, 106 insertions, 16 deletions
diff --git a/drivers/tee/amdtee/amdtee_private.h b/drivers/tee/amdtee/amdtee_private.h index 337c8d82f74e..6d0f7062bb87 100644 --- a/drivers/tee/amdtee/amdtee_private.h +++ b/drivers/tee/amdtee/amdtee_private.h @@ -21,6 +21,7 @@ #define TEEC_SUCCESS 0x00000000 #define TEEC_ERROR_GENERIC 0xFFFF0000 #define TEEC_ERROR_BAD_PARAMETERS 0xFFFF0006 +#define TEEC_ERROR_OUT_OF_MEMORY 0xFFFF000C #define TEEC_ERROR_COMMUNICATION 0xFFFF000E #define TEEC_ORIGIN_COMMS 0x00000002 @@ -93,6 +94,18 @@ struct amdtee_shm_data { u32 buf_id; }; +/** + * struct amdtee_ta_data - Keeps track of all TAs loaded in AMD Secure + * Processor + * @ta_handle: Handle to TA loaded in TEE + * @refcount: Reference count for the loaded TA + */ +struct amdtee_ta_data { + struct list_head list_node; + u32 ta_handle; + u32 refcount; +}; + #define LOWER_TWO_BYTE_MASK 0x0000FFFF /** diff --git a/drivers/tee/amdtee/call.c b/drivers/tee/amdtee/call.c index 096dd4d92d39..07f36ac834c8 100644 --- a/drivers/tee/amdtee/call.c +++ b/drivers/tee/amdtee/call.c @@ -121,15 +121,69 @@ static int amd_params_to_tee_params(struct tee_param *tee, u32 count, return ret; } +static DEFINE_MUTEX(ta_refcount_mutex); +static struct list_head ta_list = LIST_HEAD_INIT(ta_list); + +static u32 get_ta_refcount(u32 ta_handle) +{ + struct amdtee_ta_data *ta_data; + u32 count = 0; + + /* Caller must hold a mutex */ + list_for_each_entry(ta_data, &ta_list, list_node) + if (ta_data->ta_handle == ta_handle) + return ++ta_data->refcount; + + ta_data = kzalloc(sizeof(*ta_data), GFP_KERNEL); + if (ta_data) { + ta_data->ta_handle = ta_handle; + ta_data->refcount = 1; + count = ta_data->refcount; + list_add(&ta_data->list_node, &ta_list); + } + + return count; +} + +static u32 put_ta_refcount(u32 ta_handle) +{ + struct amdtee_ta_data *ta_data; + u32 count = 0; + + /* Caller must hold a mutex */ + list_for_each_entry(ta_data, &ta_list, list_node) + if (ta_data->ta_handle == ta_handle) { + count = --ta_data->refcount; + if (count == 0) { + list_del(&ta_data->list_node); + kfree(ta_data); + break; + } + } + + return count; +} + int handle_unload_ta(u32 ta_handle) { struct tee_cmd_unload_ta cmd = {0}; - u32 status; + u32 status, count; int ret; if (!ta_handle) return -EINVAL; + mutex_lock(&ta_refcount_mutex); + + count = put_ta_refcount(ta_handle); + + if (count) { + pr_debug("unload ta: not unloading %u count %u\n", + ta_handle, count); + ret = -EBUSY; + goto unlock; + } + cmd.ta_handle = ta_handle; ret = psp_tee_process_cmd(TEE_CMD_ID_UNLOAD_TA, (void *)&cmd, @@ -137,8 +191,12 @@ int handle_unload_ta(u32 ta_handle) if (!ret && status != 0) { pr_err("unload ta: status = 0x%x\n", status); ret = -EBUSY; + } else { + pr_debug("unloaded ta handle %u\n", ta_handle); } +unlock: + mutex_unlock(&ta_refcount_mutex); return ret; } @@ -340,7 +398,8 @@ int handle_open_session(struct tee_ioctl_open_session_arg *arg, u32 *info, int handle_load_ta(void *data, u32 size, struct tee_ioctl_open_session_arg *arg) { - struct tee_cmd_load_ta cmd = {0}; + struct tee_cmd_unload_ta unload_cmd = {}; + struct tee_cmd_load_ta load_cmd = {}; phys_addr_t blob; int ret; @@ -353,21 +412,36 @@ int handle_load_ta(void *data, u32 size, struct tee_ioctl_open_session_arg *arg) return -EINVAL; } - cmd.hi_addr = upper_32_bits(blob); - cmd.low_addr = lower_32_bits(blob); - cmd.size = size; + load_cmd.hi_addr = upper_32_bits(blob); + load_cmd.low_addr = lower_32_bits(blob); + load_cmd.size = size; - ret = psp_tee_process_cmd(TEE_CMD_ID_LOAD_TA, (void *)&cmd, - sizeof(cmd), &arg->ret); + mutex_lock(&ta_refcount_mutex); + + ret = psp_tee_process_cmd(TEE_CMD_ID_LOAD_TA, (void *)&load_cmd, + sizeof(load_cmd), &arg->ret); if (ret) { arg->ret_origin = TEEC_ORIGIN_COMMS; arg->ret = TEEC_ERROR_COMMUNICATION; - } else { - set_session_id(cmd.ta_handle, 0, &arg->session); + } else if (arg->ret == TEEC_SUCCESS) { + ret = get_ta_refcount(load_cmd.ta_handle); + if (!ret) { + arg->ret_origin = TEEC_ORIGIN_COMMS; + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + + /* Unload the TA on error */ + unload_cmd.ta_handle = load_cmd.ta_handle; + psp_tee_process_cmd(TEE_CMD_ID_UNLOAD_TA, + (void *)&unload_cmd, + sizeof(unload_cmd), &ret); + } else { + set_session_id(load_cmd.ta_handle, 0, &arg->session); + } } + mutex_unlock(&ta_refcount_mutex); pr_debug("load TA: TA handle = 0x%x, RO = 0x%x, ret = 0x%x\n", - cmd.ta_handle, arg->ret_origin, arg->ret); + load_cmd.ta_handle, arg->ret_origin, arg->ret); return 0; } diff --git a/drivers/tee/amdtee/core.c b/drivers/tee/amdtee/core.c index 8a6a8f30bb42..da6b88e80dc0 100644 --- a/drivers/tee/amdtee/core.c +++ b/drivers/tee/amdtee/core.c @@ -59,10 +59,9 @@ static void release_session(struct amdtee_session *sess) continue; handle_close_session(sess->ta_handle, sess->session_info[i]); + handle_unload_ta(sess->ta_handle); } - /* Unload Trusted Application once all sessions are closed */ - handle_unload_ta(sess->ta_handle); kfree(sess); } @@ -224,8 +223,6 @@ static void destroy_session(struct kref *ref) struct amdtee_session *sess = container_of(ref, struct amdtee_session, refcount); - /* Unload the TA from TEE */ - handle_unload_ta(sess->ta_handle); mutex_lock(&session_list_mutex); list_del(&sess->list_node); mutex_unlock(&session_list_mutex); @@ -238,7 +235,7 @@ int amdtee_open_session(struct tee_context *ctx, { struct amdtee_context_data *ctxdata = ctx->data; struct amdtee_session *sess = NULL; - u32 session_info; + u32 session_info, ta_handle; size_t ta_size; int rc, i; void *ta; @@ -259,11 +256,14 @@ int amdtee_open_session(struct tee_context *ctx, if (arg->ret != TEEC_SUCCESS) goto out; + ta_handle = get_ta_handle(arg->session); + mutex_lock(&session_list_mutex); sess = alloc_session(ctxdata, arg->session); mutex_unlock(&session_list_mutex); if (!sess) { + handle_unload_ta(ta_handle); rc = -ENOMEM; goto out; } @@ -277,6 +277,7 @@ int amdtee_open_session(struct tee_context *ctx, if (i >= TEE_NUM_SESSIONS) { pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS); + handle_unload_ta(ta_handle); kref_put(&sess->refcount, destroy_session); rc = -ENOMEM; goto out; @@ -289,12 +290,13 @@ int amdtee_open_session(struct tee_context *ctx, spin_lock(&sess->lock); clear_bit(i, sess->sess_mask); spin_unlock(&sess->lock); + handle_unload_ta(ta_handle); kref_put(&sess->refcount, destroy_session); goto out; } sess->session_info[i] = session_info; - set_session_id(sess->ta_handle, i, &arg->session); + set_session_id(ta_handle, i, &arg->session); out: free_pages((u64)ta, get_order(ta_size)); return rc; @@ -329,6 +331,7 @@ int amdtee_close_session(struct tee_context *ctx, u32 session) /* Close the session */ handle_close_session(ta_handle, session_info); + handle_unload_ta(ta_handle); kref_put(&sess->refcount, destroy_session); |