linux-kernel - [RFC PATCH 1/2] xfs: free the item in xfs_mru_cache

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250430084117.9850-2-hans.holmberg@wdc.com>
Date: Wed, 30 Apr 2025 08:41:21 +0000
From: Hans Holmberg <Hans.Holmberg@....com>
To: "linux-xfs@...r.kernel.org" <linux-xfs@...r.kernel.org>
CC: Carlos Maiolino <cem@...nel.org>, Dave Chinner <david@...morbit.com>,
	"Darrick J . Wong" <djwong@...nel.org>, hch <hch@....de>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, Hans Holmberg
	<Hans.Holmberg@....com>
Subject: [RFC PATCH 1/2] xfs: free the item in xfs_mru_cache_insert on failure

From: Christoph Hellwig <hch@....de>

Call the provided free_func when xfs_mru_cache_insert as that's what
the callers need to do anyway.

Signed-off-by: Christoph Hellwig <hch@....de>
Signed-off-by: Hans Holmberg <hans.holmberg@....com>
---
 fs/xfs/xfs_filestream.c | 15 ++++-----------
 fs/xfs/xfs_mru_cache.c  | 15 ++++++++++++---
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c
index a961aa420c48..044918fbae06 100644
--- a/fs/xfs/xfs_filestream.c
+++ b/fs/xfs/xfs_filestream.c
@@ -304,11 +304,9 @@ xfs_filestream_create_association(
 	 * for us, so all we need to do here is take another active reference to
 	 * the perag for the cached association.
 	 *
-	 * If we fail to store the association, we need to drop the fstrms
-	 * counter as well as drop the perag reference we take here for the
-	 * item. We do not need to return an error for this failure - as long as
-	 * we return a referenced AG, the allocation can still go ahead just
-	 * fine.
+	 * If we fail to store the association, we do not need to return an
+	 * error for this failure - as long as we return a referenced AG, the
+	 * allocation can still go ahead just fine.
 	 */
 	item = kmalloc(sizeof(*item), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
 	if (!item)
@@ -316,14 +314,9 @@ xfs_filestream_create_association(
 
 	atomic_inc(&pag_group(args->pag)->xg_active_ref);
 	item->pag = args->pag;
-	error = xfs_mru_cache_insert(mp->m_filestream, pino, &item->mru);
-	if (error)
-		goto out_free_item;
+	xfs_mru_cache_insert(mp->m_filestream, pino, &item->mru);
 	return 0;
 
-out_free_item:
-	xfs_perag_rele(item->pag);
-	kfree(item);
 out_put_fstrms:
 	atomic_dec(&args->pag->pagf_fstrms);
 	return 0;
diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c
index d0f5b403bdbe..08443ceec329 100644
--- a/fs/xfs/xfs_mru_cache.c
+++ b/fs/xfs/xfs_mru_cache.c
@@ -414,6 +414,8 @@ xfs_mru_cache_destroy(
  * To insert an element, call xfs_mru_cache_insert() with the data store, the
  * element's key and the client data pointer.  This function returns 0 on
  * success or ENOMEM if memory for the data element couldn't be allocated.
+ *
+ * The passed in elem is freed through the per-cache free_func on failure.
  */
 int
 xfs_mru_cache_insert(
@@ -421,14 +423,15 @@ xfs_mru_cache_insert(
 	unsigned long		key,
 	struct xfs_mru_cache_elem *elem)
 {
-	int			error;
+	int			error = -EINVAL;
 
 	ASSERT(mru && mru->lists);
 	if (!mru || !mru->lists)
-		return -EINVAL;
+		goto out_free;
 
+	error = -ENOMEM;
 	if (radix_tree_preload(GFP_KERNEL))
-		return -ENOMEM;
+		goto out_free;
 
 	INIT_LIST_HEAD(&elem->list_node);
 	elem->key = key;
@@ -440,6 +443,12 @@ xfs_mru_cache_insert(
 		_xfs_mru_cache_list_insert(mru, elem);
 	spin_unlock(&mru->lock);
 
+	if (error)
+		goto out_free;
+	return 0;
+
+out_free:
+	mru->free_func(mru->data, elem);
 	return error;
 }
 
-- 
2.34.1