lkml.org 
[lkml]   [2019]   [Jun]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] drm/amd/pp: fix a dereference of a pointer before it is null checked
Date
From: Colin Ian King <colin.king@canonical.com>

The pointer hwmgr is dereferenced when initializing pointer adev however
it is a little later hwmgr is null checked, implying it could potentially
be null hence the assignment of adev may cause a null pointer dereference.
Fix this by moving the assignment after the null check. Note that I did
think of removing adev as it is only used once, however, hwmgr->adev is
a void * pointer, so using adev avoids some ugly casting so it makes sense
to still use it.

Addresses-Coverity: ("Dereference before null check")
Fixes: 59156faf810e ("drm/amd/pp: Remove the cgs wrapper for notify smu version on APU")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
drivers/gpu/drm/amd/powerplay/smumgr/smu8_smumgr.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/powerplay/smumgr/smu8_smumgr.c b/drivers/gpu/drm/amd/powerplay/smumgr/smu8_smumgr.c
index 8189fe402c6d..12815b3830e4 100644
--- a/drivers/gpu/drm/amd/powerplay/smumgr/smu8_smumgr.c
+++ b/drivers/gpu/drm/amd/powerplay/smumgr/smu8_smumgr.c
@@ -722,13 +722,11 @@ static int smu8_request_smu_load_fw(struct pp_hwmgr *hwmgr)

static int smu8_start_smu(struct pp_hwmgr *hwmgr)
{
- struct amdgpu_device *adev = hwmgr->adev;
-
+ struct amdgpu_device *adev;
uint32_t index = SMN_MP1_SRAM_START_ADDR +
SMU8_FIRMWARE_HEADER_LOCATION +
offsetof(struct SMU8_Firmware_Header, Version);

-
if (hwmgr == NULL || hwmgr->device == NULL)
return -EINVAL;

@@ -738,6 +736,7 @@ static int smu8_start_smu(struct pp_hwmgr *hwmgr)
((hwmgr->smu_version >> 16) & 0xFF),
((hwmgr->smu_version >> 8) & 0xFF),
(hwmgr->smu_version & 0xFF));
+ adev = hwmgr->adev;
adev->pm.fw_version = hwmgr->smu_version >> 8;

return smu8_request_smu_load_fw(hwmgr);
--
2.20.1
\
 
 \ /
  Last update: 2019-06-29 15:56    [W:0.032 / U:0.776 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site