From: Colin Ian King Date: Wed, 29 May 2019 15:07:34 +0000 (+0100) Subject: drm/amdkfd: fix null pointer dereference on dev X-Git-Tag: v5.15~5873^2~28^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=cf401e2856b27b2deeada498eab864e2a50cf219;p=platform%2Fkernel%2Flinux-starfive.git drm/amdkfd: fix null pointer dereference on dev The pointer dev is set to null yet it is being dereferenced when checking dev->dqm->sched_policy. Fix this by performing the check on dev->dqm->sched_policy after dev has been assigned and null checked. Also remove the redundant null assignment to dev. Addresses-Coverity: ("Explicit null dereference") Fixes: 1a058c337676 ("drm/amdkfd: New IOCTL to allocate queue GWS") Signed-off-by: Colin Ian King Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c index aab2aa6..ea82828 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c @@ -1572,10 +1572,9 @@ static int kfd_ioctl_alloc_queue_gws(struct file *filep, { int retval; struct kfd_ioctl_alloc_queue_gws_args *args = data; - struct kfd_dev *dev = NULL; + struct kfd_dev *dev; - if (!hws_gws_support || - dev->dqm->sched_policy == KFD_SCHED_POLICY_NO_HWS) + if (!hws_gws_support) return -EINVAL; dev = kfd_device_by_id(args->gpu_id); @@ -1583,6 +1582,8 @@ static int kfd_ioctl_alloc_queue_gws(struct file *filep, pr_debug("Could not find gpu id 0x%x\n", args->gpu_id); return -EINVAL; } + if (dev->dqm->sched_policy == KFD_SCHED_POLICY_NO_HWS) + return -EINVAL; mutex_lock(&p->mutex); retval = pqm_set_gws(&p->pqm, args->queue_id, args->num_gws ? dev->gws : NULL);