dri-devel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Sasha Levin <sashal@kernel.org>,
	syzbot+e3372a2afe1e7ef04bc7@syzkaller.appspotmail.com,
	Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>,
	Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>,
	dri-devel@lists.freedesktop.org,
	Ezequiel Garcia <ezequiel@collabora.com>
Subject: [PATCH AUTOSEL 5.7 169/274] drm/vkms: Hold gem object while still in-use
Date: Mon,  8 Jun 2020 19:04:22 -0400	[thread overview]
Message-ID: <20200608230607.3361041-169-sashal@kernel.org> (raw)
In-Reply-To: <20200608230607.3361041-1-sashal@kernel.org>

From: Ezequiel Garcia <ezequiel@collabora.com>

[ Upstream commit 0ea2ea42b31abc1141f2fd3911f952a97d401fcb ]

We need to keep the reference to the drm_gem_object
until the last access by vkms_dumb_create.

Therefore, the put the object after it is used.

This fixes a use-after-free issue reported by syzbot.

While here, change vkms_gem_create() symbol to static.

Reported-and-tested-by: syzbot+e3372a2afe1e7ef04bc7@syzkaller.appspotmail.com
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200427214405.13069-1-ezequiel@collabora.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/vkms/vkms_drv.h |  5 -----
 drivers/gpu/drm/vkms/vkms_gem.c | 11 ++++++-----
 2 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index eda04ffba7b1..f4036bb0b9a8 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -117,11 +117,6 @@ struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev,
 				  enum drm_plane_type type, int index);
 
 /* Gem stuff */
-struct drm_gem_object *vkms_gem_create(struct drm_device *dev,
-				       struct drm_file *file,
-				       u32 *handle,
-				       u64 size);
-
 vm_fault_t vkms_gem_fault(struct vm_fault *vmf);
 
 int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
diff --git a/drivers/gpu/drm/vkms/vkms_gem.c b/drivers/gpu/drm/vkms/vkms_gem.c
index 2e01186fb943..c541fec57566 100644
--- a/drivers/gpu/drm/vkms/vkms_gem.c
+++ b/drivers/gpu/drm/vkms/vkms_gem.c
@@ -97,10 +97,10 @@ vm_fault_t vkms_gem_fault(struct vm_fault *vmf)
 	return ret;
 }
 
-struct drm_gem_object *vkms_gem_create(struct drm_device *dev,
-				       struct drm_file *file,
-				       u32 *handle,
-				       u64 size)
+static struct drm_gem_object *vkms_gem_create(struct drm_device *dev,
+					      struct drm_file *file,
+					      u32 *handle,
+					      u64 size)
 {
 	struct vkms_gem_object *obj;
 	int ret;
@@ -113,7 +113,6 @@ struct drm_gem_object *vkms_gem_create(struct drm_device *dev,
 		return ERR_CAST(obj);
 
 	ret = drm_gem_handle_create(file, &obj->gem, handle);
-	drm_gem_object_put_unlocked(&obj->gem);
 	if (ret)
 		return ERR_PTR(ret);
 
@@ -142,6 +141,8 @@ int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
 	args->size = gem_obj->size;
 	args->pitch = pitch;
 
+	drm_gem_object_put_unlocked(gem_obj);
+
 	DRM_DEBUG_DRIVER("Created object of size %lld\n", size);
 
 	return 0;
-- 
2.25.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

  parent reply	other threads:[~2020-06-08 23:09 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-08 23:01 [PATCH AUTOSEL 5.7 001/274] drm/amdgpu: fix and cleanup amdgpu_gem_object_close v4 Sasha Levin
2020-06-08 23:01 ` [PATCH AUTOSEL 5.7 006/274] drm: bridge: adv7511: Extend list of audio sample rates Sasha Levin
2020-06-08 23:01 ` [PATCH AUTOSEL 5.7 016/274] drm/amd/display: Force watermark value propagation Sasha Levin
2020-06-08 23:01 ` [PATCH AUTOSEL 5.7 017/274] drm/amd/display: fix virtual signal dsc setup Sasha Levin
2020-06-08 23:01 ` [PATCH AUTOSEL 5.7 019/274] drm/amdgpu: Init data to avoid oops while reading pp_num_states Sasha Levin
2020-06-08 23:01 ` [PATCH AUTOSEL 5.7 020/274] drm/bridge: panel: Return always an error pointer in drm_panel_bridge_add() Sasha Levin
2020-06-08 23:02 ` [PATCH AUTOSEL 5.7 046/274] drm: rcar-du: Set primary plane zpos immutably at initializing Sasha Levin
2020-06-08 23:02 ` [PATCH AUTOSEL 5.7 060/274] drm/dp: Lenovo X13 Yoga OLED panel brightness fix Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 087/274] staging: android: ion: use vmap instead of vm_map_ram Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 090/274] drm/hisilicon: Enforce 128-byte stride alignment to fix the hardware limitation Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 095/274] drm/amd/display: Revert to old formula in set_vtg_params Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 104/274] drm/ast: Allocate initial CRTC state of the correct size Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 105/274] dt-bindings: display: mediatek: control dpi pins mode to avoid leakage Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 106/274] drm/mediatek: set dpi pin mode to gpio low to avoid leakage current Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 116/274] drm/amd/display: Correct updating logic of dcn21's pipe VM flags Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 117/274] drm/amd/display: dmcu wait loop calculation is incorrect in RV Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 127/274] drm/amd/display: Do not disable pipe split if mode is not supported Sasha Levin
2020-06-08 23:03 ` [PATCH AUTOSEL 5.7 138/274] drm/bridge: fix stack usage warning on old gcc Sasha Levin
2020-06-08 23:04 ` Sasha Levin [this message]
2020-06-08 23:04 ` [PATCH AUTOSEL 5.7 188/274] drm/mcde: dsi: Fix return value check in mcde_dsi_bind() Sasha Levin
2020-06-08 23:05 ` [PATCH AUTOSEL 5.7 223/274] drm/amd/powerpay: Disable gfxoff when setting manual mode on picasso and raven Sasha Levin
2020-06-08 23:05 ` [PATCH AUTOSEL 5.7 224/274] drm/amdgpu: Sync with VM root BO when switching VM to CPU update mode Sasha Levin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200608230607.3361041-169-sashal@kernel.org \
    --to=sashal@kernel.org \
    --cc=Rodrigo.Siqueira@amd.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=ezequiel@collabora.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rodrigosiqueiramelo@gmail.com \
    --cc=stable@vger.kernel.org \
    --cc=syzbot+e3372a2afe1e7ef04bc7@syzkaller.appspotmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox