This is a note to let you know that I've just added the patch titled tee: amdtee: fix memory leak due to reset of global shm list to the 5.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tee-amdtee-fix-memory-leak-due-to-reset-of-global-sh.patch and it can be found in the queue-5.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 5f2b492026d16eed9a7920cefc9642767d5ecd6d Author: Rijo Thomas <Rijo-john.Thomas@xxxxxxx> Date: Wed Nov 4 11:56:09 2020 +0530 tee: amdtee: fix memory leak due to reset of global shm list [ Upstream commit ff1f855804cdbbb6db7b9b6df6cab783d1a40d66 ] The driver maintains a list of shared memory buffers along with their mapped buffer id's in a global linked list. These buffers need to be unmapped after use by the user-space client. The global shared memory list is initialized to zero entries in the function amdtee_open(). This clearing of list entries can be a source for memory leak on secure side if the global linked list previously held some mapped buffer entries allocated from another TEE context. Fix potential memory leak issue by moving global shared memory list to AMD-TEE driver context data structure. Fixes: 757cc3e9ff1d ("tee: add AMD-TEE driver") Reviewed-by: Devaraj Rangasamy <Devaraj.Rangasamy@xxxxxxx> Signed-off-by: Rijo Thomas <Rijo-john.Thomas@xxxxxxx> Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/tee/amdtee/amdtee_private.h b/drivers/tee/amdtee/amdtee_private.h index d7f798c3394bc..97df16a17285a 100644 --- a/drivers/tee/amdtee/amdtee_private.h +++ b/drivers/tee/amdtee/amdtee_private.h @@ -64,9 +64,12 @@ struct amdtee_session { /** * struct amdtee_context_data - AMD-TEE driver context data * @sess_list: Keeps track of sessions opened in current TEE context + * @shm_list: Keeps track of buffers allocated and mapped in current TEE + * context */ struct amdtee_context_data { struct list_head sess_list; + struct list_head shm_list; }; struct amdtee_driver_data { @@ -89,10 +92,6 @@ struct amdtee_shm_data { u32 buf_id; }; -struct amdtee_shm_context { - struct list_head shmdata_list; -}; - #define LOWER_TWO_BYTE_MASK 0x0000FFFF /** diff --git a/drivers/tee/amdtee/core.c b/drivers/tee/amdtee/core.c index 27b4cd77d0db6..ce61c68ec58cb 100644 --- a/drivers/tee/amdtee/core.c +++ b/drivers/tee/amdtee/core.c @@ -20,7 +20,6 @@ static struct amdtee_driver_data *drv_data; static DEFINE_MUTEX(session_list_mutex); -static struct amdtee_shm_context shmctx; static void amdtee_get_version(struct tee_device *teedev, struct tee_ioctl_version_data *vers) @@ -42,7 +41,7 @@ static int amdtee_open(struct tee_context *ctx) return -ENOMEM; INIT_LIST_HEAD(&ctxdata->sess_list); - INIT_LIST_HEAD(&shmctx.shmdata_list); + INIT_LIST_HEAD(&ctxdata->shm_list); ctx->data = ctxdata; return 0; @@ -152,10 +151,11 @@ static struct amdtee_session *find_session(struct amdtee_context_data *ctxdata, u32 get_buffer_id(struct tee_shm *shm) { - u32 buf_id = 0; + struct amdtee_context_data *ctxdata = shm->ctx->data; struct amdtee_shm_data *shmdata; + u32 buf_id = 0; - list_for_each_entry(shmdata, &shmctx.shmdata_list, shm_node) + list_for_each_entry(shmdata, &ctxdata->shm_list, shm_node) if (shmdata->kaddr == shm->kaddr) { buf_id = shmdata->buf_id; break; @@ -333,8 +333,9 @@ int amdtee_close_session(struct tee_context *ctx, u32 session) int amdtee_map_shmem(struct tee_shm *shm) { - struct shmem_desc shmem; + struct amdtee_context_data *ctxdata; struct amdtee_shm_data *shmnode; + struct shmem_desc shmem; int rc, count; u32 buf_id; @@ -362,7 +363,8 @@ int amdtee_map_shmem(struct tee_shm *shm) shmnode->kaddr = shm->kaddr; shmnode->buf_id = buf_id; - list_add(&shmnode->shm_node, &shmctx.shmdata_list); + ctxdata = shm->ctx->data; + list_add(&shmnode->shm_node, &ctxdata->shm_list); pr_debug("buf_id :[%x] kaddr[%p]\n", shmnode->buf_id, shmnode->kaddr); @@ -371,6 +373,7 @@ int amdtee_map_shmem(struct tee_shm *shm) void amdtee_unmap_shmem(struct tee_shm *shm) { + struct amdtee_context_data *ctxdata; struct amdtee_shm_data *shmnode; u32 buf_id; @@ -381,7 +384,8 @@ void amdtee_unmap_shmem(struct tee_shm *shm) /* Unmap the shared memory from TEE */ handle_unmap_shmem(buf_id); - list_for_each_entry(shmnode, &shmctx.shmdata_list, shm_node) + ctxdata = shm->ctx->data; + list_for_each_entry(shmnode, &ctxdata->shm_list, shm_node) if (buf_id == shmnode->buf_id) { list_del(&shmnode->shm_node); kfree(shmnode);