Hi!
From: Jens Wiklander jens.wiklander@linaro.org
commit 573ae4f13f630d6660008f1974c0a8a29c30e18a upstream.
With special lengths supplied by user space, register_shm_helper() has an integer overflow when calculating the number of pages covered by a supplied user space memory region.
This causes internal_get_user_pages_fast() a helper function of pin_user_pages_fast() to do a NULL pointer dereference:
Maybe this needs fixing, but this fix adds a memory leak or two. Note the goto err, that needs to be done.
Best regards, Pavel
Signed-off-by: Pavel Machek pavel@denx.de
+++ b/drivers/tee/tee_shm.c @@ -222,6 +222,9 @@ struct tee_shm *tee_shm_register(struct 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);
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 6e662fb131d5..283fa50676a2 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -222,8 +222,10 @@ 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); + if (!access_ok((void __user *)addr, length)) { + ret = ERR_PTR(-EFAULT); + goto err; + }
mutex_lock(&teedev->mutex); shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL);