wpabuf: Add WPA_TRACE code to validate correct freeing of wpabuf

[libeap.git] / src / utils / wpabuf.c

diff --git a/src/utils/wpabuf.c b/src/utils/wpabuf.c
index 8181912..714034b 100644 (file)
--- a/src/utils/wpabuf.c
+++ b/src/utils/wpabuf.c
@@ -15,13 +15,37 @@
 #include "includes.h"
 
 #include "common.h"
+#include "trace.h"
 #include "wpabuf.h"
 
+#ifdef WPA_TRACE
+#define WPABUF_MAGIC 0x51a974e3
+
+struct wpabuf_trace {
+       unsigned int magic;
+};
+
+struct wpabuf_trace * wpabuf_get_trace(const struct wpabuf *buf)
+{
+       return (struct wpabuf_trace *)
+               ((const u8 *) buf - sizeof(struct wpabuf_trace));
+}
+#endif /* WPA_TRACE */
+
+
 static void wpabuf_overflow(const struct wpabuf *buf, size_t len)
 {
+#ifdef WPA_TRACE
+       struct wpabuf_trace *trace = wpabuf_get_trace(buf);
+       if (trace->magic != WPABUF_MAGIC) {
+               wpa_printf(MSG_ERROR, "wpabuf: invalid magic %x",
+                          trace->magic);
+       }
+#endif /* WPA_TRACE */
        wpa_printf(MSG_ERROR, "wpabuf %p (size=%lu used=%lu) overflow len=%lu",
                   buf, (unsigned long) buf->size, (unsigned long) buf->used,
                   (unsigned long) len);
+       wpa_trace_show("wpabuf overflow");
        abort();
 }
 
@@ -29,10 +53,25 @@ static void wpabuf_overflow(const struct wpabuf *buf, size_t len)
 int wpabuf_resize(struct wpabuf **_buf, size_t add_len)
 {
        struct wpabuf *buf = *_buf;
+#ifdef WPA_TRACE
+       struct wpabuf_trace *trace;
+#endif /* WPA_TRACE */
+
        if (buf == NULL) {
                *_buf = wpabuf_alloc(add_len);
                return *_buf == NULL ? -1 : 0;
        }
+
+#ifdef WPA_TRACE
+       trace = wpabuf_get_trace(buf);
+       if (trace->magic != WPABUF_MAGIC) {
+               wpa_printf(MSG_ERROR, "wpabuf: invalid magic %x",
+                          trace->magic);
+               wpa_trace_show("wpabuf_resize invalid magic");
+               abort();
+       }
+#endif /* WPA_TRACE */
+
        if (buf->used + add_len > buf->size) {
                unsigned char *nbuf;
                if (buf->ext_data) {
@@ -42,6 +81,18 @@ int wpabuf_resize(struct wpabuf **_buf, size_t add_len)
                        os_memset(nbuf + buf->used, 0, add_len);
                        buf->ext_data = nbuf;
                } else {
+#ifdef WPA_TRACE
+                       nbuf = os_realloc(trace, sizeof(struct wpabuf_trace) +
+                                         sizeof(struct wpabuf) +
+                                         buf->used + add_len);
+                       if (nbuf == NULL)
+                               return -1;
+                       trace = (struct wpabuf_trace *) nbuf;
+                       buf = (struct wpabuf *) (trace + 1);
+                       os_memset(nbuf + sizeof(struct wpabuf_trace) +
+                                 sizeof(struct wpabuf) + buf->used, 0,
+                                 add_len);
+#else /* WPA_TRACE */
                        nbuf = os_realloc(buf, sizeof(struct wpabuf) +
                                          buf->used + add_len);
                        if (nbuf == NULL)
@@ -49,6 +100,7 @@ int wpabuf_resize(struct wpabuf **_buf, size_t add_len)
                        buf = (struct wpabuf *) nbuf;
                        os_memset(nbuf + sizeof(struct wpabuf) + buf->used, 0,
                                  add_len);
+#endif /* WPA_TRACE */
                        *_buf = buf;
                }
                buf->size = buf->used + add_len;
@@ -65,9 +117,20 @@ int wpabuf_resize(struct wpabuf **_buf, size_t add_len)
  */
 struct wpabuf * wpabuf_alloc(size_t len)
 {
+#ifdef WPA_TRACE
+       struct wpabuf_trace *trace = os_zalloc(sizeof(struct wpabuf_trace) +
+                                              sizeof(struct wpabuf) + len);
+       struct wpabuf *buf;
+       if (trace == NULL)
+               return NULL;
+       trace->magic = WPABUF_MAGIC;
+       buf = (struct wpabuf *) (trace + 1);
+#else /* WPA_TRACE */
        struct wpabuf *buf = os_zalloc(sizeof(struct wpabuf) + len);
        if (buf == NULL)
                return NULL;
+#endif /* WPA_TRACE */
+
        buf->size = len;
        return buf;
 }
@@ -75,9 +138,19 @@ struct wpabuf * wpabuf_alloc(size_t len)
 
 struct wpabuf * wpabuf_alloc_ext_data(u8 *data, size_t len)
 {
+#ifdef WPA_TRACE
+       struct wpabuf_trace *trace = os_zalloc(sizeof(struct wpabuf_trace) +
+                                              sizeof(struct wpabuf));
+       struct wpabuf *buf;
+       if (trace == NULL)
+               return NULL;
+       trace->magic = WPABUF_MAGIC;
+       buf = (struct wpabuf *) (trace + 1);
+#else /* WPA_TRACE */
        struct wpabuf *buf = os_zalloc(sizeof(struct wpabuf));
        if (buf == NULL)
                return NULL;
+#endif /* WPA_TRACE */
 
        buf->size = len;
        buf->used = len;
@@ -111,10 +184,25 @@ struct wpabuf * wpabuf_dup(const struct wpabuf *src)
  */
 void wpabuf_free(struct wpabuf *buf)
 {
+#ifdef WPA_TRACE
+       struct wpabuf_trace *trace;
+       if (buf == NULL)
+               return;
+       trace = wpabuf_get_trace(buf);
+       if (trace->magic != WPABUF_MAGIC) {
+               wpa_printf(MSG_ERROR, "wpabuf_free: invalid magic %x",
+                          trace->magic);
+               wpa_trace_show("wpabuf_free magic mismatch");
+               abort();
+       }
+       os_free(buf->ext_data);
+       os_free(trace);
+#else /* WPA_TRACE */
        if (buf == NULL)
                return;
        os_free(buf->ext_data);
        os_free(buf);
+#endif /* WPA_TRACE */
 }