Merge branch 'master' into next

[safe/jmp/linux-2.6] / fs / exec.c

diff --git a/fs/exec.c b/fs/exec.c
index 9881dc3..b9f1c14 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1056,16 +1056,32 @@ EXPORT_SYMBOL(install_exec_creds);
  * - the caller must hold current->cred_exec_mutex to protect against
  *   PTRACE_ATTACH
  */
-void check_unsafe_exec(struct linux_binprm *bprm)
+void check_unsafe_exec(struct linux_binprm *bprm, struct files_struct *files)
 {
-       struct task_struct *p = current;
+       struct task_struct *p = current, *t;
+       unsigned long flags;
+       unsigned n_fs, n_files, n_sighand;
 
        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;
+       n_files = 1;
+       n_sighand = 1;
+       lock_task_sighand(p, &flags);
+       for (t = next_thread(p); t != p; t = next_thread(t)) {
+               if (t->fs == p->fs)
+                       n_fs++;
+               if (t->files == files)
+                       n_files++;
+               n_sighand++;
+       }
+
+       if (atomic_read(&p->fs->count) > n_fs ||
+           atomic_read(&p->files->count) > n_files ||
+           atomic_read(&p->sighand->count) > n_sighand)
                bprm->unsafe |= LSM_UNSAFE_SHARE;
+
+       unlock_task_sighand(p, &flags);
 }
 
 /* 
@@ -1284,7 +1300,7 @@ int do_execve(char * filename,
        bprm->cred = prepare_exec_creds();
        if (!bprm->cred)
                goto out_unlock;
-       check_unsafe_exec(bprm);
+       check_unsafe_exec(bprm, displaced);
 
        file = open_exec(filename);
        retval = PTR_ERR(file);