From 1cc5f7142eca352109895fe20b1fc6405dd17727 Mon Sep 17 00:00:00 2001 From: Ed Swierk Date: Mon, 25 Sep 2006 16:25:36 -0700 Subject: [PATCH] load_module: no BUG if module_subsys uninitialized Invoking load_module() before param_sysfs_init() is called crashes in mod_sysfs_setup(), since the kset in module_subsys is not initialized yet. In my case, net-pf-1 is getting modprobed as a result of hotplug trying to create a UNIX socket. Calls to hotplug begin after the topology_init initcall. Another patch for the same symptom (module_subsys-initialize-earlier.patch) moves param_sysfs_init() to the subsys initcalls, but this is still not early enough in the boot process in some cases. In particular, topology_init() causes /sbin/hotplug to run, which requests net-pf-1 (the UNIX socket protocol) which can be compiled as a module. Moving param_sysfs_init() to the postcore initcalls fixes this particular race, but there might well be other cases where a usermodehelper causes a module to load earlier still. The patch makes load_module() return an error rather than crashing the kernel if invoked before module_subsys is initialized. Cc: Mark Huang Cc: Greg KH Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 2a19cd47c046..b7fe6e840963 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1054,6 +1054,12 @@ static int mod_sysfs_setup(struct module *mod, { int err; + if (!module_subsys.kset.subsys) { + printk(KERN_ERR "%s: module_subsys not initialized\n", + mod->name); + err = -EINVAL; + goto out; + } memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name); if (err) -- cgit v1.2.3 From 04b1db9fd7eea63c9663072feece616ea41b0a79 Mon Sep 17 00:00:00 2001 From: "Ian S. Nelson" Date: Fri, 29 Sep 2006 02:01:31 -0700 Subject: [PATCH] /sys/modules: allow full length section names I've been using systemtap for some debugging and I noticed that it can't probe a lot of modules. Turns out it's kind of silly, the sections section of /sys/module is limited to 32byte filenames and many of the actual sections are a a bit longer than that. [akpm@osdl.org: rewrite to use dymanic allocation] Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index b7fe6e840963..05625d5dc758 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -933,6 +933,15 @@ static ssize_t module_sect_show(struct module_attribute *mattr, return sprintf(buf, "0x%lx\n", sattr->address); } +static void free_sect_attrs(struct module_sect_attrs *sect_attrs) +{ + int section; + + for (section = 0; section < sect_attrs->nsections; section++) + kfree(sect_attrs->attrs[section].name); + kfree(sect_attrs); +} + static void add_sect_attrs(struct module *mod, unsigned int nsect, char *secstrings, Elf_Shdr *sechdrs) { @@ -949,21 +958,26 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect, + nloaded * sizeof(sect_attrs->attrs[0]), sizeof(sect_attrs->grp.attrs[0])); size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); - if (! (sect_attrs = kmalloc(size[0] + size[1], GFP_KERNEL))) + sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); + if (sect_attrs == NULL) return; /* Setup section attributes. */ sect_attrs->grp.name = "sections"; sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; + sect_attrs->nsections = 0; sattr = §_attrs->attrs[0]; gattr = §_attrs->grp.attrs[0]; for (i = 0; i < nsect; i++) { if (! (sechdrs[i].sh_flags & SHF_ALLOC)) continue; sattr->address = sechdrs[i].sh_addr; - strlcpy(sattr->name, secstrings + sechdrs[i].sh_name, - MODULE_SECT_NAME_LEN); + sattr->name = kstrdup(secstrings + sechdrs[i].sh_name, + GFP_KERNEL); + if (sattr->name == NULL) + goto out; + sect_attrs->nsections++; sattr->mattr.show = module_sect_show; sattr->mattr.store = NULL; sattr->mattr.attr.name = sattr->name; @@ -979,7 +993,7 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect, mod->sect_attrs = sect_attrs; return; out: - kfree(sect_attrs); + free_sect_attrs(sect_attrs); } static void remove_sect_attrs(struct module *mod) @@ -989,13 +1003,13 @@ static void remove_sect_attrs(struct module *mod) &mod->sect_attrs->grp); /* We are positive that no one is using any sect attrs * at this point. Deallocate immediately. */ - kfree(mod->sect_attrs); + free_sect_attrs(mod->sect_attrs); mod->sect_attrs = NULL; } } - #else + static inline void add_sect_attrs(struct module *mod, unsigned int nsect, char *sectstrings, Elf_Shdr *sechdrs) { -- cgit v1.2.3