From: <gregkh@linuxfoundation.org>
To: thellstrom@vmware.com, brianp@vmware.com, stable@vger.kernel.org,
syeh@vmware.com
Cc: <stable@vger.kernel.org>
Subject: FAILED: patch "[PATCH] drm/vmwgfx: Fix up user_dmabuf refcounting" failed to apply to 4.2-stable tree
Date: Sat, 17 Oct 2015 13:29:25 -0700 [thread overview]
Message-ID: <144511376511055@kroah.com> (raw)
The patch below does not apply to the 4.2-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 54c12bc374408faddbff75dbf1a6167c19af39c4 Mon Sep 17 00:00:00 2001
From: Thomas Hellstrom <thellstrom@vmware.com>
Date: Mon, 14 Sep 2015 01:13:11 -0700
Subject: [PATCH] drm/vmwgfx: Fix up user_dmabuf refcounting
If user space calls unreference on a user_dmabuf it will typically
kill the struct ttm_base_object member which is responsible for the
user-space visibility. However the dmabuf part may still be alive and
refcounted. In some situations, like for shared guest-backed surface
referencing/opening, the driver may try to reference the
struct ttm_base_object member again, causing an immediate kernel warning
and a later kernel NULL pointer dereference.
Fix this by always maintaining a reference on the struct
ttm_base_object member, in situations where it might subsequently be
referenced.
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index 8f40692cf48a..b60b41f95e74 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -631,7 +631,8 @@ extern int vmw_user_dmabuf_alloc(struct vmw_private *dev_priv,
uint32_t size,
bool shareable,
uint32_t *handle,
- struct vmw_dma_buffer **p_dma_buf);
+ struct vmw_dma_buffer **p_dma_buf,
+ struct ttm_base_object **p_base);
extern int vmw_user_dmabuf_reference(struct ttm_object_file *tfile,
struct vmw_dma_buffer *dma_buf,
uint32_t *handle);
@@ -645,7 +646,8 @@ extern uint32_t vmw_dmabuf_validate_node(struct ttm_buffer_object *bo,
uint32_t cur_validate_node);
extern void vmw_dmabuf_validate_clear(struct ttm_buffer_object *bo);
extern int vmw_user_dmabuf_lookup(struct ttm_object_file *tfile,
- uint32_t id, struct vmw_dma_buffer **out);
+ uint32_t id, struct vmw_dma_buffer **out,
+ struct ttm_base_object **base);
extern int vmw_stream_claim_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv);
extern int vmw_stream_unref_ioctl(struct drm_device *dev, void *data,
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index b56565457c96..5da5de0cb522 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -1236,7 +1236,8 @@ static int vmw_translate_mob_ptr(struct vmw_private *dev_priv,
struct vmw_relocation *reloc;
int ret;
- ret = vmw_user_dmabuf_lookup(sw_context->fp->tfile, handle, &vmw_bo);
+ ret = vmw_user_dmabuf_lookup(sw_context->fp->tfile, handle, &vmw_bo,
+ NULL);
if (unlikely(ret != 0)) {
DRM_ERROR("Could not find or use MOB buffer.\n");
ret = -EINVAL;
@@ -1296,7 +1297,8 @@ static int vmw_translate_guest_ptr(struct vmw_private *dev_priv,
struct vmw_relocation *reloc;
int ret;
- ret = vmw_user_dmabuf_lookup(sw_context->fp->tfile, handle, &vmw_bo);
+ ret = vmw_user_dmabuf_lookup(sw_context->fp->tfile, handle, &vmw_bo,
+ NULL);
if (unlikely(ret != 0)) {
DRM_ERROR("Could not find or use GMR region.\n");
ret = -EINVAL;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c b/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c
index 76069f093ccf..222c9c2123a1 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c
@@ -484,7 +484,7 @@ int vmw_overlay_ioctl(struct drm_device *dev, void *data,
goto out_unlock;
}
- ret = vmw_user_dmabuf_lookup(tfile, arg->handle, &buf);
+ ret = vmw_user_dmabuf_lookup(tfile, arg->handle, &buf, NULL);
if (ret)
goto out_unlock;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
index c1912f852b42..e57667ca7557 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
@@ -354,7 +354,7 @@ int vmw_user_lookup_handle(struct vmw_private *dev_priv,
}
*out_surf = NULL;
- ret = vmw_user_dmabuf_lookup(tfile, handle, out_buf);
+ ret = vmw_user_dmabuf_lookup(tfile, handle, out_buf, NULL);
return ret;
}
@@ -481,7 +481,8 @@ int vmw_user_dmabuf_alloc(struct vmw_private *dev_priv,
uint32_t size,
bool shareable,
uint32_t *handle,
- struct vmw_dma_buffer **p_dma_buf)
+ struct vmw_dma_buffer **p_dma_buf,
+ struct ttm_base_object **p_base)
{
struct vmw_user_dma_buffer *user_bo;
struct ttm_buffer_object *tmp;
@@ -515,6 +516,10 @@ int vmw_user_dmabuf_alloc(struct vmw_private *dev_priv,
}
*p_dma_buf = &user_bo->dma;
+ if (p_base) {
+ *p_base = &user_bo->prime.base;
+ kref_get(&(*p_base)->refcount);
+ }
*handle = user_bo->prime.base.hash.key;
out_no_base_object:
@@ -631,6 +636,7 @@ int vmw_user_dmabuf_synccpu_ioctl(struct drm_device *dev, void *data,
struct vmw_dma_buffer *dma_buf;
struct vmw_user_dma_buffer *user_bo;
struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
+ struct ttm_base_object *buffer_base;
int ret;
if ((arg->flags & (drm_vmw_synccpu_read | drm_vmw_synccpu_write)) == 0
@@ -643,7 +649,8 @@ int vmw_user_dmabuf_synccpu_ioctl(struct drm_device *dev, void *data,
switch (arg->op) {
case drm_vmw_synccpu_grab:
- ret = vmw_user_dmabuf_lookup(tfile, arg->handle, &dma_buf);
+ ret = vmw_user_dmabuf_lookup(tfile, arg->handle, &dma_buf,
+ &buffer_base);
if (unlikely(ret != 0))
return ret;
@@ -651,6 +658,7 @@ int vmw_user_dmabuf_synccpu_ioctl(struct drm_device *dev, void *data,
dma);
ret = vmw_user_dmabuf_synccpu_grab(user_bo, tfile, arg->flags);
vmw_dmabuf_unreference(&dma_buf);
+ ttm_base_object_unref(&buffer_base);
if (unlikely(ret != 0 && ret != -ERESTARTSYS &&
ret != -EBUSY)) {
DRM_ERROR("Failed synccpu grab on handle 0x%08x.\n",
@@ -692,7 +700,8 @@ int vmw_dmabuf_alloc_ioctl(struct drm_device *dev, void *data,
return ret;
ret = vmw_user_dmabuf_alloc(dev_priv, vmw_fpriv(file_priv)->tfile,
- req->size, false, &handle, &dma_buf);
+ req->size, false, &handle, &dma_buf,
+ NULL);
if (unlikely(ret != 0))
goto out_no_dmabuf;
@@ -721,7 +730,8 @@ int vmw_dmabuf_unref_ioctl(struct drm_device *dev, void *data,
}
int vmw_user_dmabuf_lookup(struct ttm_object_file *tfile,
- uint32_t handle, struct vmw_dma_buffer **out)
+ uint32_t handle, struct vmw_dma_buffer **out,
+ struct ttm_base_object **p_base)
{
struct vmw_user_dma_buffer *vmw_user_bo;
struct ttm_base_object *base;
@@ -743,7 +753,10 @@ int vmw_user_dmabuf_lookup(struct ttm_object_file *tfile,
vmw_user_bo = container_of(base, struct vmw_user_dma_buffer,
prime.base);
(void)ttm_bo_reference(&vmw_user_bo->dma.base);
- ttm_base_object_unref(&base);
+ if (p_base)
+ *p_base = base;
+ else
+ ttm_base_object_unref(&base);
*out = &vmw_user_bo->dma;
return 0;
@@ -1004,7 +1017,7 @@ int vmw_dumb_create(struct drm_file *file_priv,
ret = vmw_user_dmabuf_alloc(dev_priv, vmw_fpriv(file_priv)->tfile,
args->size, false, &args->handle,
- &dma_buf);
+ &dma_buf, NULL);
if (unlikely(ret != 0))
goto out_no_dmabuf;
@@ -1032,7 +1045,7 @@ int vmw_dumb_map_offset(struct drm_file *file_priv,
struct vmw_dma_buffer *out_buf;
int ret;
- ret = vmw_user_dmabuf_lookup(tfile, handle, &out_buf);
+ ret = vmw_user_dmabuf_lookup(tfile, handle, &out_buf, NULL);
if (ret != 0)
return -EINVAL;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
index bba1ee395478..fd47547b0234 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
@@ -855,7 +855,7 @@ static int vmw_shader_define(struct drm_device *dev, struct drm_file *file_priv,
if (buffer_handle != SVGA3D_INVALID_ID) {
ret = vmw_user_dmabuf_lookup(tfile, buffer_handle,
- &buffer);
+ &buffer, NULL);
if (unlikely(ret != 0)) {
DRM_ERROR("Could not find buffer for shader "
"creation.\n");
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
index 3361769842f4..64b50409fa07 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -46,6 +46,7 @@ struct vmw_user_surface {
struct vmw_surface srf;
uint32_t size;
struct drm_master *master;
+ struct ttm_base_object *backup_base;
};
/**
@@ -656,6 +657,7 @@ static void vmw_user_surface_base_release(struct ttm_base_object **p_base)
struct vmw_resource *res = &user_srf->srf.res;
*p_base = NULL;
+ ttm_base_object_unref(&user_srf->backup_base);
vmw_resource_unreference(&res);
}
@@ -851,7 +853,8 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
res->backup_size,
true,
&backup_handle,
- &res->backup);
+ &res->backup,
+ &user_srf->backup_base);
if (unlikely(ret != 0)) {
vmw_resource_unreference(&res);
goto out_unlock;
@@ -1321,7 +1324,8 @@ int vmw_gb_surface_define_ioctl(struct drm_device *dev, void *data,
if (req->buffer_handle != SVGA3D_INVALID_ID) {
ret = vmw_user_dmabuf_lookup(tfile, req->buffer_handle,
- &res->backup);
+ &res->backup,
+ &user_srf->backup_base);
if (ret == 0 && res->backup->base.num_pages * PAGE_SIZE <
res->backup_size) {
DRM_ERROR("Surface backup buffer is too small.\n");
@@ -1335,7 +1339,8 @@ int vmw_gb_surface_define_ioctl(struct drm_device *dev, void *data,
req->drm_surface_flags &
drm_vmw_surface_flag_shareable,
&backup_handle,
- &res->backup);
+ &res->backup,
+ &user_srf->backup_base);
if (unlikely(ret != 0)) {
vmw_resource_unreference(&res);
next reply other threads:[~2015-10-17 20:29 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-17 20:29 gregkh [this message]
2015-11-05 7:57 ` FAILED: patch "[PATCH] drm/vmwgfx: Fix up user_dmabuf refcounting" failed to apply to 4.2-stable tree Thomas Hellstrom
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=144511376511055@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=brianp@vmware.com \
--cc=stable@vger.kernel.org \
--cc=syeh@vmware.com \
--cc=thellstrom@vmware.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.