RE: [PATCH] tee: amdtee: fix an IS_ERR() vs NULL bug

[Thomas, Rijo-john]

[Public]

Acked-by: Rijo Thomas <Rijo-john.Thomas@xxxxxxx>

-----Original Message-----
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> 
Sent: Wednesday, November 24, 2021 8:24 PM
To: Jens Wiklander <jens.wiklander@xxxxxxxxxx>; Thomas, Rijo-john <Rijo-john.Thomas@xxxxxxx>
Cc: Sumit Garg <sumit.garg@xxxxxxxxxx>; Rangasamy, Devaraj <Devaraj.Rangasamy@xxxxxxx>; Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>; Gary R Hook <gary.hook@xxxxxxx>; op-tee@xxxxxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx
Subject: [PATCH] tee: amdtee: fix an IS_ERR() vs NULL bug

The __get_free_pages() function does not return error pointers it returns
NULL so fix this condition to avoid a NULL dereference.

Fixes: 757cc3e9ff1d ("tee: add AMD-TEE driver")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
 drivers/tee/amdtee/core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/tee/amdtee/core.c b/drivers/tee/amdtee/core.c
index da6b88e80dc0..297dc62bca29 100644
--- a/drivers/tee/amdtee/core.c
+++ b/drivers/tee/amdtee/core.c
@@ -203,9 +203,8 @@ static int copy_ta_binary(struct tee_context *ctx, void *ptr, void **ta,
 
 	*ta_size = roundup(fw->size, PAGE_SIZE);
 	*ta = (void *)__get_free_pages(GFP_KERNEL, get_order(*ta_size));
-	if (IS_ERR(*ta)) {
-		pr_err("%s: get_free_pages failed 0x%llx\n", __func__,
-		       (u64)*ta);
+	if (!*ta) {
+		pr_err("%s: get_free_pages failed\n", __func__);
 		rc = -ENOMEM;
 		goto rel_fw;
 	}
-- 
2.20.1