Commit 056d3fed3d1f ("tee: add tee_shm_register_{user,kernel}_buf()") refactored tee_shm_register() into corresponding user and kernel space functions named tee_shm_register_{user,kernel}_buf(). The upstream fix commit 573ae4f13f63 ("tee: add overflow check in register_shm_helper()") only applied to tee_shm_register_user_buf().

But the stable kernel 4.19, 5.4, 5.10 and 5.15 don't have the above mentioned tee_shm_register() refactoring commit. Hence a direct backport wasn't possible and the fix has to be rather applied to tee_ioctl_shm_register().

Somehow the fix was correctly backported to 4.19 and 5.4 stable kernels but the backports for 5.10 and 5.15 stable kernels were broken as fix was applied to common tee_shm_register() function which broke its kernel space users such as trusted keys driver.

Fortunately the backport for 5.10 stable kernel was incidently fixed by: commit 606fe84a4185 ("tee: fix memory leak in tee_shm_register()"). So fix the backport for 5.15 stable kernel as well.

Fixes: 578c349570d2 ("tee: add overflow check in register_shm_helper()") Cc: stable@vger.kernel.org # 5.15 Reported-by: Sahil Malhotra sahil.malhotra@nxp.com Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/tee/tee_core.c | 3 +++ drivers/tee/tee_shm.c | 3 --- 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 3fc426dad2df..a44e5b53e7a9 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,9 @@ tee_ioctl_shm_register(struct tee_context *ctx, if (data.flags) return -EINVAL;

+ if (!access_ok((void __user *)(unsigned long)data.addr, data.length)) + return -EFAULT; + shm = tee_shm_register(ctx, data.addr, data.length, TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED); if (IS_ERR(shm)) diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index bd96ebb82c8e..6fb4400333fb 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -223,9 +223,6 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, goto err; }

- if (!access_ok((void __user *)addr, length)) - return ERR_PTR(-EFAULT); - mutex_lock(&teedev->mutex); shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL); mutex_unlock(&teedev->mutex);