Fix the race between capifs remount and node creation
we don't want to deal with half-updated config
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/drivers/isdn/capi/capifs.c b/drivers/isdn/capi/capifs.c
index 8f9f3b5..bff72d8 100644
--- a/drivers/isdn/capi/capifs.c
+++ b/drivers/isdn/capi/capifs.c
@@ -75,14 +75,17 @@
}
}
- replace_mount_options(s, new_opt);
+ mutex_lock(&s->s_root->d_inode->i_mutex);
+ replace_mount_options(s, new_opt);
config.setuid = setuid;
config.setgid = setgid;
config.uid = uid;
config.gid = gid;
config.mode = mode;
+ mutex_unlock(&s->s_root->d_inode->i_mutex);
+
return 0;
}
@@ -153,13 +156,16 @@
if (!inode)
return;
inode->i_ino = number+2;
+
+ dentry = get_node(number);
+
+ /* config contents is protected by root's i_mutex */
inode->i_uid = config.setuid ? config.uid : current_fsuid();
inode->i_gid = config.setgid ? config.gid : current_fsgid();
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
init_special_inode(inode, S_IFCHR|config.mode, device);
//inode->i_op = &capifs_file_inode_operations;
- dentry = get_node(number);
if (!IS_ERR(dentry) && !dentry->d_inode)
d_instantiate(dentry, inode);
mutex_unlock(&capifs_root->d_inode->i_mutex);