Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966359AbbKFTlc (ORCPT ); Fri, 6 Nov 2015 14:41:32 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:47919 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031469AbbKFTco (ORCPT ); Fri, 6 Nov 2015 14:32:44 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Hellstrom , Brian Paul , Sinclair Yeh Subject: [PATCH 4.1 80/86] drm/vmwgfx: Fix up user_dmabuf refcounting Date: Fri, 6 Nov 2015 11:23:19 -0800 Message-Id: <20151106192209.259956179@linuxfoundation.org> X-Mailer: git-send-email 2.6.2 In-Reply-To: <20151106192205.351595349@linuxfoundation.org> References: <20151106192205.351595349@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9558 Lines: 277 4.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Hellstrom commit 54c12bc374408faddbff75dbf1a6167c19af39c4 upstream. 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. Signed-off-by: Thomas Hellstrom Reviewed-by: Brian Paul Reviewed-by: Sinclair Yeh Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 3 +++ drivers/gpu/drm/vmwgfx/vmwgfx_drv.h | 6 ++++-- drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 6 ++++-- drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c | 2 +- drivers/gpu/drm/vmwgfx/vmwgfx_resource.c | 29 +++++++++++++++++++++-------- drivers/gpu/drm/vmwgfx/vmwgfx_shader.c | 2 +- drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 12 +++++++++--- 7 files changed, 43 insertions(+), 17 deletions(-) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c @@ -1458,6 +1458,9 @@ static void __exit vmwgfx_exit(void) drm_pci_exit(&driver, &vmw_pci_driver); } +MODULE_INFO(vmw_patch, "ed7d78b2"); +MODULE_INFO(vmw_patch, "54c12bc3"); + module_init(vmwgfx_init); module_exit(vmwgfx_exit); --- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h @@ -636,7 +636,8 @@ extern int vmw_user_dmabuf_alloc(struct 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); @@ -650,7 +651,8 @@ extern uint32_t vmw_dmabuf_validate_node 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, --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c @@ -887,7 +887,8 @@ static int vmw_translate_mob_ptr(struct 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; @@ -949,7 +950,8 @@ static int vmw_translate_guest_ptr(struc 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; --- 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 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; --- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c @@ -356,7 +356,7 @@ int vmw_user_lookup_handle(struct vmw_pr } *out_surf = NULL; - ret = vmw_user_dmabuf_lookup(tfile, handle, out_buf); + ret = vmw_user_dmabuf_lookup(tfile, handle, out_buf, NULL); return ret; } @@ -483,7 +483,8 @@ int vmw_user_dmabuf_alloc(struct vmw_pri 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; @@ -517,6 +518,10 @@ int vmw_user_dmabuf_alloc(struct vmw_pri } *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: @@ -633,6 +638,7 @@ int vmw_user_dmabuf_synccpu_ioctl(struct 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 @@ -645,7 +651,8 @@ int vmw_user_dmabuf_synccpu_ioctl(struct 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; @@ -653,6 +660,7 @@ int vmw_user_dmabuf_synccpu_ioctl(struct 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", @@ -694,7 +702,8 @@ int vmw_dmabuf_alloc_ioctl(struct drm_de 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; @@ -723,7 +732,8 @@ int vmw_dmabuf_unref_ioctl(struct drm_de } 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; @@ -745,7 +755,10 @@ int vmw_user_dmabuf_lookup(struct ttm_ob 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; @@ -1006,7 +1019,7 @@ int vmw_dumb_create(struct drm_file *fil 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; @@ -1034,7 +1047,7 @@ int vmw_dumb_map_offset(struct drm_file 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; --- a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c @@ -470,7 +470,7 @@ int vmw_shader_define_ioctl(struct drm_d if (arg->buffer_handle != SVGA3D_INVALID_ID) { ret = vmw_user_dmabuf_lookup(tfile, arg->buffer_handle, - &buffer); + &buffer, NULL); if (unlikely(ret != 0)) { DRM_ERROR("Could not find buffer for shader " "creation.\n"); --- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c @@ -43,6 +43,7 @@ struct vmw_user_surface { struct vmw_surface srf; uint32_t size; struct drm_master *master; + struct ttm_base_object *backup_base; }; /** @@ -652,6 +653,8 @@ static void vmw_user_surface_base_releas struct vmw_resource *res = &user_srf->srf.res; *p_base = NULL; + if (user_srf->backup_base) + ttm_base_object_unref(&user_srf->backup_base); vmw_resource_unreference(&res); } @@ -846,7 +849,8 @@ int vmw_surface_define_ioctl(struct drm_ 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; @@ -1309,7 +1313,8 @@ int vmw_gb_surface_define_ioctl(struct d if (req->buffer_handle != SVGA3D_INVALID_ID) { ret = vmw_user_dmabuf_lookup(tfile, req->buffer_handle, - &res->backup); + &res->backup, + &user_srf->backup_base); } else if (req->drm_surface_flags & drm_vmw_surface_flag_create_buffer) ret = vmw_user_dmabuf_alloc(dev_priv, tfile, @@ -1317,7 +1322,8 @@ int vmw_gb_surface_define_ioctl(struct d 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); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/