Commit 5b1834d6 authored by Tvrtko Ursulin's avatar Tvrtko Ursulin Committed by Christian König
Browse files

drm/fdinfo: Protect against driver unbind 



If we unbind a driver from the PCI device with an active DRM client,
subsequent read of the fdinfo data associated with the file descriptor in
question will not end well.

Protect the path with a drm_dev_enter/exit() pair.

Signed-off-by: default avatarTvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Fixes: 3f09a0cd ("drm: Add common fdinfo helper")
Cc: <stable@vger.kernel.org> # v6.5+
Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20250418162512.72324-1-tvrtko.ursulin@igalia.com
parent 76047483

drivers/gpu/drm/drm_file.c

+6 −0
Original line number Diff line number Diff line
@@ -964,6 +964,10 @@ void drm_show_fdinfo(struct seq_file *m, struct file *f) 
	struct drm_file *file = f->private_data;

	struct drm_device *dev = file->minor->dev;

	struct drm_printer p = drm_seq_file_printer(m);

	int idx;



	if (!drm_dev_enter(dev, &idx))

		return;



	drm_printf(&p, "drm-driver:\t%s\n", dev->driver->name);

	drm_printf(&p, "drm-client-id:\t%llu\n", file->client_id);
@@ -983,6 +987,8 @@ void drm_show_fdinfo(struct seq_file *m, struct file *f) 


	if (dev->driver->show_fdinfo)

		dev->driver->show_fdinfo(&p, file);



	drm_dev_exit(idx);

}

EXPORT_SYMBOL(drm_show_fdinfo);