[PATCH v2] drm/msm: Fix submit error-path leaks

[Rob Clark <robdclark@gmail.com>]

From: Rob Clark <robdclark@chromium.org>

For errors after msm_submitqueue_get(), we need to drop the submitqueue
reference.  Additionally after get_unused_fd() we need to drop the fd.
The ordering for dropping the queue lock and put_unused_fd() is not
important, so just move this all into out_post_unlock.

v2: Only drop queue ref if submit doesn't take it

Reported-by: pinkperfect2021@gmail.com
Fixes: f0de40a131d9 drm/msm: ("Reorder lock vs submit alloc")
Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/msm_gem_submit.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 6c6aefaa72be..77d73a81d10e 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -767,27 +767,29 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	queue = msm_submitqueue_get(ctx, args->queueid);
 	if (!queue)
 		return -ENOENT;
 
 	ring = gpu->rb[queue->ring_nr];
 
 	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
 		out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
 		if (out_fence_fd < 0) {
 			ret = out_fence_fd;
-			return ret;
+			goto out_post_unlock;
 		}
 	}
 
 	submit = submit_create(dev, gpu, queue, args->nr_bos, args->nr_cmds);
-	if (IS_ERR(submit))
-		return PTR_ERR(submit);
+	if (IS_ERR(submit)) {
+		ret = PTR_ERR(submit);
+		goto out_post_unlock;
+	}
 
 	trace_msm_gpu_submit(pid_nr(submit->pid), ring->id, submit->ident,
 		args->nr_bos, args->nr_cmds);
 
 	ret = mutex_lock_interruptible(&queue->lock);
 	if (ret)
 		goto out_post_unlock;
 
 	if (args->flags & MSM_SUBMIT_SUDO)
 		submit->in_rb = true;
@@ -962,25 +964,33 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	msm_reset_syncobjs(syncobjs_to_reset, args->nr_in_syncobjs);
 	msm_process_post_deps(post_deps, args->nr_out_syncobjs,
 	                      submit->user_fence);
 
 
 out:
 	submit_cleanup(submit, !!ret);
 	if (has_ww_ticket)
 		ww_acquire_fini(&submit->ticket);
 out_unlock:
-	if (ret && (out_fence_fd >= 0))
-		put_unused_fd(out_fence_fd);
 	mutex_unlock(&queue->lock);
 out_post_unlock:
-	msm_gem_submit_put(submit);
+	if (ret && (out_fence_fd >= 0))
+		put_unused_fd(out_fence_fd);
+	if (submit) {
+		msm_gem_submit_put(submit);
+	} else {
+		/*
+		 * If the submit hasn't yet taken ownership of the queue
+		 * then we need to drop the reference ourself:
+		 */
+		msm_submitqueue_put(queue);
+	}
 	if (!IS_ERR_OR_NULL(post_deps)) {
 		for (i = 0; i < args->nr_out_syncobjs; ++i) {
 			kfree(post_deps[i].chain);
 			drm_syncobj_put(post_deps[i].syncobj);
 		}
 		kfree(post_deps);
 	}
 
 	if (!IS_ERR_OR_NULL(syncobjs_to_reset)) {
 		for (i = 0; i < args->nr_in_syncobjs; ++i) {
-- 
2.39.2