From: Tom Rix trix@redhat.com
commit 41855a898650803e24b284173354cc3e44d07725 upstream.
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 trix@redhat.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/radeon/ci_dpm.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/radeon/ci_dpm.c +++ b/drivers/gpu/drm/radeon/ci_dpm.c @@ -5554,6 +5554,7 @@ static int ci_parse_power_table(struct r 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; @@ -5563,10 +5564,8 @@ static int ci_parse_power_table(struct r 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, @@ -5588,8 +5587,8 @@ static int ci_parse_power_table(struct r 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++) {