From 5b1834d6202f86180e451ad1a2a8a193a1da18fc Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Fri, 18 Apr 2025 17:25:12 +0100 Subject: [PATCH 3386/5403] drm/fdinfo: Protect against driver unbind MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Cc: Christian König Cc: Lucas De Marchi Cc: Rodrigo Vivi Cc: Umesh Nerlige Ramappa Reviewed-by: Christian König Fixes: 3f09a0cd4ea3 ("drm: Add common fdinfo helper") Cc: # v6.5+ Signed-off-by: Christian König Link: https://lore.kernel.org/r/20250418162512.72324-1-tvrtko.ursulin@igalia.com --- drivers/gpu/drm/drm_file.c | 6 ++++++ 1 file changed, 6 insertions(+) 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); -- 2.54.0