[PATCH AUTOSEL 4.19 01/10] drm/amd/display: Fix potential null-deref in dm_resume

[PATCH AUTOSEL 4.19 01/10] drm/amd/display: Fix potential null-deref in dm_resume

[Sasha Levin]

From: Roman Li <roman.li@amd.com>

[ Upstream commit 7a7175a2cd84b7874bebbf8e59f134557a34161b ]

[Why]
Fixing smatch error:
dm_resume() error: we previously assumed 'aconnector->dc_link' could be null

[How]
Check if dc_link null at the beginning of the loop,
so further checks can be dropped.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

Reviewed-by: Wayne Lin <Wayne.Lin@amd.com>
Acked-by: Jasdeep Dhillon <jdhillon@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 57678e6dcdc4c..98d51bc204172 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -773,12 +773,14 @@ static int dm_resume(void *handle)
 	list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
 		aconnector = to_amdgpu_dm_connector(connector);
 
+		if (!aconnector->dc_link)
+			continue;
+
 		/*
 		 * this is the case when traversing through already created
 		 * MST connectors, should be skipped
 		 */
-		if (aconnector->dc_link &&
-		    aconnector->dc_link->type == dc_connection_mst_branch)
+		if (aconnector->dc_link->type == dc_connection_mst_branch)
 			continue;
 
 		mutex_lock(&aconnector->hpd_lock);
-- 
2.39.0

[PATCH AUTOSEL 4.19 02/10] drm/radeon: free iio for atombios when driver shutdown

[Sasha Levin]

From: Liwei Song <liwei.song@windriver.com>

[ Upstream commit 4773fadedca918faec443daaca5e4ea1c0ced144 ]

Fix below kmemleak when unload radeon driver:

unreferenced object 0xffff9f8608ede200 (size 512):
  comm "systemd-udevd", pid 326, jiffies 4294682822 (age 716.338s)
  hex dump (first 32 bytes):
    00 00 00 00 c4 aa ec aa 14 ab 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000062fadebe>] kmem_cache_alloc_trace+0x2f1/0x500
    [<00000000b6883cea>] atom_parse+0x117/0x230 [radeon]
    [<00000000158c23fd>] radeon_atombios_init+0xab/0x170 [radeon]
    [<00000000683f672e>] si_init+0x57/0x750 [radeon]
    [<00000000566cc31f>] radeon_device_init+0x559/0x9c0 [radeon]
    [<0000000046efabb3>] radeon_driver_load_kms+0xc1/0x1a0 [radeon]
    [<00000000b5155064>] drm_dev_register+0xdd/0x1d0
    [<0000000045fec835>] radeon_pci_probe+0xbd/0x100 [radeon]
    [<00000000e69ecca3>] pci_device_probe+0xe1/0x160
    [<0000000019484b76>] really_probe.part.0+0xc1/0x2c0
    [<000000003f2649da>] __driver_probe_device+0x96/0x130
    [<00000000231c5bb1>] driver_probe_device+0x24/0xf0
    [<0000000000a42377>] __driver_attach+0x77/0x190
    [<00000000d7574da6>] bus_for_each_dev+0x7f/0xd0
    [<00000000633166d2>] driver_attach+0x1e/0x30
    [<00000000313b05b8>] bus_add_driver+0x12c/0x1e0

iio was allocated in atom_index_iio() called by atom_parse(),
but it doesn't got released when the dirver is shutdown.
Fix this kmemleak by free it in radeon_atombios_fini().

Signed-off-by: Liwei Song <liwei.song@windriver.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/radeon/radeon_device.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index cc1c07963116c..bcca0dd67fd15 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1015,6 +1015,7 @@ void radeon_atombios_fini(struct radeon_device *rdev)
 {
 	if (rdev->mode_info.atom_context) {
 		kfree(rdev->mode_info.atom_context->scratch);
+		kfree(rdev->mode_info.atom_context->iio);
 	}
 	kfree(rdev->mode_info.atom_context);
 	rdev->mode_info.atom_context = NULL;
-- 
2.39.0