lkml.org 
[lkml]   [2019]   [Sep]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH] drm/amdkfd: fix a potential NULL pointer dereference
Date
On 2019-09-18 12:30 p.m., Allen Pais wrote:
> alloc_workqueue is not checked for errors and as a result,
> a potential NULL dereference could occur.
>
> Signed-off-by: Allen Pais <allen.pais@oracle.com>
> ---
> drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
> index c56ac47..caa82a8 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
> @@ -62,6 +62,11 @@ int kfd_interrupt_init(struct kfd_dev *kfd)
> }
>
> kfd->ih_wq = alloc_workqueue("KFD IH", WQ_HIGHPRI, 1);
> + if (unlikely(!kfd->ih_wq)) {
> + fifo_free(&kfd->ih_fifo);

This does not compile. I think this should be kfifo_free.

> + dev_err(kfd_chardev(), "Failed to allocate KFD IH workqueue\n");
> + return kfd->ih_wq;

This throws a compiler warning "return makes integer from pointer
without a cast". What's worse, kfd->ih_wq is NULL here and
kfd_interrupt_init returns 0 to mean success, so returning a NULL
pointer is definitely not what you want here. This function should
return a negative error code on failure. I propose -ENOMEM.

I'm going to apply your patch with those fixes.

Regards,
  Felix


> + }
> spin_lock_init(&kfd->interrupt_lock);
>
> INIT_WORK(&kfd->interrupt_work, interrupt_wq);
\
 
 \ /
  Last update: 2019-09-19 22:39    [W:0.066 / U:0.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site