From e79a2398e1b2d47060474dca291542368183bc0f Mon Sep 17 00:00:00 2001
From: Lee Jones <lee.jones@linaro.org>
Date: Thu, 31 Mar 2022 13:21:17 +0100
Subject: [PATCH] drm/amdkfd: Create file descriptor after client is added to smi_clients list
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Git-commit: e79a2398e1b2d47060474dca291542368183bc0f
Patch-mainline: v5.18-rc2
References: git-fixes
This ensures userspace cannot prematurely clean-up the client before
it is fully initialised which has been proven to cause issues in the
past.
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c | 24 +++++++++++++--------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
index e4beebb1c80a..f2e1d506ba21 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
@@ -247,15 +247,6 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
return ret;
}
- ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
- O_RDWR);
- if (ret < 0) {
- kfifo_free(&client->fifo);
- kfree(client);
- return ret;
- }
- *fd = ret;
-
init_waitqueue_head(&client->wait_queue);
spin_lock_init(&client->lock);
client->events = 0;
@@ -265,5 +256,20 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
list_add_rcu(&client->list, &dev->smi_clients);
spin_unlock(&dev->smi_lock);
+ ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
+ O_RDWR);
+ if (ret < 0) {
+ spin_lock(&dev->smi_lock);
+ list_del_rcu(&client->list);
+ spin_unlock(&dev->smi_lock);
+
+ synchronize_rcu();
+
+ kfifo_free(&client->fifo);
+ kfree(client);
+ return ret;
+ }
+ *fd = ret;
+
return 0;
}
--
2.31.1