2019-02-20 06:05:02

by Sumit Garg

Subject: [PATCH -next] tee: fix possible error pointer ctx dereferencing

Add check for valid ctx pointer and then only dereference ctx to
configure supp_nowait flag.

Fixes: 42bf4152d8a7 ("tee: add supp_nowait flag in tee_context struct")
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Sumit Garg <[email protected]>
---
drivers/tee/tee_core.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 25f3b9c..06fbfc0 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -993,7 +993,9 @@ tee_client_open_context(struct tee_context *start,
* tee_client_open_session() if any in kernel client requires
* different behaviour.
*/
- ctx->supp_nowait = true;
+ if (!IS_ERR(ctx))
+ ctx->supp_nowait = true;
+
return ctx;
}
EXPORT_SYMBOL_GPL(tee_client_open_context);
--
2.7.4

2019-02-22 08:10:36

by Jens Wiklander

Subject: Re: [PATCH -next] tee: fix possible error pointer ctx dereferencing

Hi,

On Wed, Feb 20, 2019 at 7:02 AM Sumit Garg <[email protected]> wrote:
>
> Add check for valid ctx pointer and then only dereference ctx to
> configure supp_nowait flag.
>
> Fixes: 42bf4152d8a7 ("tee: add supp_nowait flag in tee_context struct")
> Reported-by: Dan Carpenter <[email protected]>
> Signed-off-by: Sumit Garg <[email protected]>
> ---
> drivers/tee/tee_core.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)

I see that Arnd picked this one up the arm/drivers branch too. Thanks
for the help Arnd!

Cheers,
Jens