[PATCH 4.19 41/74] drm/nouveau: fix memory leak in nouveau_conn_reset()

Greg Kroah-Hartman
2019-08-05T13:10:28Z

[ Upstream commit 09b90e2fe35faeace2488234e2a7728f2ea8ba26 ]

In nouveau_conn_reset(), if connector->state is true,
__drm_atomic_helper_connector_destroy_state() will be called,
but the memory pointed by asyc isn't freed. Memory leak happens
in the following function __drm_atomic_helper_connector_reset(),
where newly allocated asyc->state will be assigned to connector->state.

So using nouveau_conn_atomic_destroy_state() instead of
__drm_atomic_helper_connector_destroy_state to free the "old" asyc.

Here the is the log showing memory leak.

unreferenced object 0xffff8c5480483c80 (size 192):
comm "kworker/0:2", pid 188, jiffies 4294695279 (age 53.179s)
hex dump (first 32 bytes):
00 f0 ba 7b 54 8c ff ff 00 00 00 00 00 00 00 00 ...{T...........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000005005c0d0>] kmem_cache_alloc_trace+0x195/0x2c0
[<00000000a122baed>] nouveau_conn_reset+0x25/0xc0 [nouveau]
[<000000004fd189a2>] nouveau_connector_create+0x3a7/0x610 [nouveau]
[<00000000c73343a8>] nv50_display_create+0x343/0x980 [nouveau]
[<000000002e2b03c3>] nouveau_display_create+0x51f/0x660 [nouveau]
[<00000000c924699b>] nouveau_drm_device_init+0x182/0x7f0 [nouveau]
[<00000000cc029436>] nouveau_drm_probe+0x20c/0x2c0 [nouveau]
[<000000007e961c3e>] local_pci_probe+0x47/0xa0
[<00000000da14d569>] work_for_cpu_fn+0x1a/0x30
[<0000000028da4805>] process_one_work+0x27c/0x660
[<000000001d415b04>] worker_thread+0x22b/0x3f0
[<0000000003b69f1f>] kthread+0x12f/0x150
[<00000000c94c29b7>] ret_from_fork+0x3a/0x50

Signed-off-by: Yongxin Liu <yongxin.liu@windriver.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/nouveau/nouveau_connector.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 247f72cc4d10a..fb0094fc55834 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -251,7 +251,7 @@ nouveau_conn_reset(struct drm_connector *connector)
return;

if (connector->state)
- __drm_atomic_helper_connector_destroy_state(connector->state);
+ nouveau_conn_atomic_destroy_state(connector, connector->state);
__drm_atomic_helper_connector_reset(connector, &asyc->state);
asyc->dither.mode = DITHERING_MODE_AUTO;
asyc->dither.depth = DITHERING_DEPTH_AUTO;
--
2.20.1