Moves the access_ok() check for valid memory range from user space from
the function tee_shm_register() to tee_ioctl_shm_register(). With this
we error out early before anything is done that must be undone on error.
Fixes: 578c349570d2 ("tee: add overflow check in register_shm_helper()")
Cc: stable@xxxxxxxxxxxxxxx # 5.10
Reported-by: Pavel Machek <pavel@xxxxxxx>
Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx>
---
Hi,
This patch targets the 5.10.y release to take care of a recently introduced
issue there.
Thanks,
Jens
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 e07f997cf8dd..9cc4a7b63b0d 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 6e662fb131d5..499fccba3d74 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -222,9 +222,6 @@ 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);
--
2.31.1
