cifs: close sget() races

have ->s_fs_info set by the set() callback passed to sget()

Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2011-06-17 09:47:23 -04:00
parent d757d71bfc
commit ee01a14d9d

View File

@ -629,6 +629,13 @@ out:
return dparent;
}
static int cifs_set_super(struct super_block *sb, void *data)
{
struct cifs_mnt_data *mnt_data = data;
sb->s_fs_info = mnt_data->cifs_sb;
return set_anon_super(sb, NULL);
}
static struct dentry *
cifs_do_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
@ -678,14 +685,14 @@ cifs_do_mount(struct file_system_type *fs_type,
mnt_data.cifs_sb = cifs_sb;
mnt_data.flags = flags;
sb = sget(fs_type, cifs_match_super, set_anon_super, &mnt_data);
sb = sget(fs_type, cifs_match_super, cifs_set_super, &mnt_data);
if (IS_ERR(sb)) {
root = ERR_CAST(sb);
cifs_umount(cifs_sb);
goto out;
}
if (sb->s_fs_info) {
if (sb->s_root) {
cFYI(1, "Use existing superblock");
cifs_umount(cifs_sb);
goto out_shared;
@ -694,7 +701,6 @@ cifs_do_mount(struct file_system_type *fs_type,
sb->s_flags = flags;
/* BB should we make this contingent on mount parm? */
sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
sb->s_fs_info = cifs_sb;
rc = cifs_read_super(sb);
if (rc) {