---

yaml --- r: 147942 b: refs/heads/master c: ad6561d h: refs/heads/master v: v3
git-mirror · Jun 12, 2009 · 40ead7c · 40ead7c
1 parent bb8dbe7
commit 40ead7c
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Showing 8 changed files with 102 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c398df30d5caad626ac72bfab0361a7b0f67a661
+refs/heads/master: ad6561dffa17f17bb68d7207d422c26c381c4313
diff --git a/trunk/arch/alpha/mm/extable.c b/trunk/arch/alpha/mm/extable.c
@@ -48,6 +48,27 @@ void sort_extable(struct exception_table_entry *start,
 	     cmp_ex, swap_ex);
 }
 
+#ifdef CONFIG_MODULES
+/*
+ * Any entry referring to the module init will be at the beginning or
+ * the end.
+ */
+void trim_init_extable(struct module *m)
+{
+	/*trim the beginning*/
+	while (m->num_exentries &&
+	       within_module_init(ex_to_addr(&m->extable[0]), m)) {
+		m->extable++;
+		m->num_exentries--;
+	}
+	/*trim the end*/
+	while (m->num_exentries &&
+	       within_module_init(ex_to_addr(&m->extable[m->num_exentries-1]),
+				  m))
+		m->num_exentries--;
+}
+#endif /* CONFIG_MODULES */
+
 const struct exception_table_entry *
 search_extable(const struct exception_table_entry *first,
 	       const struct exception_table_entry *last,

diff --git a/trunk/arch/ia64/mm/extable.c b/trunk/arch/ia64/mm/extable.c
@@ -53,6 +53,32 @@ void sort_extable (struct exception_table_entry *start,
 	     cmp_ex, swap_ex);
 }
 
+static inline unsigned long ex_to_addr(const struct exception_table_entry *x)
+{
+	return (unsigned long)&x->insn + x->insn;
+}
+
+#ifdef CONFIG_MODULES
+/*
+ * Any entry referring to the module init will be at the beginning or
+ * the end.
+ */
+void trim_init_extable(struct module *m)
+{
+	/*trim the beginning*/
+	while (m->num_exentries &&
+	       within_module_init(ex_to_addr(&m->extable[0]), m)) {
+		m->extable++;
+		m->num_exentries--;
+	}
+	/*trim the end*/
+	while (m->num_exentries &&
+	       within_module_init(ex_to_addr(&m->extable[m->num_exentries-1]),
+				  m))
+		m->num_exentries--;
+}
+#endif /* CONFIG_MODULES */
+
 const struct exception_table_entry *
 search_extable (const struct exception_table_entry *first,
 		const struct exception_table_entry *last,

diff --git a/trunk/arch/sparc/include/asm/uaccess_32.h b/trunk/arch/sparc/include/asm/uaccess_32.h
@@ -17,6 +17,9 @@
 
 #ifndef __ASSEMBLY__
 
+#define ARCH_HAS_SORT_EXTABLE
+#define ARCH_HAS_SEARCH_EXTABLE
+
 /* Sparc is not segmented, however we need to be able to fool access_ok()
  * when doing system calls from kernel mode legitimately.
  *

diff --git a/trunk/arch/sparc/mm/extable.c b/trunk/arch/sparc/mm/extable.c
@@ -28,6 +28,10 @@ search_extable(const struct exception_table_entry *start,
 	 *	word 3: last insn address + 4 bytes
 	 *	word 4: fixup code address
 	 *
+	 * Deleted entries are encoded as:
+	 *	word 1: unused
+	 *	word 2: -1
+	 *
 	 * See asm/uaccess.h for more details.
 	 */
 
@@ -39,6 +43,10 @@ search_extable(const struct exception_table_entry *start,
 			continue;
 		}
 
+		/* A deleted entry; see trim_init_extable */
+		if (walk->fixup == -1)
+			continue;
+
 		if (walk->insn == value)
 			return walk;
 	}
@@ -57,6 +65,27 @@ search_extable(const struct exception_table_entry *start,
         return NULL;
 }
 
+#ifdef CONFIG_MODULES
+/* We could memmove them around; easier to mark the trimmed ones. */
+void trim_init_extable(struct module *m)
+{
+	unsigned int i;
+	bool range;
+
+	for (i = 0; i < m->num_exentries; i += range ? 2 : 1) {
+		range = m->extable[i].fixup == 0;
+
+		if (within_module_init(m->extable[i].insn, m)) {
+			m->extable[i].fixup = -1;
+			if (range)
+				m->extable[i+1].fixup = -1;
+		}
+		if (range)
+			i++;
+	}
+}
+#endif /* CONFIG_MODULES */
+
 /* Special extable search, which handles ranges.  Returns fixup */
 unsigned long search_extables_range(unsigned long addr, unsigned long *g2)
 {

diff --git a/trunk/include/linux/module.h b/trunk/include/linux/module.h
@@ -77,6 +77,7 @@ search_extable(const struct exception_table_entry *first,
 void sort_extable(struct exception_table_entry *start,
 		  struct exception_table_entry *finish);
 void sort_main_extable(void);
+void trim_init_extable(struct module *m);
 
 #ifdef MODULE
 #define MODULE_GENERIC_TABLE(gtype,name)			\

diff --git a/trunk/kernel/module.c b/trunk/kernel/module.c
@@ -2455,6 +2455,7 @@ SYSCALL_DEFINE3(init_module, void __user *, umod,
 	mutex_lock(&module_mutex);
 	/* Drop initial reference. */
 	module_put(mod);
+	trim_init_extable(mod);
 	module_free(mod, mod->module_init);
 	mod->module_init = NULL;
 	mod->init_size = 0;

diff --git a/trunk/lib/extable.c b/trunk/lib/extable.c
@@ -39,7 +39,26 @@ void sort_extable(struct exception_table_entry *start,
 	sort(start, finish - start, sizeof(struct exception_table_entry),
 	     cmp_ex, NULL);
 }
-#endif
+
+#ifdef CONFIG_MODULES
+/*
+ * If the exception table is sorted, any referring to the module init
+ * will be at the beginning or the end.
+ */
+void trim_init_extable(struct module *m)
+{
+	/*trim the beginning*/
+	while (m->num_exentries && within_module_init(m->extable[0].insn, m)) {
+		m->extable++;
+		m->num_exentries--;
+	}
+	/*trim the end*/
+	while (m->num_exentries &&
+		within_module_init(m->extable[m->num_exentries-1].insn, m))
+		m->num_exentries--;
+}
+#endif /* CONFIG_MODULES */
+#endif /* !ARCH_HAS_SORT_EXTABLE */
 
 #ifndef ARCH_HAS_SEARCH_EXTABLE
 /*