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 --- 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;