gdb_server: fix memory leaks in users of get_reg_features_list()

v4:
- changed first line of commit message
v3:
- added extra LOG_ERROR() message
v2:
- Added missing "goto error"
- free also the on extra element of features[]

In contrast to target_get_gdb_reg_list(), the list returned by
get_reg_features_list() consists of items which are itself
malloc'ed.
--> Free the list items prior freeing the list itself.

Additionally:
- gdb_generate_target_description():
  o Do error handling similar as gdb_get_target_description_chunk() does.
- gdb_get_target_description_chunk()
  o **features must be initialised prior an "goto error" can happen

Change-Id: Iad07824618c51084e0aa0499ee6fc96198b320f0
Signed-off-by: Christian Eggers <ceggers@gmx.de>
Reviewed-on: http://openocd.zylin.com/1917
Tested-by: jenkins
Reviewed-by: Trevor Woerner <trevor.woerner@linaro.org>
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

diff --git a/src/server/gdb_server.c b/src/server/gdb_server.c
index d4cc2744c63f48839748a84be6b1b40c45cd1008..63c5f6bbd2e86914604dba4a78fcdb4f836a131b 100644 (file)
--- a/src/server/gdb_server.c
+++ b/src/server/gdb_server.c
@@ -2050,8 +2050,10 @@ static int get_reg_features_list(struct target *target, char **feature_list[], i
 static int gdb_generate_target_description(struct target *target, char **tdesc_out)
 {
        int retval = ERROR_OK;
-       struct reg **reg_list;
+       struct reg **reg_list = NULL;
        int reg_list_size;
+       char **features = NULL;
+       int feature_list_size = 0;
        char *tdesc = NULL;
        int pos = 0;
        int size = 0;
@@ -2061,21 +2063,22 @@ static int gdb_generate_target_description(struct target *target, char **tdesc_o
 
        if (retval != ERROR_OK) {
                LOG_ERROR("get register list failed");
-               return ERROR_FAIL;
+               retval = ERROR_FAIL;
+               goto error;
        }
 
        if (reg_list_size <= 0) {
-               free(reg_list);
-               return ERROR_FAIL;
+               LOG_ERROR("get register list failed");
+               retval = ERROR_FAIL;
+               goto error;
        }
 
-       char **features = NULL;
        /* Get a list of available target registers features */
-       retval = get_reg_features_list(target, &features, NULL, reg_list, reg_list_size);
+       retval = get_reg_features_list(target, &features, &feature_list_size, reg_list, reg_list_size);
        if (retval != ERROR_OK) {
                LOG_ERROR("Can't get the registers feature list");
-               free(reg_list);
-               return ERROR_FAIL;
+               retval = ERROR_FAIL;
+               goto error;
        }
 
        /* If we found some features associated with registers, create sections */
@@ -2155,8 +2158,13 @@ static int gdb_generate_target_description(struct target *target, char **tdesc_o
        xml_printf(&retval, &tdesc, &pos, &size,
                        "</target>\n");
 
-       free(reg_list);
+error:
+
+       /* note: features[] contains (feature_list_size + 1) elements */
+       for (int j = feature_list_size; j >= 0; j--)
+               free(features[j]);
        free(features);
+       free(reg_list);
 
        if (retval == ERROR_OK)
                *tdesc_out = tdesc;
@@ -2225,6 +2233,7 @@ static int gdb_target_description_supported(struct target *target, int *supporte
        int retval = ERROR_OK;
        struct reg **reg_list = NULL;
        int reg_list_size = 0;
+       char **features = NULL;
        int feature_list_size = 0;
        char **features = NULL;
 
@@ -2236,6 +2245,7 @@ static int gdb_target_description_supported(struct target *target, int *supporte
        }
 
        if (reg_list_size <= 0) {
+               LOG_ERROR("get register list failed");
                retval = ERROR_FAIL;
                goto error;
        }
@@ -2255,11 +2265,13 @@ static int gdb_target_description_supported(struct target *target, int *supporte
        }
 
 error:
-       if (reg_list != NULL)
-               free(reg_list);
 
-       if (features != NULL)
-               free(features);
+       /* note: features[] contains (feature_list_size + 1) elements */
+       for (int j = feature_list_size; j >= 0; j--)
+               free(features[j]);
+       free(features);
+
+       free(reg_list);
 
        return retval;
 }