diff options
Diffstat (limited to 'kernel/module')
| -rw-r--r-- | kernel/module/kallsyms.c | 25 | ||||
| -rw-r--r-- | kernel/module/main.c | 46 |
2 files changed, 48 insertions, 23 deletions
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c index 62fb57bb9f16..bf65e0c3c86f 100644 --- a/kernel/module/kallsyms.c +++ b/kernel/module/kallsyms.c @@ -321,14 +321,15 @@ void * __weak dereference_module_function_descriptor(struct module *mod, * For kallsyms to ask for address resolution. NULL means not found. Careful * not to lock to avoid deadlock on oopses, simply disable preemption. */ -const char *module_address_lookup(unsigned long addr, - unsigned long *size, - unsigned long *offset, - char **modname, - const unsigned char **modbuildid, - char *namebuf) +int module_address_lookup(unsigned long addr, + unsigned long *size, + unsigned long *offset, + char **modname, + const unsigned char **modbuildid, + char *namebuf) { - const char *ret = NULL; + const char *sym; + int ret = 0; struct module *mod; preempt_disable(); @@ -344,12 +345,10 @@ const char *module_address_lookup(unsigned long addr, #endif } - ret = find_kallsyms_symbol(mod, addr, size, offset); - } - /* Make a copy in here where it's safe */ - if (ret) { - strscpy(namebuf, ret, KSYM_NAME_LEN); - ret = namebuf; + sym = find_kallsyms_symbol(mod, addr, size, offset); + + if (sym) + ret = strscpy(namebuf, sym, KSYM_NAME_LEN); } preempt_enable(); diff --git a/kernel/module/main.c b/kernel/module/main.c index d18a94b973e1..71396e297499 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -2166,6 +2166,8 @@ static int find_module_sections(struct module *mod, struct load_info *info) #endif #ifdef CONFIG_DEBUG_INFO_BTF_MODULES mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size); + mod->btf_base_data = any_section_objs(info, ".BTF.base", 1, + &mod->btf_base_data_size); #endif #ifdef CONFIG_JUMP_LABEL mod->jump_entries = section_objs(info, "__jump_table", @@ -2590,8 +2592,9 @@ static noinline int do_init_module(struct module *mod) } #ifdef CONFIG_DEBUG_INFO_BTF_MODULES - /* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */ + /* .BTF is not SHF_ALLOC and will get removed, so sanitize pointers */ mod->btf_data = NULL; + mod->btf_base_data = NULL; #endif /* * We want to free module_init, but be aware that kallsyms may be @@ -3101,7 +3104,7 @@ static bool idempotent(struct idempotent *u, const void *cookie) struct idempotent *existing; bool first; - u->ret = 0; + u->ret = -EINTR; u->cookie = cookie; init_completion(&u->complete); @@ -3137,7 +3140,7 @@ static int idempotent_complete(struct idempotent *u, int ret) hlist_for_each_entry_safe(pos, next, head, entry) { if (pos->cookie != cookie) continue; - hlist_del(&pos->entry); + hlist_del_init(&pos->entry); pos->ret = ret; complete(&pos->complete); } @@ -3145,6 +3148,28 @@ static int idempotent_complete(struct idempotent *u, int ret) return ret; } +/* + * Wait for the idempotent worker. + * + * If we get interrupted, we need to remove ourselves from the + * the idempotent list, and the completion may still come in. + * + * The 'idem_lock' protects against the race, and 'idem.ret' was + * initialized to -EINTR and is thus always the right return + * value even if the idempotent work then completes between + * the wait_for_completion and the cleanup. + */ +static int idempotent_wait_for_completion(struct idempotent *u) +{ + if (wait_for_completion_interruptible(&u->complete)) { + spin_lock(&idem_lock); + if (!hlist_unhashed(&u->entry)) + hlist_del(&u->entry); + spin_unlock(&idem_lock); + } + return u->ret; +} + static int init_module_from_file(struct file *f, const char __user * uargs, int flags) { struct load_info info = { }; @@ -3180,15 +3205,16 @@ static int idempotent_init_module(struct file *f, const char __user * uargs, int if (!f || !(f->f_mode & FMODE_READ)) return -EBADF; - /* See if somebody else is doing the operation? */ - if (idempotent(&idem, file_inode(f))) { - wait_for_completion(&idem.complete); - return idem.ret; + /* Are we the winners of the race and get to do this? */ + if (!idempotent(&idem, file_inode(f))) { + int ret = init_module_from_file(f, uargs, flags); + return idempotent_complete(&idem, ret); } - /* Otherwise, we'll do it and complete others */ - return idempotent_complete(&idem, - init_module_from_file(f, uargs, flags)); + /* + * Somebody else won the race and is loading the module. + */ + return idempotent_wait_for_completion(&idem); } SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |