From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Sat, 6 Jan 2018 12:22:30 +0300
Subject: tee: shm: Potential NULL dereference calling tee_shm_register()
Git-commit: 2490cdf6435b1d3cac0dbf710cd752487c67c296
Patch-mainline: v4.16-rc1
References: fate#325372
get_user_pages_fast() can return zero in certain error paths. We should
handle that or else it means we accidentally return ERR_PTR(0) which is
NULL instead of an error pointer. The callers are not expecting that
and will crash with a NULL dereference.
Fixes: 033ddf12bcf5 ("tee: add register user memory")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
---
drivers/tee/tee_shm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index 6f36da9ee412..556960a1bab3 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -283,7 +283,7 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
if (rc > 0)
shm->num_pages = rc;
if (rc != num_pages) {
- if (rc > 0)
+ if (rc >= 0)
rc = -ENOMEM;
ret = ERR_PTR(rc);
goto err;
--
2.19.1