clang-tidy: fix bugprone-not-null-terminated-result

Fixes: tpm2-software#2826

Signed-off-by: Johannes Holland <johannes.holland@infineon.de>

.clang-tidy

@@ -9,8 +9,6 @@
 #   [TODO]
 # -bugprone-narrowing-conversions
 #   [TODO]
-# -bugprone-not-null-terminated-result
-#   [TODO]
 #
 # -clang-analyzer-optin.performance.Padding
 #   We prefer logical/semantic order over (potentially insignificant)
@@ -28,7 +26,6 @@ Checks: "\
   -bugprone-easily-swappable-parameters, \
   -bugprone-implicit-widening-of-multiplication-result, \
   -bugprone-narrowing-conversions, \
-  -bugprone-not-null-terminated-result, \
   \
   clang-analyzer, \
   -clang-analyzer-optin.performance.Padding, \

src/tss2-policy/tss2_policy.c

@@ -415,7 +415,8 @@ Tss2_PolicyGetDescription(
             policy_ctx->path);
 
     const char *description = policy_ctx->policy.description;
-    size_t len = strlen(description);
+    /* length including null termination */
+    size_t len = strlen(description) + 1;
 
     /* NULL buffer let calller know size */
     if (!buffer) {
@@ -429,9 +430,9 @@ Tss2_PolicyGetDescription(
         return_if_error(TSS2_POLICY_RC_BUFFER_TOO_SMALL, "Specified buffer is too small");
     }
 
-    /* all is well, copy it to user and let them know size */
+    /* all is well, copy it to user (including null termination) and let them know size */
     *size = len;
-    memcpy(buffer, description, len);
+    strcpy(buffer, description);
 
     LOG_TRACE("finished, returning: 0x0");
     return TSS2_RC_SUCCESS;