module: group post-relocation functions into post_relocation()

This simply hoists more code out of load_module; we also put the
identification of the extable and dynamic debug table in with the
others in find_module_sections().

We move the taint check to the actual add/remove of the dynamic debug
info: this is certain (find_module_sections is too early).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Yehuda Sadeh <yehuda@hq.newdream.net>

1 files changed, 32 insertions, 24 deletions

diff --git a/kernel/module.c b/kernel/module.c
index cabafe228444..f3cba93ea1e3 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -117,6 +117,8 @@ struct load_info {
         char *secstrings, *strtab;
         unsigned long *strmap;
         unsigned long symoffs, stroffs;
+        struct _ddebug *debug;
+        unsigned int num_debug;
         struct {
                 unsigned int sym, str, mod, vers, info, pcpu;
         } index;
@@ -1993,7 +1995,7 @@ static void layout_symtab(struct module *mod, struct load_info *info)
         mod->core_size += bitmap_weight(info->strmap, strsect->sh_size);
 }
 
-static void add_kallsyms(struct module *mod, struct load_info *info)
+static void add_kallsyms(struct module *mod, const struct load_info *info)
 {
         unsigned int i, ndst;
         const Elf_Sym *src;
@@ -2040,6 +2042,8 @@ static void add_kallsyms(struct module *mod, struct load_info *info)
 
 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
 {
+        if (!debug)
+                return;
 #ifdef CONFIG_DYNAMIC_DEBUG
         if (ddebug_add_module(debug, num, debug->modname))
                 printk(KERN_ERR "dynamic debug error adding module: %s\n",
@@ -2267,8 +2271,7 @@ static int check_modinfo(struct module *mod, struct load_info *info)
         return 0;
 }
 
-static void find_module_sections(struct module *mod,
-                                 const struct load_info *info)
+static void find_module_sections(struct module *mod, struct load_info *info)
 {
         mod->kp = section_objs(info, "__param",
                                sizeof(*mod->kp), &mod->num_kp);
@@ -2323,9 +2326,15 @@ static void find_module_sections(struct module *mod,
                                              &mod->num_ftrace_callsites);
 #endif
 
+        mod->extable = section_objs(info, "__ex_table",
+                                    sizeof(*mod->extable), &mod->num_exentries);
+
         if (section_addr(info, "__obsparm"))
                 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
                        mod->name);
+
+        info->debug = section_objs(info, "__verbose",
+                                   sizeof(*info->debug), &info->num_debug);
 }
 
 static int move_module(struct module *mod, struct load_info *info)
@@ -2512,6 +2521,20 @@ static void module_deallocate(struct module *mod, struct load_info *info)
         module_free(mod, mod->module_core);
 }
 
+static int post_relocation(struct module *mod, const struct load_info *info)
+{
+        sort_extable(mod->extable, mod->extable + mod->num_exentries);
+
+        /* Copy relocated percpu area over. */
+        percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
+                       info->sechdrs[info->index.pcpu].sh_size);
+
+        add_kallsyms(mod, info);
+
+        /* Arch-specific module finalizing. */
+        return module_finalize(info->hdr, info->sechdrs, mod);
+}
+
 /* Allocate and load the module: note that size of section 0 is always
    zero, and we rely on this for optional sections. */
 static noinline struct module *load_module(void __user *umod,
@@ -2521,8 +2544,6 @@ static noinline struct module *load_module(void __user *umod,
         struct load_info info = { NULL, };
         struct module *mod;
         long err;
-        struct _ddebug *debug = NULL;
-        unsigned int num_debug = 0;
 
         DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
                umod, len, uargs);
@@ -2564,22 +2585,7 @@ static noinline struct module *load_module(void __user *umod,
         if (err < 0)
                 goto free_modinfo;
 
-        /* Set up and sort exception table */
-        mod->extable = section_objs(&info, "__ex_table",
-                                    sizeof(*mod->extable), &mod->num_exentries);
-        sort_extable(mod->extable, mod->extable + mod->num_exentries);
-
-        /* Finally, copy percpu area over. */
-        percpu_modcopy(mod, (void *)info.sechdrs[info.index.pcpu].sh_addr,
-                       info.sechdrs[info.index.pcpu].sh_size);
-
-        add_kallsyms(mod, &info);
-
-        if (!mod->taints)
-                debug = section_objs(&info, "__verbose",
-                                     sizeof(*debug), &num_debug);
-
-        err = module_finalize(info.hdr, info.sechdrs, mod);
+        err = post_relocation(mod, &info);
         if (err < 0)
                 goto free_modinfo;
 
@@ -2607,8 +2613,9 @@ static noinline struct module *load_module(void __user *umod,
                 goto unlock;
         }
 
-        if (debug)
-                dynamic_debug_setup(debug, num_debug);
+        /* This has to be done once we're sure module name is unique. */
+        if (!mod->taints)
+                dynamic_debug_setup(info.debug, info.num_debug);
 
         /* Find duplicate symbols */
         err = verify_export_symbols(mod);
@@ -2640,7 +2647,8 @@ static noinline struct module *load_module(void __user *umod,
         /* Unlink carefully: kallsyms could be walking list. */
         list_del_rcu(&mod->list);
  ddebug:
-        dynamic_debug_remove(debug);
+        if (!mod->taints)
+                dynamic_debug_remove(info.debug);
  unlock:
         mutex_unlock(&module_mutex);
         synchronize_sched();