Linux 6.9-rc1

[linux-2.6-microblaze.git] / fs / exec.c

diff --git a/fs/exec.c b/fs/exec.c
index 8cdd5b2..ff6f266 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -128,7 +128,7 @@ SYSCALL_DEFINE1(uselib, const char __user *, library)
        struct filename *tmp = getname(library);
        int error = PTR_ERR(tmp);
        static const struct open_flags uselib_flags = {
-               .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
+               .open_flag = O_LARGEFILE | O_RDONLY,
                .acc_mode = MAY_READ | MAY_EXEC,
                .intent = LOOKUP_OPEN,
                .lookup_flags = LOOKUP_FOLLOW,
@@ -904,6 +904,10 @@ EXPORT_SYMBOL(transfer_args_to_stack);
 
 #endif /* CONFIG_MMU */
 
+/*
+ * On success, caller must call do_close_execat() on the returned
+ * struct file to close it.
+ */
 static struct file *do_open_execat(int fd, struct filename *name, int flags)
 {
        struct file *file;
@@ -948,6 +952,17 @@ exit:
        return ERR_PTR(err);
 }
 
+/**
+ * open_exec - Open a path name for execution
+ *
+ * @name: path name to open with the intent of executing it.
+ *
+ * Returns ERR_PTR on failure or allocated struct file on success.
+ *
+ * As this is a wrapper for the internal do_open_execat(), callers
+ * must call allow_write_access() before fput() on release. Also see
+ * do_close_execat().
+ */
 struct file *open_exec(const char *name)
 {
        struct filename *filename = getname_kernel(name);
@@ -1143,7 +1158,6 @@ static int de_thread(struct task_struct *tsk)
 
                BUG_ON(leader->exit_state != EXIT_ZOMBIE);
                leader->exit_state = EXIT_DEAD;
-
                /*
                 * We are going to release_task()->ptrace_unlink() silently,
                 * the tracer can sleep in do_wait(). EXIT_DEAD guarantees
@@ -1409,6 +1423,9 @@ int begin_new_exec(struct linux_binprm * bprm)
 
 out_unlock:
        up_write(&me->signal->exec_update_lock);
+       if (!bprm->cred)
+               mutex_unlock(&me->signal->cred_guard_mutex);
+
 out:
        return retval;
 }
@@ -1484,6 +1501,15 @@ static int prepare_bprm_creds(struct linux_binprm *bprm)
        return -ENOMEM;
 }
 
+/* Matches do_open_execat() */
+static void do_close_execat(struct file *file)
+{
+       if (!file)
+               return;
+       allow_write_access(file);
+       fput(file);
+}
+
 static void free_bprm(struct linux_binprm *bprm)
 {
        if (bprm->mm) {
@@ -1495,10 +1521,7 @@ static void free_bprm(struct linux_binprm *bprm)
                mutex_unlock(&current->signal->cred_guard_mutex);
                abort_creds(bprm->cred);
        }
-       if (bprm->file) {
-               allow_write_access(bprm->file);
-               fput(bprm->file);
-       }
+       do_close_execat(bprm->file);
        if (bprm->executable)
                fput(bprm->executable);
        /* If a binfmt changed the interp, free it. */
@@ -1520,8 +1543,7 @@ static struct linux_binprm *alloc_bprm(int fd, struct filename *filename, int fl
 
        bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
        if (!bprm) {
-               allow_write_access(file);
-               fput(file);
+               do_close_execat(file);
                return ERR_PTR(-ENOMEM);
        }
 
@@ -1610,6 +1632,7 @@ static void check_unsafe_exec(struct linux_binprm *bprm)
        }
        rcu_read_unlock();
 
+       /* "users" and "in_exec" locked for copy_fs() */
        if (p->fs->users > n_fs)
                bprm->unsafe |= LSM_UNSAFE_SHARE;
        else
@@ -1696,7 +1719,6 @@ static int prepare_binprm(struct linux_binprm *bprm)
  */
 int remove_arg_zero(struct linux_binprm *bprm)
 {
-       int ret = 0;
        unsigned long offset;
        char *kaddr;
        struct page *page;
@@ -1707,10 +1729,8 @@ int remove_arg_zero(struct linux_binprm *bprm)
        do {
                offset = bprm->p & ~PAGE_MASK;
                page = get_arg_page(bprm, bprm->p, 0);
-               if (!page) {
-                       ret = -EFAULT;
-                       goto out;
-               }
+               if (!page)
+                       return -EFAULT;
                kaddr = kmap_local_page(page);
 
                for (; offset < PAGE_SIZE && kaddr[offset];
@@ -1723,10 +1743,8 @@ int remove_arg_zero(struct linux_binprm *bprm)
 
        bprm->p++;
        bprm->argc--;
-       ret = 0;
 
-out:
-       return ret;
+       return 0;
 }
 EXPORT_SYMBOL(remove_arg_zero);
 
@@ -1826,9 +1844,6 @@ static int exec_binprm(struct linux_binprm *bprm)
        return 0;
 }
 
-/*
- * sys_execve() executes a new program.
- */
 static int bprm_execve(struct linux_binprm *bprm)
 {
        int retval;