xf86drm: Fix error path in drmGetDevice2

In drmGetDevice2 when no local device is found or when
drm_device_has_rdev filters out all devices, *device might be left
uninitialized causing drmGetDevice2 to not return error - since
it's only returned when *device == NULL.

Above leads to crash in the firefox in system with amdgpu.

With this change firefox displays:

libGL error: MESA-LOADER: failed to retrieve device information
libGL error: unable to load driver: amdgpu_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: amdgpu
libGL error: MESA-LOADER: failed to retrieve device information
libGL error: unable to load driver: amdgpu_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: amdgpu

and doesn't crash.

Bugzilla: https://bugs.freedesktop.org/107384
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Mariusz Ceier <mceier+mesa-dev@gmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/xf86drm.c b/xf86drm.c
index 1e621e99..336d64de 100644
--- a/xf86drm.c
+++ b/xf86drm.c
@@ -3935,6 +3935,8 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device)
 
     drmFoldDuplicatedDevices(local_devices, node_count);
 
+    *device = NULL;
+
     for (i = 0; i < node_count; i++) {
         if (!local_devices[i])
             continue;