From: Tom Rix <t...@redhat.com>

clang static analysis flags this error

drivers/gpu/drm/radeon/ci_dpm.c:5652:9: warning: Use of memory after it is 
freed [unix.Malloc]
                kfree(rdev->pm.dpm.ps[i].ps_priv);
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/radeon/ci_dpm.c:5654:2: warning: Attempt to free released 
memory [unix.Malloc]
        kfree(rdev->pm.dpm.ps);
        ^~~~~~~~~~~~~~~~~~~~~~

problem is reported in ci_dpm_fini, with these code blocks.

        for (i = 0; i < rdev->pm.dpm.num_ps; i++) {
                kfree(rdev->pm.dpm.ps[i].ps_priv);
        }
        kfree(rdev->pm.dpm.ps);

The first free happens in ci_parse_power_table where it cleans up locally
on a failure.  ci_dpm_fini also does a cleanup.

        ret = ci_parse_power_table(rdev);
        if (ret) {
                ci_dpm_fini(rdev);
                return ret;
        }

So remove the cleanup in ci_parse_power_table and
move the num_ps calculation to inside the loop so ci_dpm_fini
will know how many array elements to free.

Fixes: cc8dbbb4f62a ("drm/radeon: add dpm support for CI dGPUs (v2)")

Signed-off-by: Tom Rix <t...@redhat.com>
---
 drivers/gpu/drm/radeon/ci_dpm.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/radeon/ci_dpm.c b/drivers/gpu/drm/radeon/ci_dpm.c
index 86ac032275bb..ba20c6f03719 100644
--- a/drivers/gpu/drm/radeon/ci_dpm.c
+++ b/drivers/gpu/drm/radeon/ci_dpm.c
@@ -5563,6 +5563,7 @@ static int ci_parse_power_table(struct radeon_device 
*rdev)
        if (!rdev->pm.dpm.ps)
                return -ENOMEM;
        power_state_offset = (u8 *)state_array->states;
+       rdev->pm.dpm.num_ps = 0;
        for (i = 0; i < state_array->ucNumEntries; i++) {
                u8 *idx;
                power_state = (union pplib_power_state *)power_state_offset;
@@ -5572,10 +5573,8 @@ static int ci_parse_power_table(struct radeon_device 
*rdev)
                if (!rdev->pm.power_state[i].clock_info)
                        return -EINVAL;
                ps = kzalloc(sizeof(struct ci_ps), GFP_KERNEL);
-               if (ps == NULL) {
-                       kfree(rdev->pm.dpm.ps);
+               if (ps == NULL)
                        return -ENOMEM;
-               }
                rdev->pm.dpm.ps[i].ps_priv = ps;
                ci_parse_pplib_non_clock_info(rdev, &rdev->pm.dpm.ps[i],
                                              non_clock_info,
@@ -5597,8 +5596,8 @@ static int ci_parse_power_table(struct radeon_device 
*rdev)
                        k++;
                }
                power_state_offset += 2 + power_state->v2.ucNumDPMLevels;
+               rdev->pm.dpm.num_ps = i + 1;
        }
-       rdev->pm.dpm.num_ps = state_array->ucNumEntries;
 
        /* fill in the vce power states */
        for (i = 0; i < RADEON_MAX_VCE_LEVELS; i++) {
-- 
2.18.1

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