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Diffstat (limited to 'kernel')
-rw-r--r--kernel/module.c367
-rw-r--r--kernel/sys_ni.c1
2 files changed, 220 insertions, 148 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 6e48c3a4359..6d2c4e4ca1f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -21,6 +21,7 @@
#include <linux/ftrace_event.h>
#include <linux/init.h>
#include <linux/kallsyms.h>
+#include <linux/file.h>
#include <linux/fs.h>
#include <linux/sysfs.h>
#include <linux/kernel.h>
@@ -2425,18 +2426,17 @@ static inline void kmemleak_load_module(const struct module *mod,
#endif
#ifdef CONFIG_MODULE_SIG
-static int module_sig_check(struct load_info *info,
- const void *mod, unsigned long *_len)
+static int module_sig_check(struct load_info *info)
{
int err = -ENOKEY;
- unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
- unsigned long len = *_len;
+ const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
+ const void *mod = info->hdr;
- if (len > markerlen &&
- memcmp(mod + len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
+ if (info->len > markerlen &&
+ memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
/* We truncate the module to discard the signature */
- *_len -= markerlen;
- err = mod_verify_sig(mod, _len);
+ info->len -= markerlen;
+ err = mod_verify_sig(mod, &info->len);
}
if (!err) {
@@ -2454,59 +2454,97 @@ static int module_sig_check(struct load_info *info,
return err;
}
#else /* !CONFIG_MODULE_SIG */
-static int module_sig_check(struct load_info *info,
- void *mod, unsigned long *len)
+static int module_sig_check(struct load_info *info)
{
return 0;
}
#endif /* !CONFIG_MODULE_SIG */
-/* Sets info->hdr, info->len and info->sig_ok. */
-static int copy_and_check(struct load_info *info,
- const void __user *umod, unsigned long len,
- const char __user *uargs)
+/* Sanity checks against invalid binaries, wrong arch, weird elf version. */
+static int elf_header_check(struct load_info *info)
{
- int err;
- Elf_Ehdr *hdr;
+ if (info->len < sizeof(*(info->hdr)))
+ return -ENOEXEC;
+
+ if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
+ || info->hdr->e_type != ET_REL
+ || !elf_check_arch(info->hdr)
+ || info->hdr->e_shentsize != sizeof(Elf_Shdr))
+ return -ENOEXEC;
+
+ if (info->hdr->e_shoff >= info->len
+ || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
+ info->len - info->hdr->e_shoff))
+ return -ENOEXEC;
- if (len < sizeof(*hdr))
+ return 0;
+}
+
+/* Sets info->hdr and info->len. */
+static int copy_module_from_user(const void __user *umod, unsigned long len,
+ struct load_info *info)
+{
+ info->len = len;
+ if (info->len < sizeof(*(info->hdr)))
return -ENOEXEC;
/* Suck in entire file: we'll want most of it. */
- if ((hdr = vmalloc(len)) == NULL)
+ info->hdr = vmalloc(info->len);
+ if (!info->hdr)
return -ENOMEM;
- if (copy_from_user(hdr, umod, len) != 0) {
- err = -EFAULT;
- goto free_hdr;
+ if (copy_from_user(info->hdr, umod, info->len) != 0) {
+ vfree(info->hdr);
+ return -EFAULT;
}
- err = module_sig_check(info, hdr, &len);
+ return 0;
+}
+
+/* Sets info->hdr and info->len. */
+static int copy_module_from_fd(int fd, struct load_info *info)
+{
+ struct file *file;
+ int err;
+ struct kstat stat;
+ loff_t pos;
+ ssize_t bytes = 0;
+
+ file = fget(fd);
+ if (!file)
+ return -ENOEXEC;
+
+ err = vfs_getattr(file->f_vfsmnt, file->f_dentry, &stat);
if (err)
- goto free_hdr;
+ goto out;
- /* Sanity checks against insmoding binaries or wrong arch,
- weird elf version */
- if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
- || hdr->e_type != ET_REL
- || !elf_check_arch(hdr)
- || hdr->e_shentsize != sizeof(Elf_Shdr)) {
- err = -ENOEXEC;
- goto free_hdr;
+ if (stat.size > INT_MAX) {
+ err = -EFBIG;
+ goto out;
}
-
- if (hdr->e_shoff >= len ||
- hdr->e_shnum * sizeof(Elf_Shdr) > len - hdr->e_shoff) {
- err = -ENOEXEC;
- goto free_hdr;
+ info->hdr = vmalloc(stat.size);
+ if (!info->hdr) {
+ err = -ENOMEM;
+ goto out;
}
- info->hdr = hdr;
- info->len = len;
- return 0;
+ pos = 0;
+ while (pos < stat.size) {
+ bytes = kernel_read(file, pos, (char *)(info->hdr) + pos,
+ stat.size - pos);
+ if (bytes < 0) {
+ vfree(info->hdr);
+ err = bytes;
+ goto out;
+ }
+ if (bytes == 0)
+ break;
+ pos += bytes;
+ }
+ info->len = pos;
-free_hdr:
- vfree(hdr);
+out:
+ fput(file);
return err;
}
@@ -2945,33 +2983,123 @@ static bool finished_loading(const char *name)
return ret;
}
+/* Call module constructors. */
+static void do_mod_ctors(struct module *mod)
+{
+#ifdef CONFIG_CONSTRUCTORS
+ unsigned long i;
+
+ for (i = 0; i < mod->num_ctors; i++)
+ mod->ctors[i]();
+#endif
+}
+
+/* This is where the real work happens */
+static int do_init_module(struct module *mod)
+{
+ int ret = 0;
+
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_COMING, mod);
+
+ /* Set RO and NX regions for core */
+ set_section_ro_nx(mod->module_core,
+ mod->core_text_size,
+ mod->core_ro_size,
+ mod->core_size);
+
+ /* Set RO and NX regions for init */
+ set_section_ro_nx(mod->module_init,
+ mod->init_text_size,
+ mod->init_ro_size,
+ mod->init_size);
+
+ do_mod_ctors(mod);
+ /* Start the module */
+ if (mod->init != NULL)
+ ret = do_one_initcall(mod->init);
+ if (ret < 0) {
+ /* Init routine failed: abort. Try to protect us from
+ buggy refcounters. */
+ mod->state = MODULE_STATE_GOING;
+ synchronize_sched();
+ module_put(mod);
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_GOING, mod);
+ free_module(mod);
+ wake_up_all(&module_wq);
+ return ret;
+ }
+ if (ret > 0) {
+ printk(KERN_WARNING
+"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
+"%s: loading module anyway...\n",
+ __func__, mod->name, ret,
+ __func__);
+ dump_stack();
+ }
+
+ /* Now it's a first class citizen! */
+ mod->state = MODULE_STATE_LIVE;
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_LIVE, mod);
+
+ /* We need to finish all async code before the module init sequence is done */
+ async_synchronize_full();
+
+ mutex_lock(&module_mutex);
+ /* Drop initial reference. */
+ module_put(mod);
+ trim_init_extable(mod);
+#ifdef CONFIG_KALLSYMS
+ mod->num_symtab = mod->core_num_syms;
+ mod->symtab = mod->core_symtab;
+ mod->strtab = mod->core_strtab;
+#endif
+ unset_module_init_ro_nx(mod);
+ module_free(mod, mod->module_init);
+ mod->module_init = NULL;
+ mod->init_size = 0;
+ mod->init_ro_size = 0;
+ mod->init_text_size = 0;
+ mutex_unlock(&module_mutex);
+ wake_up_all(&module_wq);
+
+ return 0;
+}
+
+static int may_init_module(void)
+{
+ if (!capable(CAP_SYS_MODULE) || modules_disabled)
+ return -EPERM;
+
+ return 0;
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
-static struct module *load_module(void __user *umod,
- unsigned long len,
- const char __user *uargs)
+static int load_module(struct load_info *info, const char __user *uargs)
{
- struct load_info info = { NULL, };
struct module *mod, *old;
long err;
- pr_debug("load_module: umod=%p, len=%lu, uargs=%p\n",
- umod, len, uargs);
+ err = module_sig_check(info);
+ if (err)
+ goto free_copy;
- /* Copy in the blobs from userspace, check they are vaguely sane. */
- err = copy_and_check(&info, umod, len, uargs);
+ err = elf_header_check(info);
if (err)
- return ERR_PTR(err);
+ goto free_copy;
/* Figure out module layout, and allocate all the memory. */
- mod = layout_and_allocate(&info);
+ mod = layout_and_allocate(info);
if (IS_ERR(mod)) {
err = PTR_ERR(mod);
goto free_copy;
}
#ifdef CONFIG_MODULE_SIG
- mod->sig_ok = info.sig_ok;
+ mod->sig_ok = info->sig_ok;
if (!mod->sig_ok)
add_taint_module(mod, TAINT_FORCED_MODULE);
#endif
@@ -2983,25 +3111,25 @@ static struct module *load_module(void __user *umod,
/* Now we've got everything in the final locations, we can
* find optional sections. */
- find_module_sections(mod, &info);
+ find_module_sections(mod, info);
err = check_module_license_and_versions(mod);
if (err)
goto free_unload;
/* Set up MODINFO_ATTR fields */
- setup_modinfo(mod, &info);
+ setup_modinfo(mod, info);
/* Fix up syms, so that st_value is a pointer to location. */
- err = simplify_symbols(mod, &info);
+ err = simplify_symbols(mod, info);
if (err < 0)
goto free_modinfo;
- err = apply_relocations(mod, &info);
+ err = apply_relocations(mod, info);
if (err < 0)
goto free_modinfo;
- err = post_relocation(mod, &info);
+ err = post_relocation(mod, info);
if (err < 0)
goto free_modinfo;
@@ -3041,14 +3169,14 @@ again:
}
/* This has to be done once we're sure module name is unique. */
- dynamic_debug_setup(info.debug, info.num_debug);
+ dynamic_debug_setup(info->debug, info->num_debug);
/* Find duplicate symbols */
err = verify_export_symbols(mod);
if (err < 0)
goto ddebug;
- module_bug_finalize(info.hdr, info.sechdrs, mod);
+ module_bug_finalize(info->hdr, info->sechdrs, mod);
list_add_rcu(&mod->list, &modules);
mutex_unlock(&module_mutex);
@@ -3059,16 +3187,17 @@ again:
goto unlink;
/* Link in to syfs. */
- err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp);
+ err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
if (err < 0)
goto unlink;
/* Get rid of temporary copy. */
- free_copy(&info);
+ free_copy(info);
/* Done! */
trace_module_load(mod);
- return mod;
+
+ return do_init_module(mod);
unlink:
mutex_lock(&module_mutex);
@@ -3077,7 +3206,7 @@ again:
module_bug_cleanup(mod);
wake_up_all(&module_wq);
ddebug:
- dynamic_debug_remove(info.debug);
+ dynamic_debug_remove(info->debug);
unlock:
mutex_unlock(&module_mutex);
synchronize_sched();
@@ -3089,106 +3218,48 @@ again:
free_unload:
module_unload_free(mod);
free_module:
- module_deallocate(mod, &info);
+ module_deallocate(mod, info);
free_copy:
- free_copy(&info);
- return ERR_PTR(err);
-}
-
-/* Call module constructors. */
-static void do_mod_ctors(struct module *mod)
-{
-#ifdef CONFIG_CONSTRUCTORS
- unsigned long i;
-
- for (i = 0; i < mod->num_ctors; i++)
- mod->ctors[i]();
-#endif
+ free_copy(info);
+ return err;
}
-/* This is where the real work happens */
SYSCALL_DEFINE3(init_module, void __user *, umod,
unsigned long, len, const char __user *, uargs)
{
- struct module *mod;
- int ret = 0;
-
- /* Must have permission */
- if (!capable(CAP_SYS_MODULE) || modules_disabled)
- return -EPERM;
+ int err;
+ struct load_info info = { };
- /* Do all the hard work */
- mod = load_module(umod, len, uargs);
- if (IS_ERR(mod))
- return PTR_ERR(mod);
+ err = may_init_module();
+ if (err)
+ return err;
- blocking_notifier_call_chain(&module_notify_list,
- MODULE_STATE_COMING, mod);
+ pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
+ umod, len, uargs);
- /* Set RO and NX regions for core */
- set_section_ro_nx(mod->module_core,
- mod->core_text_size,
- mod->core_ro_size,
- mod->core_size);
+ err = copy_module_from_user(umod, len, &info);
+ if (err)
+ return err;
- /* Set RO and NX regions for init */
- set_section_ro_nx(mod->module_init,
- mod->init_text_size,
- mod->init_ro_size,
- mod->init_size);
+ return load_module(&info, uargs);
+}
- do_mod_ctors(mod);
- /* Start the module */
- if (mod->init != NULL)
- ret = do_one_initcall(mod->init);
- if (ret < 0) {
- /* Init routine failed: abort. Try to protect us from
- buggy refcounters. */
- mod->state = MODULE_STATE_GOING;
- synchronize_sched();
- module_put(mod);
- blocking_notifier_call_chain(&module_notify_list,
- MODULE_STATE_GOING, mod);
- free_module(mod);
- wake_up_all(&module_wq);
- return ret;
- }
- if (ret > 0) {
- printk(KERN_WARNING
-"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
-"%s: loading module anyway...\n",
- __func__, mod->name, ret,
- __func__);
- dump_stack();
- }
+SYSCALL_DEFINE2(finit_module, int, fd, const char __user *, uargs)
+{
+ int err;
+ struct load_info info = { };
- /* Now it's a first class citizen! */
- mod->state = MODULE_STATE_LIVE;
- blocking_notifier_call_chain(&module_notify_list,
- MODULE_STATE_LIVE, mod);
+ err = may_init_module();
+ if (err)
+ return err;
- /* We need to finish all async code before the module init sequence is done */
- async_synchronize_full();
+ pr_debug("finit_module: fd=%d, uargs=%p\n", fd, uargs);
- mutex_lock(&module_mutex);
- /* Drop initial reference. */
- module_put(mod);
- trim_init_extable(mod);
-#ifdef CONFIG_KALLSYMS
- mod->num_symtab = mod->core_num_syms;
- mod->symtab = mod->core_symtab;
- mod->strtab = mod->core_strtab;
-#endif
- unset_module_init_ro_nx(mod);
- module_free(mod, mod->module_init);
- mod->module_init = NULL;
- mod->init_size = 0;
- mod->init_ro_size = 0;
- mod->init_text_size = 0;
- mutex_unlock(&module_mutex);
- wake_up_all(&module_wq);
+ err = copy_module_from_fd(fd, &info);
+ if (err)
+ return err;
- return 0;
+ return load_module(&info, uargs);
}
static inline int within(unsigned long addr, void *start, unsigned long size)
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index dbff751e408..395084d4ce1 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -25,6 +25,7 @@ cond_syscall(sys_swapoff);
cond_syscall(sys_kexec_load);
cond_syscall(compat_sys_kexec_load);
cond_syscall(sys_init_module);
+cond_syscall(sys_finit_module);
cond_syscall(sys_delete_module);
cond_syscall(sys_socketpair);
cond_syscall(sys_bind);