Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[sfrench/cifs-2.6.git] / fs / binfmt_misc.c

diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
index ce7181ea60fa9af516e2a8774fd1fc2fac38274a..a7c5a9861bef5a73b8f7377dfa9e045427b915c7 100644 (file)
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -54,7 +54,7 @@ typedef struct {
        int size;                       /* size of magic/mask */
        char *magic;                    /* magic or filename extension */
        char *mask;                     /* mask, NULL for exact match */
-       char *interpreter;              /* filename of interpreter */
+       const char *interpreter;        /* filename of interpreter */
        char *name;
        struct dentry *dentry;
        struct file *interp_file;
@@ -131,27 +131,26 @@ static int load_misc_binary(struct linux_binprm *bprm)
 {
        Node *fmt;
        struct file *interp_file = NULL;
-       char iname[BINPRM_BUF_SIZE];
-       const char *iname_addr = iname;
        int retval;
        int fd_binary = -1;
 
        retval = -ENOEXEC;
        if (!enabled)
-               goto ret;
+               return retval;
 
        /* to keep locking time low, we copy the interpreter string */
        read_lock(&entries_lock);
        fmt = check_file(bprm);
        if (fmt)
-               strlcpy(iname, fmt->interpreter, BINPRM_BUF_SIZE);
+               dget(fmt->dentry);
        read_unlock(&entries_lock);
        if (!fmt)
-               goto ret;
+               return retval;
 
        /* Need to be able to load the file after exec */
+       retval = -ENOENT;
        if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)
-               return -ENOENT;
+               goto ret;
 
        if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
                retval = remove_arg_zero(bprm);
@@ -195,22 +194,22 @@ static int load_misc_binary(struct linux_binprm *bprm)
        bprm->argc++;
 
        /* add the interp as argv[0] */
-       retval = copy_strings_kernel(1, &iname_addr, bprm);
+       retval = copy_strings_kernel(1, &fmt->interpreter, bprm);
        if (retval < 0)
                goto error;
        bprm->argc++;
 
        /* Update interp in case binfmt_script needs it. */
-       retval = bprm_change_interp(iname, bprm);
+       retval = bprm_change_interp(fmt->interpreter, bprm);
        if (retval < 0)
                goto error;
 
-       if (fmt->flags & MISC_FMT_OPEN_FILE && fmt->interp_file) {
+       if (fmt->flags & MISC_FMT_OPEN_FILE) {
                interp_file = filp_clone_open(fmt->interp_file);
                if (!IS_ERR(interp_file))
                        deny_write_access(interp_file);
        } else {
-               interp_file = open_exec(iname);
+               interp_file = open_exec(fmt->interpreter);
        }
        retval = PTR_ERR(interp_file);
        if (IS_ERR(interp_file))
@@ -238,6 +237,7 @@ static int load_misc_binary(struct linux_binprm *bprm)
                goto error;
 
 ret:
+       dput(fmt->dentry);
        return retval;
 error:
        if (fd_binary > 0)
@@ -594,8 +594,13 @@ static struct inode *bm_get_inode(struct super_block *sb, int mode)
 
 static void bm_evict_inode(struct inode *inode)
 {
+       Node *e = inode->i_private;
+
+       if (e && e->flags & MISC_FMT_OPEN_FILE)
+               filp_close(e->interp_file, NULL);
+
        clear_inode(inode);
-       kfree(inode->i_private);
+       kfree(e);
 }
 
 static void kill_node(Node *e)
@@ -603,24 +608,14 @@ static void kill_node(Node *e)
        struct dentry *dentry;
 
        write_lock(&entries_lock);
-       dentry = e->dentry;
-       if (dentry) {
-               list_del_init(&e->list);
-               e->dentry = NULL;
-       }
+       list_del_init(&e->list);
        write_unlock(&entries_lock);
 
-       if ((e->flags & MISC_FMT_OPEN_FILE) && e->interp_file) {
-               filp_close(e->interp_file, NULL);
-               e->interp_file = NULL;
-       }
-
-       if (dentry) {
-               drop_nlink(d_inode(dentry));
-               d_drop(dentry);
-               dput(dentry);
-               simple_release_fs(&bm_mnt, &entry_count);
-       }
+       dentry = e->dentry;
+       drop_nlink(d_inode(dentry));
+       d_drop(dentry);
+       dput(dentry);
+       simple_release_fs(&bm_mnt, &entry_count);
 }
 
 /* /<entry> */
@@ -665,7 +660,8 @@ static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
                root = file_inode(file)->i_sb->s_root;
                inode_lock(d_inode(root));
 
-               kill_node(e);
+               if (!list_empty(&e->list))
+                       kill_node(e);
 
                inode_unlock(d_inode(root));
                break;
@@ -794,7 +790,7 @@ static ssize_t bm_status_write(struct file *file, const char __user *buffer,
                inode_lock(d_inode(root));
 
                while (!list_empty(&entries))
-                       kill_node(list_entry(entries.next, Node, list));
+                       kill_node(list_first_entry(&entries, Node, list));
 
                inode_unlock(d_inode(root));
                break;