On Wed, Nov 12, 2014 at 6:38 AM, Daniel Thompson daniel.thompson@linaro.org 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 daniel.thompson@linaro.org
Reviewed-by: Rob Clark robdclark@gmail.com
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