On 22/04/2025 10:20, Koenig, Christian wrote:
[AMD Official Use Only - AMD Internal Distribution Only]
Reviewed-by: Christian König <christian.koe...@amd.com>
Thanks!
I could also add:
Fixes: 3f09a0cd4ea3 ("drm: Add common fdinfo helper")
Cc: <sta...@vger.kernel.org> # v6.5+
With a disclaimer that the problem predates the common helper. Not sure
if it is worth it for such an edge case.
I was planning to merge to drm-misc-next, but if I add the stable tag it
would be drm-misc-fixes right?
Regards,
Tvrtko
________________________________________
Von: Tvrtko Ursulin <tvrtko.ursu...@igalia.com>
Gesendet: Freitag, 18. April 2025 18:25
An: dri-devel@lists.freedesktop.org
Cc: kernel-...@igalia.com; Tvrtko Ursulin; Koenig, Christian; Lucas De Marchi;
Rodrigo Vivi; Umesh Nerlige Ramappa
Betreff: [PATCH] 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: Tvrtko Ursulin <tvrtko.ursu...@igalia.com>
Cc: Christian König <christian.koe...@amd.com>
Cc: Lucas De Marchi <lucas.demar...@intel.com>
Cc: Rodrigo Vivi <rodrigo.v...@intel.com>
Cc: Umesh Nerlige Ramappa <umesh.nerlige.rama...@intel.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);
--
2.48.0
