#include <linux/string.h>
#include <linux/init.h>
#include <linux/pagemap.h>
+#include <linux/perf_counter.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>
#include <linux/key.h>
#include <linux/proc_fs.h>
#include <linux/mount.h>
#include <linux/security.h>
+#include <linux/ima.h>
#include <linux/syscalls.h>
#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
#include <linux/tracehook.h>
#include <linux/kmod.h>
#include <linux/fsnotify.h>
+#include <linux/fs_struct.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
static LIST_HEAD(formats);
static DEFINE_RWLOCK(binfmt_lock);
-int register_binfmt(struct linux_binfmt * fmt)
+int __register_binfmt(struct linux_binfmt * fmt, int insert)
{
if (!fmt)
return -EINVAL;
write_lock(&binfmt_lock);
- list_add(&fmt->lh, &formats);
+ insert ? list_add(&fmt->lh, &formats) :
+ list_add_tail(&fmt->lh, &formats);
write_unlock(&binfmt_lock);
return 0;
}
-EXPORT_SYMBOL(register_binfmt);
+EXPORT_SYMBOL(__register_binfmt);
void unregister_binfmt(struct linux_binfmt * fmt)
{
*
* Also note that we take the address to load from from the file itself.
*/
-asmlinkage long sys_uselib(const char __user * library)
+SYSCALL_DEFINE1(uselib, const char __user *, library)
{
struct file *file;
- struct nameidata nd;
char *tmp = getname(library);
int error = PTR_ERR(tmp);
- if (!IS_ERR(tmp)) {
- error = path_lookup_open(AT_FDCWD, tmp,
- LOOKUP_FOLLOW, &nd,
- FMODE_READ|FMODE_EXEC);
- putname(tmp);
- }
- if (error)
+ if (IS_ERR(tmp))
+ goto out;
+
+ file = do_filp_open(AT_FDCWD, tmp,
+ O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
+ MAY_READ | MAY_EXEC | MAY_OPEN);
+ putname(tmp);
+ error = PTR_ERR(file);
+ if (IS_ERR(file))
goto out;
error = -EINVAL;
- if (!S_ISREG(nd.path.dentry->d_inode->i_mode))
+ if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
goto exit;
error = -EACCES;
- if (nd.path.mnt->mnt_flags & MNT_NOEXEC)
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
goto exit;
- error = inode_permission(nd.path.dentry->d_inode,
- MAY_READ | MAY_EXEC | MAY_OPEN);
- if (error)
- goto exit;
-
- file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
- error = PTR_ERR(file);
- if (IS_ERR(file))
- goto out;
-
fsnotify_open(file->f_path.dentry);
error = -ENOEXEC;
}
read_unlock(&binfmt_lock);
}
+exit:
fput(file);
out:
return error;
-exit:
- release_open_intent(&nd);
- path_put(&nd.path);
- goto out;
}
#ifdef CONFIG_MMU
struct file *open_exec(const char *name)
{
- struct nameidata nd;
struct file *file;
int err;
- err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd,
- FMODE_READ|FMODE_EXEC);
- if (err)
+ file = do_filp_open(AT_FDCWD, name,
+ O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
+ MAY_EXEC | MAY_OPEN);
+ if (IS_ERR(file))
goto out;
err = -EACCES;
- if (!S_ISREG(nd.path.dentry->d_inode->i_mode))
- goto out_path_put;
-
- if (nd.path.mnt->mnt_flags & MNT_NOEXEC)
- goto out_path_put;
-
- err = inode_permission(nd.path.dentry->d_inode, MAY_EXEC | MAY_OPEN);
- if (err)
- goto out_path_put;
+ if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
+ goto exit;
- file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
- if (IS_ERR(file))
- return file;
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+ goto exit;
fsnotify_open(file->f_path.dentry);
err = deny_write_access(file);
- if (err) {
- fput(file);
- goto out;
- }
+ if (err)
+ goto exit;
+out:
return file;
- out_path_put:
- release_open_intent(&nd);
- path_put(&nd.path);
- out:
+exit:
+ fput(file);
return ERR_PTR(err);
}
EXPORT_SYMBOL(open_exec);
-int kernel_read(struct file *file, unsigned long offset,
- char *addr, unsigned long count)
+int kernel_read(struct file *file, loff_t offset,
+ char *addr, unsigned long count)
{
mm_segment_t old_fs;
loff_t pos = offset;
task_lock(tsk);
strlcpy(tsk->comm, buf, sizeof(tsk->comm));
task_unlock(tsk);
+ perf_counter_comm(tsk);
}
int flush_old_exec(struct linux_binprm * bprm)
current->personality &= ~bprm->per_clear;
+ /*
+ * Flush performance counters when crossing a
+ * security domain:
+ */
+ if (!get_dumpable(current->mm))
+ perf_counter_exit_task(current);
+
/* An exec changes our domain. We are no longer part of the thread
group */
EXPORT_SYMBOL(flush_old_exec);
/*
+ * Prepare credentials and lock ->cred_guard_mutex.
+ * install_exec_creds() commits the new creds and drops the lock.
+ * Or, if exec fails before, free_bprm() should release ->cred and
+ * and unlock.
+ */
+int prepare_bprm_creds(struct linux_binprm *bprm)
+{
+ if (mutex_lock_interruptible(¤t->cred_guard_mutex))
+ return -ERESTARTNOINTR;
+
+ bprm->cred = prepare_exec_creds();
+ if (likely(bprm->cred))
+ return 0;
+
+ mutex_unlock(¤t->cred_guard_mutex);
+ return -ENOMEM;
+}
+
+void free_bprm(struct linux_binprm *bprm)
+{
+ free_arg_pages(bprm);
+ if (bprm->cred) {
+ mutex_unlock(¤t->cred_guard_mutex);
+ abort_creds(bprm->cred);
+ }
+ kfree(bprm);
+}
+
+/*
* install the new credentials for this executable
*/
void install_exec_creds(struct linux_binprm *bprm)
commit_creds(bprm->cred);
bprm->cred = NULL;
-
- /* cred_exec_mutex must be held at least to this point to prevent
+ /*
+ * cred_guard_mutex must be held at least to this point to prevent
* ptrace_attach() from altering our determination of the task's
- * credentials; any time after this it may be unlocked */
-
+ * credentials; any time after this it may be unlocked.
+ */
security_bprm_committed_creds(bprm);
+ mutex_unlock(¤t->cred_guard_mutex);
}
EXPORT_SYMBOL(install_exec_creds);
/*
* determine how safe it is to execute the proposed program
- * - the caller must hold current->cred_exec_mutex to protect against
+ * - the caller must hold current->cred_guard_mutex to protect against
* PTRACE_ATTACH
*/
-void check_unsafe_exec(struct linux_binprm *bprm)
+int check_unsafe_exec(struct linux_binprm *bprm)
{
- struct task_struct *p = current;
+ struct task_struct *p = current, *t;
+ unsigned n_fs;
+ int res = 0;
bprm->unsafe = tracehook_unsafe_exec(p);
- if (atomic_read(&p->fs->count) > 1 ||
- atomic_read(&p->files->count) > 1 ||
- atomic_read(&p->sighand->count) > 1)
+ n_fs = 1;
+ write_lock(&p->fs->lock);
+ rcu_read_lock();
+ for (t = next_thread(p); t != p; t = next_thread(t)) {
+ if (t->fs == p->fs)
+ n_fs++;
+ }
+ rcu_read_unlock();
+
+ if (p->fs->users > n_fs) {
bprm->unsafe |= LSM_UNSAFE_SHARE;
+ } else {
+ res = -EAGAIN;
+ if (!p->fs->in_exec) {
+ p->fs->in_exec = 1;
+ res = 1;
+ }
+ }
+ write_unlock(&p->fs->lock);
+
+ return res;
}
/*
retval = security_bprm_check(bprm);
if (retval)
return retval;
+ retval = ima_bprm_check(bprm);
+ if (retval)
+ return retval;
/* kernel module loader fixup */
/* so we don't try to load run modprobe in kernel space. */
EXPORT_SYMBOL(search_binary_handler);
-void free_bprm(struct linux_binprm *bprm)
-{
- free_arg_pages(bprm);
- if (bprm->cred)
- abort_creds(bprm->cred);
- kfree(bprm);
-}
-
/*
* sys_execve() executes a new program.
*/
struct linux_binprm *bprm;
struct file *file;
struct files_struct *displaced;
+ bool clear_in_exec;
int retval;
retval = unshare_files(&displaced);
if (!bprm)
goto out_files;
- retval = mutex_lock_interruptible(¤t->cred_exec_mutex);
- if (retval < 0)
+ retval = prepare_bprm_creds(bprm);
+ if (retval)
goto out_free;
- retval = -ENOMEM;
- bprm->cred = prepare_exec_creds();
- if (!bprm->cred)
- goto out_unlock;
- check_unsafe_exec(bprm);
+ retval = check_unsafe_exec(bprm);
+ if (retval < 0)
+ goto out_free;
+ clear_in_exec = retval;
+ current->in_execve = 1;
file = open_exec(filename);
retval = PTR_ERR(file);
if (IS_ERR(file))
- goto out_unlock;
+ goto out_unmark;
sched_exec();
goto out;
/* execve succeeded */
- mutex_unlock(¤t->cred_exec_mutex);
+ current->fs->in_exec = 0;
+ current->in_execve = 0;
acct_update_integrals(current);
free_bprm(bprm);
if (displaced)
fput(bprm->file);
}
-out_unlock:
- mutex_unlock(¤t->cred_exec_mutex);
+out_unmark:
+ if (clear_in_exec)
+ current->fs->in_exec = 0;
+ current->in_execve = 0;
out_free:
free_bprm(bprm);
return (ret >= 2) ? 2 : ret;
}
-int do_coredump(long signr, int exit_code, struct pt_regs * regs)
+void do_coredump(long signr, int exit_code, struct pt_regs *regs)
{
struct core_state core_state;
char corename[CORENAME_MAX_SIZE + 1];
put_cred(cred);
coredump_finish(mm);
fail:
- return retval;
+ return;
}