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-rw-r--r--kernel/module/internal.h406
1 files changed, 406 insertions, 0 deletions
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
new file mode 100644
index 0000000000..c8b7b4dcf7
--- /dev/null
+++ b/kernel/module/internal.h
@@ -0,0 +1,406 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Module internals
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * Copyright (C) 2023 Luis Chamberlain <mcgrof@kernel.org>
+ */
+
+#include <linux/elf.h>
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/mm.h>
+
+#ifndef ARCH_SHF_SMALL
+#define ARCH_SHF_SMALL 0
+#endif
+
+/*
+ * Use highest 4 bits of sh_entsize to store the mod_mem_type of this
+ * section. This leaves 28 bits for offset on 32-bit systems, which is
+ * about 256 MiB (WARN_ON_ONCE if we exceed that).
+ */
+
+#define SH_ENTSIZE_TYPE_BITS 4
+#define SH_ENTSIZE_TYPE_SHIFT (BITS_PER_LONG - SH_ENTSIZE_TYPE_BITS)
+#define SH_ENTSIZE_TYPE_MASK ((1UL << SH_ENTSIZE_TYPE_BITS) - 1)
+#define SH_ENTSIZE_OFFSET_MASK ((1UL << (BITS_PER_LONG - SH_ENTSIZE_TYPE_BITS)) - 1)
+
+/* Maximum number of characters written by module_flags() */
+#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
+
+struct kernel_symbol {
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+ int value_offset;
+ int name_offset;
+ int namespace_offset;
+#else
+ unsigned long value;
+ const char *name;
+ const char *namespace;
+#endif
+};
+
+extern struct mutex module_mutex;
+extern struct list_head modules;
+
+extern struct module_attribute *modinfo_attrs[];
+extern size_t modinfo_attrs_count;
+
+/* Provided by the linker */
+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 s32 __start___kcrctab[];
+extern const s32 __start___kcrctab_gpl[];
+
+struct load_info {
+ const char *name;
+ /* pointer to module in temporary copy, freed at end of load_module() */
+ struct module *mod;
+ Elf_Ehdr *hdr;
+ unsigned long len;
+ Elf_Shdr *sechdrs;
+ char *secstrings, *strtab;
+ unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs;
+ bool sig_ok;
+#ifdef CONFIG_KALLSYMS
+ unsigned long mod_kallsyms_init_off;
+#endif
+#ifdef CONFIG_MODULE_DECOMPRESS
+#ifdef CONFIG_MODULE_STATS
+ unsigned long compressed_len;
+#endif
+ struct page **pages;
+ unsigned int max_pages;
+ unsigned int used_pages;
+#endif
+ struct {
+ unsigned int sym, str, mod, vers, info, pcpu;
+ } index;
+};
+
+enum mod_license {
+ NOT_GPL_ONLY,
+ GPL_ONLY,
+};
+
+struct find_symbol_arg {
+ /* Input */
+ const char *name;
+ bool gplok;
+ bool warn;
+
+ /* Output */
+ struct module *owner;
+ const s32 *crc;
+ const struct kernel_symbol *sym;
+ enum mod_license license;
+};
+
+int mod_verify_sig(const void *mod, struct load_info *info);
+int try_to_force_load(struct module *mod, const char *reason);
+bool find_symbol(struct find_symbol_arg *fsa);
+struct module *find_module_all(const char *name, size_t len, bool even_unformed);
+int cmp_name(const void *name, const void *sym);
+long module_get_offset_and_type(struct module *mod, enum mod_mem_type type,
+ Elf_Shdr *sechdr, unsigned int section);
+char *module_flags(struct module *mod, char *buf, bool show_state);
+size_t module_flags_taint(unsigned long taints, char *buf);
+
+char *module_next_tag_pair(char *string, unsigned long *secsize);
+
+#define for_each_modinfo_entry(entry, info, name) \
+ for (entry = get_modinfo(info, name); entry; entry = get_next_modinfo(info, name, entry))
+
+static inline void module_assert_mutex_or_preempt(void)
+{
+#ifdef CONFIG_LOCKDEP
+ if (unlikely(!debug_locks))
+ return;
+
+ WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
+ !lockdep_is_held(&module_mutex));
+#endif
+}
+
+static inline unsigned long kernel_symbol_value(const struct kernel_symbol *sym)
+{
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+ return (unsigned long)offset_to_ptr(&sym->value_offset);
+#else
+ return sym->value;
+#endif
+}
+
+#ifdef CONFIG_LIVEPATCH
+int copy_module_elf(struct module *mod, struct load_info *info);
+void free_module_elf(struct module *mod);
+#else /* !CONFIG_LIVEPATCH */
+static inline int copy_module_elf(struct module *mod, struct load_info *info)
+{
+ return 0;
+}
+
+static inline void free_module_elf(struct module *mod) { }
+#endif /* CONFIG_LIVEPATCH */
+
+static inline bool set_livepatch_module(struct module *mod)
+{
+#ifdef CONFIG_LIVEPATCH
+ mod->klp = true;
+ return true;
+#else
+ return false;
+#endif
+}
+
+/**
+ * enum fail_dup_mod_reason - state at which a duplicate module was detected
+ *
+ * @FAIL_DUP_MOD_BECOMING: the module is read properly, passes all checks but
+ * we've determined that another module with the same name is already loaded
+ * or being processed on our &modules list. This happens on early_mod_check()
+ * right before layout_and_allocate(). The kernel would have already
+ * vmalloc()'d space for the entire module through finit_module(). If
+ * decompression was used two vmap() spaces were used. These failures can
+ * happen when userspace has not seen the module present on the kernel and
+ * tries to load the module multiple times at same time.
+ * @FAIL_DUP_MOD_LOAD: the module has been read properly, passes all validation
+ * checks and the kernel determines that the module was unique and because
+ * of this allocated yet another private kernel copy of the module space in
+ * layout_and_allocate() but after this determined in add_unformed_module()
+ * that another module with the same name is already loaded or being processed.
+ * These failures should be mitigated as much as possible and are indicative
+ * of really fast races in loading modules. Without module decompression
+ * they waste twice as much vmap space. With module decompression three
+ * times the module's size vmap space is wasted.
+ */
+enum fail_dup_mod_reason {
+ FAIL_DUP_MOD_BECOMING = 0,
+ FAIL_DUP_MOD_LOAD,
+};
+
+#ifdef CONFIG_MODULE_DEBUGFS
+extern struct dentry *mod_debugfs_root;
+#endif
+
+#ifdef CONFIG_MODULE_STATS
+
+#define mod_stat_add_long(count, var) atomic_long_add(count, var)
+#define mod_stat_inc(name) atomic_inc(name)
+
+extern atomic_long_t total_mod_size;
+extern atomic_long_t total_text_size;
+extern atomic_long_t invalid_kread_bytes;
+extern atomic_long_t invalid_decompress_bytes;
+
+extern atomic_t modcount;
+extern atomic_t failed_kreads;
+extern atomic_t failed_decompress;
+struct mod_fail_load {
+ struct list_head list;
+ char name[MODULE_NAME_LEN];
+ atomic_long_t count;
+ unsigned long dup_fail_mask;
+};
+
+int try_add_failed_module(const char *name, enum fail_dup_mod_reason reason);
+void mod_stat_bump_invalid(struct load_info *info, int flags);
+void mod_stat_bump_becoming(struct load_info *info, int flags);
+
+#else
+
+#define mod_stat_add_long(name, var)
+#define mod_stat_inc(name)
+
+static inline int try_add_failed_module(const char *name,
+ enum fail_dup_mod_reason reason)
+{
+ return 0;
+}
+
+static inline void mod_stat_bump_invalid(struct load_info *info, int flags)
+{
+}
+
+static inline void mod_stat_bump_becoming(struct load_info *info, int flags)
+{
+}
+
+#endif /* CONFIG_MODULE_STATS */
+
+#ifdef CONFIG_MODULE_DEBUG_AUTOLOAD_DUPS
+bool kmod_dup_request_exists_wait(char *module_name, bool wait, int *dup_ret);
+void kmod_dup_request_announce(char *module_name, int ret);
+#else
+static inline bool kmod_dup_request_exists_wait(char *module_name, bool wait, int *dup_ret)
+{
+ return false;
+}
+
+static inline void kmod_dup_request_announce(char *module_name, int ret)
+{
+}
+#endif
+
+#ifdef CONFIG_MODULE_UNLOAD_TAINT_TRACKING
+struct mod_unload_taint {
+ struct list_head list;
+ char name[MODULE_NAME_LEN];
+ unsigned long taints;
+ u64 count;
+};
+
+int try_add_tainted_module(struct module *mod);
+void print_unloaded_tainted_modules(void);
+#else /* !CONFIG_MODULE_UNLOAD_TAINT_TRACKING */
+static inline int try_add_tainted_module(struct module *mod)
+{
+ return 0;
+}
+
+static inline void print_unloaded_tainted_modules(void)
+{
+}
+#endif /* CONFIG_MODULE_UNLOAD_TAINT_TRACKING */
+
+#ifdef CONFIG_MODULE_DECOMPRESS
+int module_decompress(struct load_info *info, const void *buf, size_t size);
+void module_decompress_cleanup(struct load_info *info);
+#else
+static inline int module_decompress(struct load_info *info,
+ const void *buf, size_t size)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline void module_decompress_cleanup(struct load_info *info)
+{
+}
+#endif
+
+struct mod_tree_root {
+#ifdef CONFIG_MODULES_TREE_LOOKUP
+ struct latch_tree_root root;
+#endif
+ unsigned long addr_min;
+ unsigned long addr_max;
+#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
+ unsigned long data_addr_min;
+ unsigned long data_addr_max;
+#endif
+};
+
+extern struct mod_tree_root mod_tree;
+
+#ifdef CONFIG_MODULES_TREE_LOOKUP
+void mod_tree_insert(struct module *mod);
+void mod_tree_remove_init(struct module *mod);
+void mod_tree_remove(struct module *mod);
+struct module *mod_find(unsigned long addr, struct mod_tree_root *tree);
+#else /* !CONFIG_MODULES_TREE_LOOKUP */
+
+static inline void mod_tree_insert(struct module *mod) { }
+static inline void mod_tree_remove_init(struct module *mod) { }
+static inline void mod_tree_remove(struct module *mod) { }
+static inline struct module *mod_find(unsigned long addr, struct mod_tree_root *tree)
+{
+ struct module *mod;
+
+ list_for_each_entry_rcu(mod, &modules, list,
+ lockdep_is_held(&module_mutex)) {
+ if (within_module(addr, mod))
+ return mod;
+ }
+
+ return NULL;
+}
+#endif /* CONFIG_MODULES_TREE_LOOKUP */
+
+void module_enable_ro(const struct module *mod, bool after_init);
+void module_enable_nx(const struct module *mod);
+void module_enable_x(const struct module *mod);
+int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+ char *secstrings, struct module *mod);
+
+#ifdef CONFIG_MODULE_SIG
+int module_sig_check(struct load_info *info, int flags);
+#else /* !CONFIG_MODULE_SIG */
+static inline int module_sig_check(struct load_info *info, int flags)
+{
+ return 0;
+}
+#endif /* !CONFIG_MODULE_SIG */
+
+#ifdef CONFIG_DEBUG_KMEMLEAK
+void kmemleak_load_module(const struct module *mod, const struct load_info *info);
+#else /* !CONFIG_DEBUG_KMEMLEAK */
+static inline void kmemleak_load_module(const struct module *mod,
+ const struct load_info *info) { }
+#endif /* CONFIG_DEBUG_KMEMLEAK */
+
+#ifdef CONFIG_KALLSYMS
+void init_build_id(struct module *mod, const struct load_info *info);
+void layout_symtab(struct module *mod, struct load_info *info);
+void add_kallsyms(struct module *mod, const struct load_info *info);
+
+static inline bool sect_empty(const Elf_Shdr *sect)
+{
+ return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
+}
+#else /* !CONFIG_KALLSYMS */
+static inline void init_build_id(struct module *mod, const struct load_info *info) { }
+static inline void layout_symtab(struct module *mod, struct load_info *info) { }
+static inline void add_kallsyms(struct module *mod, const struct load_info *info) { }
+#endif /* CONFIG_KALLSYMS */
+
+#ifdef CONFIG_SYSFS
+int mod_sysfs_setup(struct module *mod, const struct load_info *info,
+ struct kernel_param *kparam, unsigned int num_params);
+void mod_sysfs_teardown(struct module *mod);
+void init_param_lock(struct module *mod);
+#else /* !CONFIG_SYSFS */
+static inline int mod_sysfs_setup(struct module *mod,
+ const struct load_info *info,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ return 0;
+}
+
+static inline void mod_sysfs_teardown(struct module *mod) { }
+static inline void init_param_lock(struct module *mod) { }
+#endif /* CONFIG_SYSFS */
+
+#ifdef CONFIG_MODVERSIONS
+int check_version(const struct load_info *info,
+ const char *symname, struct module *mod, const s32 *crc);
+void module_layout(struct module *mod, struct modversion_info *ver, struct kernel_param *kp,
+ struct kernel_symbol *ks, struct tracepoint * const *tp);
+int check_modstruct_version(const struct load_info *info, struct module *mod);
+int same_magic(const char *amagic, const char *bmagic, bool has_crcs);
+#else /* !CONFIG_MODVERSIONS */
+static inline int check_version(const struct load_info *info,
+ const char *symname,
+ struct module *mod,
+ const s32 *crc)
+{
+ return 1;
+}
+
+static inline int check_modstruct_version(const struct load_info *info,
+ struct module *mod)
+{
+ return 1;
+}
+
+static inline int same_magic(const char *amagic, const char *bmagic, bool has_crcs)
+{
+ return strcmp(amagic, bmagic) == 0;
+}
+#endif /* CONFIG_MODVERSIONS */