From cddef42a669e571d79b791ccbfdd75e32ef1a98e Mon Sep 17 00:00:00 2001 From: Daniel Thompson Date: Tue, 22 Dec 2015 19:36:44 -0200 Subject: [PATCH] drm: prime: Honour O_RDWR during prime-handle-to-fd MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Currently DRM_IOCTL_PRIME_HANDLE_TO_FD rejects all flags except (DRM|O)_CLOEXEC making it difficult (maybe impossible) for userspace to mmap() the resulting dma-buf even when this is supported by the DRM driver. It is trivial to relax the restriction and permit read/write access. This is safe because the flags are seldom touched by drm; mostly they are passed verbatim to dma_buf calls. v3 (Tiago): removed unused flags variable from drm_prime_handle_to_fd_ioctl. Reviewed-by: Chris Wilson Signed-off-by: Daniel Thompson Signed-off-by: Tiago Vignatti Reviewed-by: Stéphane Marchesin Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1450820214-12509-2-git-send-email-tiago.vignatti@intel.com [jy0922.shim: applied from mainline kernel] Signed-off-by: Joonyoung Shim Change-Id: I7e605e4e4fb10816e143a478ca0dc2aa018486f3 --- drivers/gpu/drm/drm_prime.c | 10 +++------- include/uapi/drm/drm.h | 1 + 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 7fec191..384e883 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 implementation 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. @@ -630,7 +630,6 @@ int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_prime_handle *args = data; - uint32_t flags; if (!drm_core_check_feature(dev, DRIVER_PRIME)) return -EINVAL; @@ -639,14 +638,11 @@ 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 ff6ef62..092fe3f 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -668,6 +668,7 @@ struct drm_set_client_cap { __u64 value; }; +#define DRM_RDWR O_RDWR #define DRM_CLOEXEC O_CLOEXEC struct drm_prime_handle { __u32 handle; -- 2.7.4