From 3fd6805f4dfb02bcfb5634972eabad0e790f119a Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Wed, 8 Feb 2006 21:16:45 +0100 Subject: [PATCH] Clean up module.c symbol searching logic Signed-off-by: Sam Ravnborg Signed-off-by: Greg Kroah-Hartman --- kernel/module.c | 73 ++++++++++++++++++++++++++++++++------------------------- 1 file changed, 41 insertions(+), 32 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 5aad477ddc79..2a892b20d68f 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -135,6 +135,18 @@ extern const unsigned long __start___kcrctab_gpl[]; #define symversion(base, idx) ((base) ? ((base) + (idx)) : NULL) #endif +/* lookup symbol in given range of kernel_symbols */ +static const struct kernel_symbol *lookup_symbol(const char *name, + const struct kernel_symbol *start, + const struct kernel_symbol *stop) +{ + const struct kernel_symbol *ks = start; + for (; ks < stop; ks++) + if (strcmp(ks->name, name) == 0) + return ks; + return NULL; +} + /* Find a symbol, return value, crc and module which owns it */ static unsigned long __find_symbol(const char *name, struct module **owner, @@ -142,39 +154,41 @@ static unsigned long __find_symbol(const char *name, int gplok) { struct module *mod; - unsigned int i; + const struct kernel_symbol *ks; /* Core kernel first. */ *owner = NULL; - for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++) { - if (strcmp(__start___ksymtab[i].name, name) == 0) { - *crc = symversion(__start___kcrctab, i); - return __start___ksymtab[i].value; - } + ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); + if (ks) { + *crc = symversion(__start___kcrctab, (ks - __start___ksymtab)); + return ks->value; } if (gplok) { - for (i = 0; __start___ksymtab_gpl+i<__stop___ksymtab_gpl; i++) - if (strcmp(__start___ksymtab_gpl[i].name, name) == 0) { - *crc = symversion(__start___kcrctab_gpl, i); - return __start___ksymtab_gpl[i].value; - } + ks = lookup_symbol(name, __start___ksymtab_gpl, + __stop___ksymtab_gpl); + if (ks) { + *crc = symversion(__start___kcrctab_gpl, + (ks - __start___ksymtab_gpl)); + return ks->value; + } } /* Now try modules. */ list_for_each_entry(mod, &modules, list) { *owner = mod; - for (i = 0; i < mod->num_syms; i++) - if (strcmp(mod->syms[i].name, name) == 0) { - *crc = symversion(mod->crcs, i); - return mod->syms[i].value; - } + ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); + if (ks) { + *crc = symversion(mod->crcs, (ks - mod->syms)); + return ks->value; + } if (gplok) { - for (i = 0; i < mod->num_gpl_syms; i++) { - if (strcmp(mod->gpl_syms[i].name, name) == 0) { - *crc = symversion(mod->gpl_crcs, i); - return mod->gpl_syms[i].value; - } + ks = lookup_symbol(name, mod->gpl_syms, + mod->gpl_syms + mod->num_gpl_syms); + if (ks) { + *crc = symversion(mod->gpl_crcs, + (ks - mod->gpl_syms)); + return ks->value; } } } @@ -1444,18 +1458,13 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, #ifdef CONFIG_KALLSYMS int is_exported(const char *name, const struct module *mod) { - unsigned int i; - - if (!mod) { - for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++) - if (strcmp(__start___ksymtab[i].name, name) == 0) - return 1; - return 0; - } - for (i = 0; i < mod->num_syms; i++) - if (strcmp(mod->syms[i].name, name) == 0) + if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab)) + return 1; + else + if (lookup_symbol(name, mod->syms, mod->syms + mod->num_syms)) return 1; - return 0; + else + return 0; } /* As per nm */ -- cgit v1.2.2 From 9f28bb7e1d0188a993403ab39b774785892805e1 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 20 Mar 2006 13:17:13 -0800 Subject: [PATCH] add EXPORT_SYMBOL_GPL_FUTURE() This patch adds the ability to mark symbols that will be changed in the future, so that kernel modules that don't include MODULE_LICENSE("GPL") and use the symbols, will be flagged and printed out to the system log. Signed-off-by: Greg Kroah-Hartman --- kernel/module.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 47 insertions(+), 2 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 2a892b20d68f..5ca99fbe9f44 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -126,8 +126,11 @@ extern const struct kernel_symbol __start___ksymtab[]; extern const struct kernel_symbol __stop___ksymtab[]; extern const struct kernel_symbol __start___ksymtab_gpl[]; extern const struct kernel_symbol __stop___ksymtab_gpl[]; +extern const struct kernel_symbol __start___ksymtab_gpl_future[]; +extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; extern const unsigned long __start___kcrctab[]; extern const unsigned long __start___kcrctab_gpl[]; +extern const unsigned long __start___kcrctab_gpl_future[]; #ifndef CONFIG_MODVERSIONS #define symversion(base, idx) NULL @@ -172,6 +175,22 @@ static unsigned long __find_symbol(const char *name, return ks->value; } } + ks = lookup_symbol(name, __start___ksymtab_gpl_future, + __stop___ksymtab_gpl_future); + if (ks) { + if (!gplok) { + printk(KERN_WARNING "Symbol %s is being used " + "by a non-GPL module, which will not " + "be allowed in the future\n", name); + printk(KERN_WARNING "Please see the file " + "Documentation/feature-removal-schedule.txt " + "in the kernel source tree for more " + "details.\n"); + } + *crc = symversion(__start___kcrctab_gpl_future, + (ks - __start___ksymtab_gpl_future)); + return ks->value; + } /* Now try modules. */ list_for_each_entry(mod, &modules, list) { @@ -191,6 +210,23 @@ static unsigned long __find_symbol(const char *name, return ks->value; } } + ks = lookup_symbol(name, mod->gpl_future_syms, + (mod->gpl_future_syms + + mod->num_gpl_future_syms)); + if (ks) { + if (!gplok) { + printk(KERN_WARNING "Symbol %s is being used " + "by a non-GPL module, which will not " + "be allowed in the future\n", name); + printk(KERN_WARNING "Please see the file " + "Documentation/feature-removal-schedule.txt " + "in the kernel source tree for more " + "details.\n"); + } + *crc = symversion(mod->gpl_future_crcs, + (ks - mod->gpl_future_syms)); + return ks->value; + } } DEBUGP("Failed to find symbol %s\n", name); return 0; @@ -1546,7 +1582,8 @@ static struct module *load_module(void __user *umod, char *secstrings, *args, *modmagic, *strtab = NULL; unsigned int i, symindex = 0, strindex = 0, setupindex, exindex, exportindex, modindex, obsparmindex, infoindex, gplindex, - crcindex, gplcrcindex, versindex, pcpuindex; + crcindex, gplcrcindex, versindex, pcpuindex, gplfutureindex, + gplfuturecrcindex; long arglen; struct module *mod; long err = 0; @@ -1627,8 +1664,10 @@ static struct module *load_module(void __user *umod, /* Optional sections */ exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab"); gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl"); + gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future"); crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab"); gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl"); + gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future"); setupindex = find_sec(hdr, sechdrs, secstrings, "__param"); exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table"); obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm"); @@ -1784,10 +1823,16 @@ static struct module *load_module(void __user *umod, mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr; if (gplcrcindex) mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr; + mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size / + sizeof(*mod->gpl_future_syms); + mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr; + if (gplfuturecrcindex) + mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr; #ifdef CONFIG_MODVERSIONS if ((mod->num_syms && !crcindex) || - (mod->num_gpl_syms && !gplcrcindex)) { + (mod->num_gpl_syms && !gplcrcindex) || + (mod->num_gpl_future_syms && !gplfuturecrcindex)) { printk(KERN_WARNING "%s: No versions for exported symbols." " Tainting kernel.\n", mod->name); add_taint(TAINT_FORCED_MODULE); -- cgit v1.2.2 From 03e88ae1b13dfdc8bbaa59b8198e1ca53aad12ac Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 16 Feb 2006 13:50:23 -0800 Subject: [PATCH] fix module sysfs files reference counting The module files, refcnt, version, and srcversion did not properly increment the owner's module reference count, allowing the modules to be removed while the files were open, causing oopses. This patch fixes this, and also fixes the problem that the version and srcversion files were not showing up, unless CONFIG_MODULE_UNLOAD was enabled, which is not correct. Cc: Nathan Lynch Signed-off-by: Greg Kroah-Hartman --- kernel/module.c | 77 +++++++++++++++++++++++---------------------------------- 1 file changed, 31 insertions(+), 46 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 5ca99fbe9f44..77764f22f021 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -429,7 +429,6 @@ static inline void percpu_modcopy(void *pcpudst, const void *src, } #endif /* CONFIG_SMP */ -#ifdef CONFIG_MODULE_UNLOAD #define MODINFO_ATTR(field) \ static void setup_modinfo_##field(struct module *mod, const char *s) \ { \ @@ -461,12 +460,7 @@ static struct module_attribute modinfo_##field = { \ MODINFO_ATTR(version); MODINFO_ATTR(srcversion); -static struct module_attribute *modinfo_attrs[] = { - &modinfo_version, - &modinfo_srcversion, - NULL, -}; - +#ifdef CONFIG_MODULE_UNLOAD /* Init the unload section of the module. */ static void module_unload_init(struct module *mod) { @@ -781,6 +775,15 @@ static inline void module_unload_init(struct module *mod) } #endif /* CONFIG_MODULE_UNLOAD */ +static struct module_attribute *modinfo_attrs[] = { + &modinfo_version, + &modinfo_srcversion, +#ifdef CONFIG_MODULE_UNLOAD + &refcnt, +#endif + NULL, +}; + #ifdef CONFIG_OBSOLETE_MODPARM /* Bounds checking done below */ static int obsparm_copy_string(const char *val, struct kernel_param *kp) @@ -1106,37 +1109,28 @@ static inline void remove_sect_attrs(struct module *mod) } #endif /* CONFIG_KALLSYMS */ - -#ifdef CONFIG_MODULE_UNLOAD -static inline int module_add_refcnt_attr(struct module *mod) -{ - return sysfs_create_file(&mod->mkobj.kobj, &refcnt.attr); -} -static void module_remove_refcnt_attr(struct module *mod) -{ - return sysfs_remove_file(&mod->mkobj.kobj, &refcnt.attr); -} -#else -static inline int module_add_refcnt_attr(struct module *mod) -{ - return 0; -} -static void module_remove_refcnt_attr(struct module *mod) -{ -} -#endif - -#ifdef CONFIG_MODULE_UNLOAD static int module_add_modinfo_attrs(struct module *mod) { struct module_attribute *attr; + struct module_attribute *temp_attr; int error = 0; int i; + mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * + (ARRAY_SIZE(modinfo_attrs) + 1)), + GFP_KERNEL); + if (!mod->modinfo_attrs) + return -ENOMEM; + + temp_attr = mod->modinfo_attrs; for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { if (!attr->test || - (attr->test && attr->test(mod))) - error = sysfs_create_file(&mod->mkobj.kobj,&attr->attr); + (attr->test && attr->test(mod))) { + memcpy(temp_attr, attr, sizeof(*temp_attr)); + temp_attr->attr.owner = mod; + error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr); + ++temp_attr; + } } return error; } @@ -1146,12 +1140,16 @@ static void module_remove_modinfo_attrs(struct module *mod) struct module_attribute *attr; int i; - for (i = 0; (attr = modinfo_attrs[i]); i++) { + for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { + /* pick a field to test for end of list */ + if (!attr->attr.name) + break; sysfs_remove_file(&mod->mkobj.kobj,&attr->attr); - attr->free(mod); + if (attr->free) + attr->free(mod); } + kfree(mod->modinfo_attrs); } -#endif static int mod_sysfs_setup(struct module *mod, struct kernel_param *kparam, @@ -1169,19 +1167,13 @@ static int mod_sysfs_setup(struct module *mod, if (err) goto out; - err = module_add_refcnt_attr(mod); - if (err) - goto out_unreg; - err = module_param_sysfs_setup(mod, kparam, num_params); if (err) goto out_unreg; -#ifdef CONFIG_MODULE_UNLOAD err = module_add_modinfo_attrs(mod); if (err) goto out_unreg; -#endif return 0; @@ -1193,10 +1185,7 @@ out: static void mod_kobject_remove(struct module *mod) { -#ifdef CONFIG_MODULE_UNLOAD module_remove_modinfo_attrs(mod); -#endif - module_remove_refcnt_attr(mod); module_param_sysfs_remove(mod); kobject_unregister(&mod->mkobj.kobj); @@ -1474,7 +1463,6 @@ static char *get_modinfo(Elf_Shdr *sechdrs, return NULL; } -#ifdef CONFIG_MODULE_UNLOAD static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, unsigned int infoindex) { @@ -1489,7 +1477,6 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, attr->attr.name)); } } -#endif #ifdef CONFIG_KALLSYMS int is_exported(const char *name, const struct module *mod) @@ -1803,10 +1790,8 @@ static struct module *load_module(void __user *umod, if (strcmp(mod->name, "driverloader") == 0) add_taint(TAINT_PROPRIETARY_MODULE); -#ifdef CONFIG_MODULE_UNLOAD /* Set up MODINFO_ATTR fields */ setup_modinfo(mod, sechdrs, infoindex); -#endif /* Fix up syms, so that st_value is a pointer to location. */ err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex, -- cgit v1.2.2 From 97d1f15b7ef52c1e9c28dc48b454024bb53a5fd2 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Thu, 23 Mar 2006 03:00:24 -0800 Subject: [PATCH] sem2mutex: kernel/ Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 77764f22f021..de6312da6bb5 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -63,15 +64,15 @@ static DEFINE_SPINLOCK(modlist_lock); static DECLARE_MUTEX(module_mutex); static LIST_HEAD(modules); -static DECLARE_MUTEX(notify_mutex); +static DEFINE_MUTEX(notify_mutex); static struct notifier_block * module_notify_list; int register_module_notifier(struct notifier_block * nb) { int err; - down(¬ify_mutex); + mutex_lock(¬ify_mutex); err = notifier_chain_register(&module_notify_list, nb); - up(¬ify_mutex); + mutex_unlock(¬ify_mutex); return err; } EXPORT_SYMBOL(register_module_notifier); @@ -79,9 +80,9 @@ EXPORT_SYMBOL(register_module_notifier); int unregister_module_notifier(struct notifier_block * nb) { int err; - down(¬ify_mutex); + mutex_lock(¬ify_mutex); err = notifier_chain_unregister(&module_notify_list, nb); - up(¬ify_mutex); + mutex_unlock(¬ify_mutex); return err; } EXPORT_SYMBOL(unregister_module_notifier); @@ -1989,9 +1990,9 @@ sys_init_module(void __user *umod, /* Drop lock so they can recurse */ up(&module_mutex); - down(¬ify_mutex); + mutex_lock(¬ify_mutex); notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod); - up(¬ify_mutex); + mutex_unlock(¬ify_mutex); /* Start the module */ if (mod->init != NULL) -- cgit v1.2.2 From 6389a385114ae358693f213266de6468ea116c77 Mon Sep 17 00:00:00 2001 From: Ashutosh Naik Date: Thu, 23 Mar 2006 03:00:46 -0800 Subject: [PATCH] kernel/module.c Semaphore to Mutex Conversion for module_mutex This patch converts the module_mutex semaphore to a mutex. Signed-off-by: Ashutosh Naik Cc: Arjan van de Ven Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index de6312da6bb5..fb404299082e 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -61,7 +61,7 @@ static DEFINE_SPINLOCK(modlist_lock); /* List of modules, protected by module_mutex AND modlist_lock */ -static DECLARE_MUTEX(module_mutex); +static DEFINE_MUTEX(module_mutex); static LIST_HEAD(modules); static DEFINE_MUTEX(notify_mutex); @@ -602,7 +602,7 @@ static void free_module(struct module *mod); static void wait_for_zero_refcount(struct module *mod) { /* Since we might sleep for some time, drop the semaphore first */ - up(&module_mutex); + mutex_unlock(&module_mutex); for (;;) { DEBUGP("Looking at refcount...\n"); set_current_state(TASK_UNINTERRUPTIBLE); @@ -611,7 +611,7 @@ static void wait_for_zero_refcount(struct module *mod) schedule(); } current->state = TASK_RUNNING; - down(&module_mutex); + mutex_lock(&module_mutex); } asmlinkage long @@ -628,7 +628,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) return -EFAULT; name[MODULE_NAME_LEN-1] = '\0'; - if (down_interruptible(&module_mutex) != 0) + if (mutex_lock_interruptible(&module_mutex) != 0) return -EINTR; mod = find_module(name); @@ -677,14 +677,14 @@ sys_delete_module(const char __user *name_user, unsigned int flags) /* Final destruction now noone is using it. */ if (mod->exit != NULL) { - up(&module_mutex); + mutex_unlock(&module_mutex); mod->exit(); - down(&module_mutex); + mutex_lock(&module_mutex); } free_module(mod); out: - up(&module_mutex); + mutex_unlock(&module_mutex); return ret; } @@ -1973,13 +1973,13 @@ sys_init_module(void __user *umod, return -EPERM; /* Only one module load at a time, please */ - if (down_interruptible(&module_mutex) != 0) + if (mutex_lock_interruptible(&module_mutex) != 0) return -EINTR; /* Do all the hard work */ mod = load_module(umod, len, uargs); if (IS_ERR(mod)) { - up(&module_mutex); + mutex_unlock(&module_mutex); return PTR_ERR(mod); } @@ -1988,7 +1988,7 @@ sys_init_module(void __user *umod, stop_machine_run(__link_module, mod, NR_CPUS); /* Drop lock so they can recurse */ - up(&module_mutex); + mutex_unlock(&module_mutex); mutex_lock(¬ify_mutex); notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod); @@ -2007,15 +2007,15 @@ sys_init_module(void __user *umod, mod->name); else { module_put(mod); - down(&module_mutex); + mutex_lock(&module_mutex); free_module(mod); - up(&module_mutex); + mutex_unlock(&module_mutex); } return ret; } /* Now it's a first class citizen! */ - down(&module_mutex); + mutex_lock(&module_mutex); mod->state = MODULE_STATE_LIVE; /* Drop initial reference. */ module_put(mod); @@ -2023,7 +2023,7 @@ sys_init_module(void __user *umod, mod->module_init = NULL; mod->init_size = 0; mod->init_text_size = 0; - up(&module_mutex); + mutex_unlock(&module_mutex); return 0; } @@ -2113,7 +2113,7 @@ struct module *module_get_kallsym(unsigned int symnum, { struct module *mod; - down(&module_mutex); + mutex_lock(&module_mutex); list_for_each_entry(mod, &modules, list) { if (symnum < mod->num_symtab) { *value = mod->symtab[symnum].st_value; @@ -2121,12 +2121,12 @@ struct module *module_get_kallsym(unsigned int symnum, strncpy(namebuf, mod->strtab + mod->symtab[symnum].st_name, 127); - up(&module_mutex); + mutex_unlock(&module_mutex); return mod; } symnum -= mod->num_symtab; } - up(&module_mutex); + mutex_unlock(&module_mutex); return NULL; } @@ -2169,7 +2169,7 @@ static void *m_start(struct seq_file *m, loff_t *pos) struct list_head *i; loff_t n = 0; - down(&module_mutex); + mutex_lock(&module_mutex); list_for_each(i, &modules) { if (n++ == *pos) break; @@ -2190,7 +2190,7 @@ static void *m_next(struct seq_file *m, void *p, loff_t *pos) static void m_stop(struct seq_file *m, void *p) { - up(&module_mutex); + mutex_unlock(&module_mutex); } static int m_show(struct seq_file *m, void *p) -- cgit v1.2.2