Merge remote-tracking branch 'remotes/armbru/tags/pull-cov-model-2015-02-05' into staging

coverity: Improve and extend model

# gpg: Signature made Thu 05 Feb 2015 16:20:49 GMT using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-cov-model-2015-02-05:
  MAINTAINERS: Add myself as Coverity model maintainer
  coverity: Model g_free() isn't necessarily free()
  coverity: Model GLib string allocation partially
  coverity: Improve model for GLib memory allocation

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 198 insertions, 35 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index fd335a47bf..b68cb7e133 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -783,6 +783,11 @@ M: Samuel Thibault <samuel.thibault@ens-lyon.org>
 S: Maintained
 F: backends/baum.c
 
+Coverity model
+M: Markus Armbruster <armbru@redhat.com>
+S: Supported
+F: scripts/coverity-model.c
+
 CPU
 M: Andreas Färber <afaerber@suse.de>
 S: Supported
diff --git a/scripts/coverity-model.c b/scripts/coverity-model.c
index 4c99a85cfc..58356afa66 100644
--- a/scripts/coverity-model.c
+++ b/scripts/coverity-model.c
@@ -40,6 +40,8 @@ typedef unsigned long long uint64_t;
 typedef long long int64_t;
 typedef _Bool bool;
 
+typedef struct va_list_str *va_list;
+
 /* exec.c */
 
 typedef struct AddressSpace AddressSpace;
@@ -90,7 +92,8 @@ static int get_keysym(const name2keysym_t *table,
     }
 }
 
-/* glib memory allocation functions.
+/*
+ * GLib memory allocation functions.
  *
  * Note that we ignore the fact that g_malloc of 0 bytes returns NULL,
  * and g_realloc of 0 bytes frees the pointer.
@@ -107,60 +110,215 @@ static int get_keysym(const name2keysym_t *table,
  * we'll get a buffer overflow reported anyway.
  */
 
-void *malloc(size_t);
-void *calloc(size_t, size_t);
-void *realloc(void *, size_t);
-void free(void *);
+/*
+ * Allocation primitives, cannot return NULL
+ * See also Coverity's library/generic/libc/all/all.c
+ */
+
+void *g_malloc_n(size_t nmemb, size_t size)
+{
+    size_t sz;
+    void *ptr;
+
+    __coverity_negative_sink__(nmemb);
+    __coverity_negative_sink__(size);
+    sz = nmemb * size;
+    ptr = __coverity_alloc__(size);
+    __coverity_mark_as_uninitialized_buffer__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, "g_free");
+    return ptr;
+}
+
+void *g_malloc0_n(size_t nmemb, size_t size)
+{
+    size_t sz;
+    void *ptr;
+
+    __coverity_negative_sink__(nmemb);
+    __coverity_negative_sink__(size);
+    sz = nmemb * size;
+    ptr = __coverity_alloc__(size);
+    __coverity_writeall0__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, "g_free");
+    return ptr;
+}
 
-void *
-g_malloc(size_t n_bytes)
+void *g_realloc_n(void *ptr, size_t nmemb, size_t size)
 {
-    void *mem;
-    __coverity_negative_sink__(n_bytes);
-    mem = malloc(n_bytes == 0 ? 1 : n_bytes);
-    if (!mem) __coverity_panic__();
-    return mem;
+    size_t sz;
+
+    __coverity_negative_sink__(nmemb);
+    __coverity_negative_sink__(size);
+    sz = nmemb * size;
+    __coverity_escape__(ptr);
+    ptr = __coverity_alloc__(size);
+    /*
+     * Memory beyond the old size isn't actually initialized.  Can't
+     * model that.  See Coverity's realloc() model
+     */
+    __coverity_writeall__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, "g_free");
+    return ptr;
 }
 
-void *
-g_malloc0(size_t n_bytes)
+void g_free(void *ptr)
+{
+    __coverity_free__(ptr);
+    __coverity_mark_as_afm_freed__(ptr, "g_free");
+}
+
+/*
+ * Derive the g_try_FOO_n() from the g_FOO_n() by adding indeterminate
+ * out of memory conditions
+ */
+
+void *g_try_malloc_n(size_t nmemb, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_malloc_n(nmemb, size);
+}
+
+void *g_try_malloc0_n(size_t nmemb, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_malloc0_n(nmemb, size);
+}
+
+void *g_try_realloc_n(void *ptr, size_t nmemb, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_realloc_n(ptr, nmemb, size);
+}
+
+/* Trivially derive the g_FOO() from the g_FOO_n() */
+
+void *g_malloc(size_t size)
 {
-    void *mem;
-    __coverity_negative_sink__(n_bytes);
-    mem = calloc(1, n_bytes == 0 ? 1 : n_bytes);
-    if (!mem) __coverity_panic__();
-    return mem;
+    return g_malloc_n(1, size);
 }
 
-void g_free(void *mem)
+void *g_malloc0(size_t size)
 {
-    free(mem);
+    return g_malloc0_n(1, size);
 }
 
-void *g_realloc(void * mem, size_t n_bytes)
+void *g_realloc(void *ptr, size_t size)
 {
-    __coverity_negative_sink__(n_bytes);
-    mem = realloc(mem, n_bytes == 0 ? 1 : n_bytes);
-    if (!mem) __coverity_panic__();
-    return mem;
+    return g_realloc_n(ptr, 1, size);
 }
 
-void *g_try_malloc(size_t n_bytes)
+void *g_try_malloc(size_t size)
 {
-    __coverity_negative_sink__(n_bytes);
-    return malloc(n_bytes == 0 ? 1 : n_bytes);
+    return g_try_malloc_n(1, size);
 }
 
-void *g_try_malloc0(size_t n_bytes)
+void *g_try_malloc0(size_t size)
 {
-    __coverity_negative_sink__(n_bytes);
-    return calloc(1, n_bytes == 0 ? 1 : n_bytes);
+    return g_try_malloc0_n(1, size);
 }
 
-void *g_try_realloc(void *mem, size_t n_bytes)
+void *g_try_realloc(void *ptr, size_t size)
 {
-    __coverity_negative_sink__(n_bytes);
-    return realloc(mem, n_bytes == 0 ? 1 : n_bytes);
+    return g_try_realloc_n(ptr, 1, size);
+}
+
+/*
+ * GLib string allocation functions
+ */
+
+char *g_strdup(const char *s)
+{
+    char *dup;
+    size_t i;
+
+    if (!s) {
+        return NULL;
+    }
+
+    __coverity_string_null_sink__(s);
+    __coverity_string_size_sink__(s);
+    dup = __coverity_alloc_nosize__();
+    __coverity_mark_as_afm_allocated__(dup, "g_free");
+    for (i = 0; (dup[i] = s[i]); i++) ;
+    return dup;
+}
+
+char *g_strndup(const char *s, size_t n)
+{
+    char *dup;
+    size_t i;
+
+    __coverity_negative_sink__(n);
+
+    if (!s) {
+        return NULL;
+    }
+
+    dup = g_malloc(n + 1);
+    for (i = 0; i < n && (dup[i] = s[i]); i++) ;
+    dup[i] = 0;
+    return dup;
+}
+
+char *g_strdup_printf(const char *format, ...)
+{
+    char ch, *s;
+    size_t len;
+
+    __coverity_string_null_sink__(format);
+    __coverity_string_size_sink__(format);
+
+    ch = *format;
+
+    s = __coverity_alloc_nosize__();
+    __coverity_writeall__(s);
+    __coverity_mark_as_afm_allocated__(s, "g_free");
+    return s;
+}
+
+char *g_strdup_vprintf(const char *format, va_list ap)
+{
+    char ch, *s;
+    size_t len;
+
+    __coverity_string_null_sink__(format);
+    __coverity_string_size_sink__(format);
+
+    ch = *format;
+    ch = *(char *)ap;
+
+    s = __coverity_alloc_nosize__();
+    __coverity_writeall__(s);
+    __coverity_mark_as_afm_allocated__(s, "g_free");
+
+    return len;
+}
+
+char *g_strconcat(const char *s, ...)
+{
+    char *s;
+
+    /*
+     * Can't model: last argument must be null, the others
+     * null-terminated strings
+     */
+
+    s = __coverity_alloc_nosize__();
+    __coverity_writeall__(s);
+    __coverity_mark_as_afm_allocated__(s, "g_free");
+    return s;
 }
 
 /* Other glib functions */