diff mbox series

[RESEND,v5,14/26] gdbstub: Dynamically allocate target.xml buffer

Message ID 20230818033648.8326-15-akihiko.odaki@daynix.com
State New
Headers show
Series plugins: Allow to read registers | expand

Commit Message

Akihiko Odaki Aug. 18, 2023, 3:36 a.m. UTC 
There is no guarantee that target.xml fits in 1024 bytes, and the fixed
buffer length requires tedious buffer overflow check. Dynamically
allocate the target.xml buffer to resolve these problems.

Suggested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 gdbstub/internals.h |  2 +-
 gdbstub/gdbstub.c   | 44 ++++++++++++++++++++++++--------------------
 gdbstub/softmmu.c   |  2 +-
 3 files changed, 26 insertions(+), 22 deletions(-)
diff mbox series

Patch

diff --git a/gdbstub/internals.h b/gdbstub/internals.h
index f2b46cce41..4876ebd74f 100644
--- a/gdbstub/internals.h
+++ b/gdbstub/internals.h
@@ -33,7 +33,7 @@  typedef struct GDBProcess {
     uint32_t pid;
     bool attached;
 
-    char target_xml[1024];
+    char *target_xml;
 } GDBProcess;
 
 enum RSState {
diff --git a/gdbstub/gdbstub.c b/gdbstub/gdbstub.c
index 5656a44970..031ad89c7d 100644
--- a/gdbstub/gdbstub.c
+++ b/gdbstub/gdbstub.c
@@ -366,33 +366,37 @@  static const char *get_feature_xml(const char *p, const char **newp,
 
     name = NULL;
     if (strncmp(p, "target.xml", len) == 0) {
-        char *buf = process->target_xml;
-        const size_t buf_sz = sizeof(process->target_xml);
-
         /* Generate the XML description for this CPU.  */
-        if (!buf[0]) {
+        if (!process->target_xml) {
+            g_autoptr(GPtrArray) a = g_ptr_array_new_with_free_func(g_free);
             GDBRegisterState *r;
 
-            pstrcat(buf, buf_sz,
-                    "<?xml version=\"1.0\"?>"
-                    "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
-                    "<target>");
+            g_ptr_array_add(
+                a,
+                g_strdup("<?xml version=\"1.0\"?>"
+                         "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
+                         "<target>"));
             if (cc->gdb_arch_name) {
-                pstrcat(buf, buf_sz, "<architecture>");
-                pstrcat(buf, buf_sz, cc->gdb_arch_name(cpu));
-                pstrcat(buf, buf_sz, "</architecture>");
+                g_ptr_array_add(
+                    a,
+                    g_markup_printf_escaped("<architecture>%s</architecture>",
+                                            cc->gdb_arch_name(cpu)));
             }
-            pstrcat(buf, buf_sz, "<xi:include href=\"");
-            pstrcat(buf, buf_sz, cc->gdb_core_feature->xmlname);
-            pstrcat(buf, buf_sz, "\"/>");
+            g_ptr_array_add(
+                a,
+                g_markup_printf_escaped("<xi:include href=\"%s\"/>",
+                                        cc->gdb_core_feature->xmlname));
             for (r = cpu->gdb_regs; r; r = r->next) {
-                pstrcat(buf, buf_sz, "<xi:include href=\"");
-                pstrcat(buf, buf_sz, r->feature->xmlname);
-                pstrcat(buf, buf_sz, "\"/>");
+                g_ptr_array_add(
+                    a,
+                    g_markup_printf_escaped("<xi:include href=\"%s\"/>",
+                                            r->feature->xmlname));
             }
-            pstrcat(buf, buf_sz, "</target>");
+            g_ptr_array_add(a, g_strdup("</target>"));
+            g_ptr_array_add(a, NULL);
+            process->target_xml = g_strjoinv(NULL, (void *)a->pdata);
         }
-        return buf;
+        return process->target_xml;
     }
     if (cc->gdb_get_dynamic_xml) {
         char *xmlname = g_strndup(p, len);
@@ -2270,6 +2274,6 @@  void gdb_create_default_process(GDBState *s)
     process = &s->processes[s->process_num - 1];
     process->pid = pid;
     process->attached = false;
-    process->target_xml[0] = '\0';
+    process->target_xml = NULL;
 }
 
diff --git a/gdbstub/softmmu.c b/gdbstub/softmmu.c
index f509b7285d..5282324764 100644
--- a/gdbstub/softmmu.c
+++ b/gdbstub/softmmu.c
@@ -293,7 +293,7 @@  static int find_cpu_clusters(Object *child, void *opaque)
         assert(cluster->cluster_id != UINT32_MAX);
         process->pid = cluster->cluster_id + 1;
         process->attached = false;
-        process->target_xml[0] = '\0';
+        process->target_xml = NULL;
 
         return 0;
     }