2015-07-24 11:13:42

by Martin Schwidefsky

Subject: [PATCH] hwrng: correct error check of kthread_run call

The kthread_run() function can return two different error values
but the hwrng core only checks for -ENOMEM. If the other error
value -EINTR is returned it is assigned to hwrng_fill and later
used on a kthread_stop() call which naturally crashes.

Signed-off-by: Martin Schwidefsky <[email protected]>
---
drivers/char/hw_random/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index da8faf7..5643b65 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -429,7 +429,7 @@ static int hwrng_fillfn(void *unused)
static void start_khwrngd(void)
{
hwrng_fill = kthread_run(hwrng_fillfn, NULL, "hwrng");
- if (hwrng_fill == ERR_PTR(-ENOMEM)) {
+ if (IS_ERR(hwrng_fill)) {
pr_err("hwrng_fill thread creation failed");
hwrng_fill = NULL;
}
--
2.3.8

2015-07-28 07:03:13

by Herbert Xu

Subject: Re: [PATCH] hwrng: correct error check of kthread_run call

On Fri, Jul 24, 2015 at 01:13:30PM +0200, Martin Schwidefsky wrote:
> The kthread_run() function can return two different error values
> but the hwrng core only checks for -ENOMEM. If the other error
> value -EINTR is returned it is assigned to hwrng_fill and later
> used on a kthread_stop() call which naturally crashes.
>
> Signed-off-by: Martin Schwidefsky <[email protected]>

Applied to crypto.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt