platform/x86/intel/tpmi: Fix double free reported by Smatch

Fix warning:
drivers/platform/x86/intel/tpmi.c:253 tpmi_create_device()
	warn: 'feature_vsec_dev' was already freed.

If there is some error, feature_vsec_dev memory is freed as part
of resource managed call intel_vsec_add_aux(). So, additional
kfree() call is not required.

Reordered res allocation and feature_vsec_dev, so that on error
only res is freed.

Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/platform-driver-x86/Y%2FxYR7WGiPayZu%2FR@kili/T/#u
Fixes: 47731fd2865f ("platform/x86/intel: Intel TPMI enumeration driver")
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20230227140614.2913474-1-srinivas.pandruvada@linux.intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/platform/x86/intel/tpmi.c b/drivers/platform/x86/intel/tpmi.c
index c60733261c89c9cf106088814126aca6cb70f438..c999732b0f1e5d3faf8c74bac78829efb82a14e1 100644 (file)
--- a/drivers/platform/x86/intel/tpmi.c
+++ b/drivers/platform/x86/intel/tpmi.c
@@ -209,14 +209,14 @@ static int tpmi_create_device(struct intel_tpmi_info *tpmi_info,
        if (!name)
                return -EOPNOTSUPP;
 
-       feature_vsec_dev = kzalloc(sizeof(*feature_vsec_dev), GFP_KERNEL);
-       if (!feature_vsec_dev)
+       res = kcalloc(pfs->pfs_header.num_entries, sizeof(*res), GFP_KERNEL);
+       if (!res)
                return -ENOMEM;
 
-       res = kcalloc(pfs->pfs_header.num_entries, sizeof(*res), GFP_KERNEL);
-       if (!res) {
+       feature_vsec_dev = kzalloc(sizeof(*feature_vsec_dev), GFP_KERNEL);
+       if (!feature_vsec_dev) {
                ret = -ENOMEM;
-               goto free_vsec;
+               goto free_res;
        }
 
        snprintf(feature_id_name, sizeof(feature_id_name), "tpmi-%s", name);
@@ -239,6 +239,8 @@ static int tpmi_create_device(struct intel_tpmi_info *tpmi_info,
        /*
         * intel_vsec_add_aux() is resource managed, no explicit
         * delete is required on error or on module unload.
+        * feature_vsec_dev memory is also freed as part of device
+        * delete.
         */
        ret = intel_vsec_add_aux(vsec_dev->pcidev, &vsec_dev->auxdev.dev,
                                 feature_vsec_dev, feature_id_name);
@@ -249,8 +251,6 @@ static int tpmi_create_device(struct intel_tpmi_info *tpmi_info,
 
 free_res:
        kfree(res);
-free_vsec:
-       kfree(feature_vsec_dev);
 
        return ret;
 }