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-rw-r--r--qemu/scripts/coverity-model.c343
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diff --git a/qemu/scripts/coverity-model.c b/qemu/scripts/coverity-model.c
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+/* Coverity Scan model
+ *
+ * Copyright (C) 2014 Red Hat, Inc.
+ *
+ * Authors:
+ * Markus Armbruster <armbru@redhat.com>
+ * Paolo Bonzini <pbonzini@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or, at your
+ * option, any later version. See the COPYING file in the top-level directory.
+ */
+
+
+/*
+ * This is the source code for our Coverity user model file. The
+ * purpose of user models is to increase scanning accuracy by explaining
+ * code Coverity can't see (out of tree libraries) or doesn't
+ * sufficiently understand. Better accuracy means both fewer false
+ * positives and more true defects. Memory leaks in particular.
+ *
+ * - A model file can't import any header files. Some built-in primitives are
+ * available but not wchar_t, NULL etc.
+ * - Modeling doesn't need full structs and typedefs. Rudimentary structs
+ * and similar types are sufficient.
+ * - An uninitialized local variable signifies that the variable could be
+ * any value.
+ *
+ * The model file must be uploaded by an admin in the analysis settings of
+ * http://scan.coverity.com/projects/378
+ */
+
+#define NULL ((void *)0)
+
+typedef unsigned char uint8_t;
+typedef char int8_t;
+typedef unsigned int uint32_t;
+typedef int int32_t;
+typedef long ssize_t;
+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;
+typedef uint64_t hwaddr;
+typedef uint32_t MemTxResult;
+typedef uint64_t MemTxAttrs;
+
+static void __bufwrite(uint8_t *buf, ssize_t len)
+{
+ int first, last;
+ __coverity_negative_sink__(len);
+ if (len == 0) return;
+ buf[0] = first;
+ buf[len-1] = last;
+ __coverity_writeall__(buf);
+}
+
+static void __bufread(uint8_t *buf, ssize_t len)
+{
+ __coverity_negative_sink__(len);
+ if (len == 0) return;
+ int first = buf[0];
+ int last = buf[len-1];
+}
+
+MemTxResult address_space_rw(AddressSpace *as, hwaddr addr, MemTxAttrs attrs,
+ uint8_t *buf, int len, bool is_write)
+{
+ MemTxResult result;
+
+ // TODO: investigate impact of treating reads as producing
+ // tainted data, with __coverity_tainted_data_argument__(buf).
+ if (is_write) __bufread(buf, len); else __bufwrite(buf, len);
+
+ return result;
+}
+
+/* Tainting */
+
+typedef struct {} name2keysym_t;
+static int get_keysym(const name2keysym_t *table,
+ const char *name)
+{
+ int result;
+ if (result > 0) {
+ __coverity_tainted_string_sanitize_content__(name);
+ return result;
+ } else {
+ return 0;
+ }
+}
+
+/*
+ * 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.
+ *
+ * Modeling this would result in Coverity flagging a lot of memory
+ * allocations as potentially returning NULL, and asking us to check
+ * whether the result of the allocation is NULL or not. However, the
+ * resulting pointer should never be dereferenced anyway, and in fact
+ * it is not in the vast majority of cases.
+ *
+ * If a dereference did happen, this would suppress a defect report
+ * for an actual null pointer dereference. But it's too unlikely to
+ * be worth wading through the false positives, and with some luck
+ * we'll get a buffer overflow reported anyway.
+ */
+
+/*
+ * 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__(sz);
+ __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__(sz);
+ __coverity_writeall0__(ptr);
+ __coverity_mark_as_afm_allocated__(ptr, "g_free");
+ return ptr;
+}
+
+void *g_realloc_n(void *ptr, size_t nmemb, size_t size)
+{
+ size_t sz;
+
+ __coverity_negative_sink__(nmemb);
+ __coverity_negative_sink__(size);
+ sz = nmemb * size;
+ __coverity_escape__(ptr);
+ ptr = __coverity_alloc__(sz);
+ /*
+ * 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_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)
+{
+ return g_malloc_n(1, size);
+}
+
+void *g_malloc0(size_t size)
+{
+ return g_malloc0_n(1, size);
+}
+
+void *g_realloc(void *ptr, size_t size)
+{
+ return g_realloc_n(ptr, 1, size);
+}
+
+void *g_try_malloc(size_t size)
+{
+ return g_try_malloc_n(1, size);
+}
+
+void *g_try_malloc0(size_t size)
+{
+ return g_try_malloc0_n(1, size);
+}
+
+void *g_try_realloc(void *ptr, size_t size)
+{
+ 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 */
+
+typedef struct _GIOChannel GIOChannel;
+GIOChannel *g_io_channel_unix_new(int fd)
+{
+ GIOChannel *c = g_malloc0(sizeof(GIOChannel));
+ __coverity_escape__(fd);
+ return c;
+}
+
+void g_assertion_message_expr(const char *domain,
+ const char *file,
+ int line,
+ const char *func,
+ const char *expr)
+{
+ __coverity_panic__();
+}