Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753141AbaKLOlf (ORCPT ); Wed, 12 Nov 2014 09:41:35 -0500 Received: from mail-ig0-f182.google.com ([209.85.213.182]:50134 "EHLO mail-ig0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752970AbaKLOld (ORCPT ); Wed, 12 Nov 2014 09:41:33 -0500 MIME-Version: 1.0 In-Reply-To: <1415792295-2466-2-git-send-email-daniel.thompson@linaro.org> References: <1415639805-17477-1-git-send-email-daniel.thompson@linaro.org> <1415792295-2466-1-git-send-email-daniel.thompson@linaro.org> <1415792295-2466-2-git-send-email-daniel.thompson@linaro.org> Date: Wed, 12 Nov 2014 09:41:32 -0500 Message-ID: Subject: Re: [PATCH v2 v3.18-rc4 1/4] drm: prime: Honour O_RDWR during prime-handle-to-fd From: Rob Clark To: Daniel Thompson Cc: David Airlie , "dri-devel@lists.freedesktop.org" , Benjamin Gaignard , Linux Kernel Mailing List , "patches@linaro.org" , linaro-kernel@lists.linaro.org, John Stultz , Sumit Semwal Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 12, 2014 at 6:38 AM, Daniel Thompson wrote: > Currently DRM_IOCTL_PRIME_HANDLE_TO_FD rejects all flags except > (DRM|O)_CLOEXEC making it hard for the userspace to generate a file > descriptor that can be used by mmap(). > > It is easy to relax the restriction and allow read/write permissions. > This should be safe because the flags are seldom touched by drm; mostly > they are passed verbatim to dma_buf calls. > > Signed-off-by: Daniel Thompson Reviewed-by: Rob Clark > --- > drivers/gpu/drm/drm_prime.c | 9 +++------ > include/uapi/drm/drm.h | 1 + > 2 files changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c > index 78ca30808422..8467b17c8053 100644 > --- a/drivers/gpu/drm/drm_prime.c > +++ b/drivers/gpu/drm/drm_prime.c > @@ -331,7 +331,7 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { > * drm_gem_prime_export - helper library implemention of the export callback > * @dev: drm_device to export from > * @obj: GEM object to export > - * @flags: flags like DRM_CLOEXEC > + * @flags: flags like DRM_CLOEXEC and DRM_RDWR > * > * This is the implementation of the gem_prime_export functions for GEM drivers > * using the PRIME helpers. > @@ -635,14 +635,11 @@ int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, > return -ENOSYS; > > /* check flags are valid */ > - if (args->flags & ~DRM_CLOEXEC) > + if (args->flags & ~(DRM_CLOEXEC | DRM_RDWR)) > return -EINVAL; > > - /* we only want to pass DRM_CLOEXEC which is == O_CLOEXEC */ > - flags = args->flags & DRM_CLOEXEC; > - > return dev->driver->prime_handle_to_fd(dev, file_priv, > - args->handle, flags, &args->fd); > + args->handle, args->flags, &args->fd); > } > > int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data, > diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h > index b0b855613641..89c2b68ddc51 100644 > --- a/include/uapi/drm/drm.h > +++ b/include/uapi/drm/drm.h > @@ -660,6 +660,7 @@ struct drm_set_client_cap { > __u64 value; > }; > > +#define DRM_RDWR O_RDWR > #define DRM_CLOEXEC O_CLOEXEC > struct drm_prime_handle { > __u32 handle; > -- > 1.9.3 > -- 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/