[PATCH net-next v5 13/16] ocfs2: Fix use of slab data with sendpage
From: David Howells <dhowells@redhat.com>
Date: 2023-06-23 22:58:05
Also in:
linux-mm, lkml, ocfs2-devel
Subsystem:
filesystems (vfs and infrastructure), oracle cluster filesystem 2 (ocfs2), the rest · Maintainers:
Alexander Viro, Christian Brauner, Mark Fasheh, Joel Becker, Joseph Qi, Linus Torvalds
ocfs2 uses kzalloc() to allocate buffers for o2net_hand, o2net_keep_req and
o2net_keep_resp and then passes these to sendpage. This isn't really
allowed as the lifetime of slab objects is not controlled by page ref -
though in this case it will probably work. sendmsg() with MSG_SPLICE_PAGES
will, however, print a warning and give an error.
Fix it to use folio_alloc() instead to allocate a buffer for the handshake
message, keepalive request and reply messages.
Fixes: 98211489d414 ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Mark Fasheh <mark@fasheh.com>
cc: Kurt Hackel <redacted>
cc: Joel Becker <jlbec@evilplan.org>
cc: Joseph Qi <joseph.qi@linux.alibaba.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: ocfs2-devel@oss.oracle.com
cc: netdev@vger.kernel.org
---
fs/ocfs2/cluster/tcp.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index aecbd712a00c..929a1133bc18 100644
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c@@ -2087,18 +2087,24 @@ void o2net_stop_listening(struct o2nm_node *node) int o2net_init(void) { + struct folio *folio; + void *p; unsigned long i; o2quo_init(); - o2net_debugfs_init(); - o2net_hand = kzalloc(sizeof(struct o2net_handshake), GFP_KERNEL); - o2net_keep_req = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL); - o2net_keep_resp = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL); - if (!o2net_hand || !o2net_keep_req || !o2net_keep_resp) + folio = folio_alloc(GFP_KERNEL | __GFP_ZERO, 0); + if (!folio) goto out; + p = folio_address(folio); + o2net_hand = p; + p += sizeof(struct o2net_handshake); + o2net_keep_req = p; + p += sizeof(struct o2net_msg); + o2net_keep_resp = p; + o2net_hand->protocol_version = cpu_to_be64(O2NET_PROTOCOL_VERSION); o2net_hand->connector_id = cpu_to_be64(1);
@@ -2124,9 +2130,6 @@ int o2net_init(void) return 0; out: - kfree(o2net_hand); - kfree(o2net_keep_req); - kfree(o2net_keep_resp); o2net_debugfs_exit(); o2quo_exit(); return -ENOMEM;
@@ -2135,8 +2138,6 @@ int o2net_init(void) void o2net_exit(void) { o2quo_exit(); - kfree(o2net_hand); - kfree(o2net_keep_req); - kfree(o2net_keep_resp); o2net_debugfs_exit(); + folio_put(virt_to_folio(o2net_hand)); }