From 0ffc40f6c8ab684e694774ebc835b198398129a8 Mon Sep 17 00:00:00 2001 From: Aaron Tomlin Date: Tue, 22 Mar 2022 14:03:41 +0000 Subject: module: Move procfs support into a separate file No functional change. This patch migrates code that allows one to generate a list of loaded/or linked modules via /proc when procfs support is enabled into kernel/module/procfs.c. Reviewed-by: Christophe Leroy Signed-off-by: Aaron Tomlin Signed-off-by: Luis Chamberlain --- kernel/module/procfs.c | 142 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 142 insertions(+) create mode 100644 kernel/module/procfs.c (limited to 'kernel/module/procfs.c') diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c new file mode 100644 index 000000000000..2717e130788e --- /dev/null +++ b/kernel/module/procfs.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module proc support + * + * Copyright (C) 2008 Alexey Dobriyan + */ + +#include +#include +#include +#include +#include +#include "internal.h" + +#ifdef CONFIG_MODULE_UNLOAD +static inline void print_unload_info(struct seq_file *m, struct module *mod) +{ + struct module_use *use; + int printed_something = 0; + + seq_printf(m, " %i ", module_refcount(mod)); + + /* + * Always include a trailing , so userspace can differentiate + * between this and the old multi-field proc format. + */ + list_for_each_entry(use, &mod->source_list, source_list) { + printed_something = 1; + seq_printf(m, "%s,", use->source->name); + } + + if (mod->init && !mod->exit) { + printed_something = 1; + seq_puts(m, "[permanent],"); + } + + if (!printed_something) + seq_puts(m, "-"); +} +#else /* !CONFIG_MODULE_UNLOAD */ +static inline void print_unload_info(struct seq_file *m, struct module *mod) +{ + /* We don't know the usage count, or what modules are using. */ + seq_puts(m, " - -"); +} +#endif /* CONFIG_MODULE_UNLOAD */ + +/* Called by the /proc file system to return a list of modules. */ +static void *m_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&module_mutex); + return seq_list_start(&modules, *pos); +} + +static void *m_next(struct seq_file *m, void *p, loff_t *pos) +{ + return seq_list_next(p, &modules, pos); +} + +static void m_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&module_mutex); +} + +static int m_show(struct seq_file *m, void *p) +{ + struct module *mod = list_entry(p, struct module, list); + char buf[MODULE_FLAGS_BUF_SIZE]; + void *value; + + /* We always ignore unformed modules. */ + if (mod->state == MODULE_STATE_UNFORMED) + return 0; + + seq_printf(m, "%s %u", + mod->name, mod->init_layout.size + mod->core_layout.size); + print_unload_info(m, mod); + + /* Informative for users. */ + seq_printf(m, " %s", + mod->state == MODULE_STATE_GOING ? "Unloading" : + mod->state == MODULE_STATE_COMING ? "Loading" : + "Live"); + /* Used by oprofile and other similar tools. */ + value = m->private ? NULL : mod->core_layout.base; + seq_printf(m, " 0x%px", value); + + /* Taints info */ + if (mod->taints) + seq_printf(m, " %s", module_flags(mod, buf)); + + seq_puts(m, "\n"); + return 0; +} + +/* + * Format: modulename size refcount deps address + * + * Where refcount is a number or -, and deps is a comma-separated list + * of depends or -. + */ +static const struct seq_operations modules_op = { + .start = m_start, + .next = m_next, + .stop = m_stop, + .show = m_show +}; + +/* + * This also sets the "private" pointer to non-NULL if the + * kernel pointers should be hidden (so you can just test + * "m->private" to see if you should keep the values private). + * + * We use the same logic as for /proc/kallsyms. + */ +static int modules_open(struct inode *inode, struct file *file) +{ + int err = seq_open(file, &modules_op); + + if (!err) { + struct seq_file *m = file->private_data; + + m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; + } + + return err; +} + +static const struct proc_ops modules_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, + .proc_open = modules_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = seq_release, +}; + +static int __init proc_modules_init(void) +{ + proc_create("modules", 0, NULL, &modules_proc_ops); + return 0; +} +module_init(proc_modules_init); -- cgit v1.3-18-gd494 From 01dc0386efb769056257410ba5754558384006a7 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Wed, 23 Feb 2022 13:02:14 +0100 Subject: module: Add CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC Add CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC to allow architectures to request having modules data in vmalloc area instead of module area. This is required on powerpc book3s/32 in order to set data non executable, because it is not possible to set executability on page basis, this is done per 256 Mbytes segments. The module area has exec right, vmalloc area has noexec. This can also be useful on other powerpc/32 in order to maximize the chance of code being close enough to kernel core to avoid branch trampolines. Cc: Jason Wessel Acked-by: Daniel Thompson Cc: Douglas Anderson Signed-off-by: Christophe Leroy [mcgrof: rebased in light of kernel/module/kdb.c move] Signed-off-by: Luis Chamberlain --- arch/Kconfig | 6 +++++ include/linux/module.h | 8 +++++++ kernel/module/internal.h | 3 +++ kernel/module/kdb.c | 10 ++++++-- kernel/module/main.c | 58 +++++++++++++++++++++++++++++++++++++++++++-- kernel/module/procfs.c | 8 +++++-- kernel/module/strict_rwx.c | 1 + kernel/module/tree_lookup.c | 8 +++++++ 8 files changed, 96 insertions(+), 6 deletions(-) (limited to 'kernel/module/procfs.c') diff --git a/arch/Kconfig b/arch/Kconfig index 29b0167c088b..24945cee808b 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -888,6 +888,12 @@ config MODULES_USE_ELF_REL Modules only use ELF REL relocations. Modules with ELF RELA relocations will give an error. +config ARCH_WANTS_MODULES_DATA_IN_VMALLOC + bool + help + For architectures like powerpc/32 which have constraints on module + allocation and need to allocate module data outside of module area. + config HAVE_IRQ_EXIT_ON_IRQ_STACK bool help diff --git a/include/linux/module.h b/include/linux/module.h index 5e2059f3afc7..46d4d5f2516e 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -422,6 +422,9 @@ struct module { /* Core layout: rbtree is accessed frequently, so keep together. */ struct module_layout core_layout __module_layout_align; struct module_layout init_layout; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + struct module_layout data_layout; +#endif /* Arch-specific module values */ struct mod_arch_specific arch; @@ -569,6 +572,11 @@ bool is_module_text_address(unsigned long addr); static inline bool within_module_core(unsigned long addr, const struct module *mod) { +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + if ((unsigned long)mod->data_layout.base <= addr && + addr < (unsigned long)mod->data_layout.base + mod->data_layout.size) + return true; +#endif return (unsigned long)mod->core_layout.base <= addr && addr < (unsigned long)mod->core_layout.base + mod->core_layout.size; } diff --git a/kernel/module/internal.h b/kernel/module/internal.h index 0aabbf5cbcd1..3e23bef5884d 100644 --- a/kernel/module/internal.h +++ b/kernel/module/internal.h @@ -20,7 +20,9 @@ /* Maximum number of characters written by module_flags() */ #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) +#ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC #define data_layout core_layout +#endif /* * Modules' sections will be aligned on page boundaries @@ -154,6 +156,7 @@ struct mod_tree_root { }; extern struct mod_tree_root mod_tree; +extern struct mod_tree_root mod_data_tree; #ifdef CONFIG_MODULES_TREE_LOOKUP void mod_tree_insert(struct module *mod); diff --git a/kernel/module/kdb.c b/kernel/module/kdb.c index a446c699db0a..f4317f92e189 100644 --- a/kernel/module/kdb.c +++ b/kernel/module/kdb.c @@ -26,8 +26,11 @@ int kdb_lsmod(int argc, const char **argv) if (mod->state == MODULE_STATE_UNFORMED) continue; - kdb_printf("%-20s%8u 0x%px ", mod->name, - mod->core_layout.size, (void *)mod); + kdb_printf("%-20s%8u", mod->name, mod->core_layout.size); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + kdb_printf("/%8u", mod->data_layout.size); +#endif + kdb_printf(" 0x%px ", (void *)mod); #ifdef CONFIG_MODULE_UNLOAD kdb_printf("%4d ", module_refcount(mod)); #endif @@ -38,6 +41,9 @@ int kdb_lsmod(int argc, const char **argv) else kdb_printf(" (Live)"); kdb_printf(" 0x%px", mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + kdb_printf("/0x%px", mod->data_layout.base); +#endif #ifdef CONFIG_MODULE_UNLOAD { diff --git a/kernel/module/main.c b/kernel/module/main.c index 78658283408d..84b828431dcb 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -78,6 +78,12 @@ struct mod_tree_root mod_tree __cacheline_aligned = { .addr_min = -1UL, }; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +struct mod_tree_root mod_data_tree __cacheline_aligned = { + .addr_min = -1UL, +}; +#endif + #define module_addr_min mod_tree.addr_min #define module_addr_max mod_tree.addr_max @@ -107,6 +113,9 @@ static void mod_update_bounds(struct module *mod) __mod_update_bounds(mod->core_layout.base, mod->core_layout.size, &mod_tree); if (mod->init_layout.size) __mod_update_bounds(mod->init_layout.base, mod->init_layout.size, &mod_tree); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + __mod_update_bounds(mod->data_layout.base, mod->data_layout.size, &mod_data_tree); +#endif } static void module_assert_mutex_or_preempt(void) @@ -940,6 +949,17 @@ static ssize_t show_coresize(struct module_attribute *mattr, static struct module_attribute modinfo_coresize = __ATTR(coresize, 0444, show_coresize, NULL); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +static ssize_t show_datasize(struct module_attribute *mattr, + struct module_kobject *mk, char *buffer) +{ + return sprintf(buffer, "%u\n", mk->mod->data_layout.size); +} + +static struct module_attribute modinfo_datasize = + __ATTR(datasize, 0444, show_datasize, NULL); +#endif + static ssize_t show_initsize(struct module_attribute *mattr, struct module_kobject *mk, char *buffer) { @@ -968,6 +988,9 @@ struct module_attribute *modinfo_attrs[] = { &modinfo_srcversion, &modinfo_initstate, &modinfo_coresize, +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + &modinfo_datasize, +#endif &modinfo_initsize, &modinfo_taint, #ifdef CONFIG_MODULE_UNLOAD @@ -1194,6 +1217,9 @@ static void free_module(struct module *mod) /* Finally, free the core (containing the module structure) */ module_memfree(mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + vfree(mod->data_layout.base); +#endif } void *__symbol_get(const char *symbol) @@ -2124,6 +2150,24 @@ static int move_module(struct module *mod, struct load_info *info) } else mod->init_layout.base = NULL; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + /* Do the allocs. */ + ptr = vmalloc(mod->data_layout.size); + /* + * The pointer to this block is stored in the module structure + * which is inside the block. Just mark it as not being a + * leak. + */ + kmemleak_not_leak(ptr); + if (!ptr) { + module_memfree(mod->core_layout.base); + module_memfree(mod->init_layout.base); + return -ENOMEM; + } + + memset(ptr, 0, mod->data_layout.size); + mod->data_layout.base = ptr; +#endif /* Transfer each section which specifies SHF_ALLOC */ pr_debug("final section addresses:\n"); for (i = 0; i < info->hdr->e_shnum; i++) { @@ -2299,6 +2343,9 @@ static void module_deallocate(struct module *mod, struct load_info *info) module_arch_freeing_init(mod); module_memfree(mod->init_layout.base); module_memfree(mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + vfree(mod->data_layout.base); +#endif } int __weak module_finalize(const Elf_Ehdr *hdr, @@ -3015,13 +3062,20 @@ bool is_module_address(unsigned long addr) struct module *__module_address(unsigned long addr) { struct module *mod; + struct mod_tree_root *tree; - if (addr < module_addr_min || addr > module_addr_max) + if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max) + tree = &mod_tree; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + else if (addr >= mod_data_tree.addr_min && addr <= mod_data_tree.addr_max) + tree = &mod_data_tree; +#endif + else return NULL; module_assert_mutex_or_preempt(); - mod = mod_find(addr, &mod_tree); + mod = mod_find(addr, tree); if (mod) { BUG_ON(!within_module(addr, mod)); if (mod->state == MODULE_STATE_UNFORMED) diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c index 2717e130788e..9a8f4f0f6329 100644 --- a/kernel/module/procfs.c +++ b/kernel/module/procfs.c @@ -67,13 +67,17 @@ static int m_show(struct seq_file *m, void *p) struct module *mod = list_entry(p, struct module, list); char buf[MODULE_FLAGS_BUF_SIZE]; void *value; + unsigned int size; /* We always ignore unformed modules. */ if (mod->state == MODULE_STATE_UNFORMED) return 0; - seq_printf(m, "%s %u", - mod->name, mod->init_layout.size + mod->core_layout.size); + size = mod->init_layout.size + mod->core_layout.size; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + size += mod->data_layout.size; +#endif + seq_printf(m, "%s %u", mod->name, size); print_unload_info(m, mod); /* Informative for users. */ diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c index fe3c10891407..14fbea66f12f 100644 --- a/kernel/module/strict_rwx.c +++ b/kernel/module/strict_rwx.c @@ -75,6 +75,7 @@ bool module_check_misalignment(const struct module *mod) return false; return layout_check_misalignment(&mod->core_layout) || + layout_check_misalignment(&mod->data_layout) || layout_check_misalignment(&mod->init_layout); } diff --git a/kernel/module/tree_lookup.c b/kernel/module/tree_lookup.c index 995fe68059db..8ec5cfd60496 100644 --- a/kernel/module/tree_lookup.c +++ b/kernel/module/tree_lookup.c @@ -83,6 +83,11 @@ void mod_tree_insert(struct module *mod) __mod_tree_insert(&mod->core_layout.mtn, &mod_tree); if (mod->init_layout.size) __mod_tree_insert(&mod->init_layout.mtn, &mod_tree); + +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + mod->data_layout.mtn.mod = mod; + __mod_tree_insert(&mod->data_layout.mtn, &mod_data_tree); +#endif } void mod_tree_remove_init(struct module *mod) @@ -95,6 +100,9 @@ void mod_tree_remove(struct module *mod) { __mod_tree_remove(&mod->core_layout.mtn, &mod_tree); mod_tree_remove_init(mod); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + __mod_tree_remove(&mod->data_layout.mtn, &mod_data_tree); +#endif } struct module *mod_find(unsigned long addr, struct mod_tree_root *tree) -- cgit v1.3-18-gd494