From 99010fac8b8c1e4f8663cb8b55c1a6584f3b84ba Mon Sep 17 00:00:00 2001 From: Tom Rix Date: Mon, 6 Jul 2020 05:28:57 -0700 Subject: [PATCH] drm/radeon: fix double free 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 Signed-off-by: Alex Deucher --- 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++) {