diff mbox series

drm/fdinfo: Protect against driver unbind

Message ID 20250418162512.72324-1-tvrtko.ursulin@igalia.com (mailing list archive)
State New
Headers show
Series drm/fdinfo: Protect against driver unbind | expand

Commit Message

Tvrtko Ursulin April 18, 2025, 4:25 p.m. UTC 
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: Tvrtko 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>
---
 drivers/gpu/drm/drm_file.c | 6 ++++++
 1 file changed, 6 insertions(+)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
index c299cd94d3f7..cf2463090d3a 100644
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -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);