Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754746Ab2FYRpt (ORCPT ); Mon, 25 Jun 2012 13:45:49 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:50310 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753974Ab2FYRpr (ORCPT ); Mon, 25 Jun 2012 13:45:47 -0400 From: Miklos Szeredi To: eparis@redhat.com Cc: viro@ZenIV.linux.org.uk, linux-kernel@vger.kernel.org, mszeredi@suse.cz Subject: [PATCH 3/3] audit: clean up refcounting in audit-tree Date: Mon, 25 Jun 2012 19:46:18 +0200 Message-Id: <1340646378-5169-4-git-send-email-miklos@szeredi.hu> X-Mailer: git-send-email 1.7.7 In-Reply-To: <1340646378-5169-1-git-send-email-miklos@szeredi.hu> References: <1340646378-5169-1-git-send-email-miklos@szeredi.hu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2724 Lines: 79 From: Miklos Szeredi Drop the initial reference by fsnotify_init_mark early instead of audit_tree_freeing_mark() at destroy time. In the cases we destroy the mark before we drop the initial reference we need to get rid of the get_mark that balances the put_mark in audit_tree_freeing_mark(). Signed-off-by: Miklos Szeredi --- kernel/audit_tree.c | 12 +++++++++--- 1 files changed, 9 insertions(+), 3 deletions(-) diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 31fdc48..7b95706 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -292,6 +292,7 @@ static void untag_chunk(struct node *p) spin_unlock(&hash_lock); spin_unlock(&entry->lock); fsnotify_destroy_mark(entry); + fsnotify_put_mark(&new->mark); /* drop initial reference */ goto out; Fallback: @@ -330,7 +331,6 @@ static int create_chunk(struct inode *inode, struct audit_tree *tree) spin_unlock(&hash_lock); chunk->dead = 1; spin_unlock(&entry->lock); - fsnotify_get_mark(entry); fsnotify_destroy_mark(entry); fsnotify_put_mark(entry); return 0; @@ -346,6 +346,7 @@ static int create_chunk(struct inode *inode, struct audit_tree *tree) insert_hash(chunk); spin_unlock(&hash_lock); spin_unlock(&entry->lock); + fsnotify_put_mark(entry); /* drop initial reference */ return 0; } @@ -411,7 +412,6 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) spin_unlock(&chunk_entry->lock); spin_unlock(&old_entry->lock); - fsnotify_get_mark(chunk_entry); fsnotify_destroy_mark(chunk_entry); fsnotify_put_mark(chunk_entry); @@ -444,6 +444,7 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) spin_unlock(&chunk_entry->lock); spin_unlock(&old_entry->lock); fsnotify_destroy_mark(old_entry); + fsnotify_put_mark(chunk_entry); /* drop initial reference */ fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ return 0; } @@ -915,7 +916,12 @@ static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark); evict_chunk(chunk); - fsnotify_put_mark(entry); + + /* + * We are guaranteed to have at least one reference to the mark from + * either the inode or the caller of fsnotify_destroy_mark(). + */ + BUG_ON(atomic_read(&entry->refcnt) < 1); } static bool audit_tree_send_event(struct fsnotify_group *group, struct inode *inode, -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/