[PATCH 4.1 52/84] hwrng: core - correct error check of kthread_run call

From: Greg Kroah-Hartman
Date: Fri Aug 14 2015 - 14:17:21 EST


4.1-stable review patch. If anyone has any objections, please let me know.

------------------

From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>

commit 17fb874dee093139923af8ed36061faa92cc8e79 upstream.

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 <schwidefsky@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/char/hw_random/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- 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;
}


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/