• Tom Rix's avatar
    drm/radeon: fix double free · 41855a89
    Tom Rix authored
    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: cc8dbbb4 ("drm/radeon: add dpm support for CI dGPUs (v2)")
    Signed-off-by: default avatarTom Rix <trix@redhat.com>
    Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
    Cc: stable@vger.kernel.org
    41855a89
ci_dpm.c 174 KB