From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Mon, 01 Feb 2021 12:25:43 +0000 Subject: [PATCH] ocfs2: Fix a use after free on error Message-Id: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Mark Fasheh , Jiri Slaby Cc: Joel Becker , Joseph Qi , Andrew Morton , Alex Shi , Jens Axboe , ocfs2-devel@oss.oracle.com, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org The error handling in this function frees "reg" but it is still on the "o2hb_all_regions" list so it will lead to a use after free. The fix for this is to only add it to the list after everything has succeeded. Fixes: 1cf257f51191 ("ocfs2: fix memory leak") Signed-off-by: Dan Carpenter --- This is from static analysis and hasn't been tested. fs/ocfs2/cluster/heartbeat.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c index 0179a73a3fa2..92af4dc813e7 100644 --- a/fs/ocfs2/cluster/heartbeat.c +++ b/fs/ocfs2/cluster/heartbeat.c @@ -2025,7 +2025,6 @@ static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *g } set_bit(reg->hr_region_num, o2hb_region_bitmap); } - list_add_tail(®->hr_all_item, &o2hb_all_regions); spin_unlock(&o2hb_live_lock); config_item_init_type_name(®->hr_item, name, &o2hb_region_type); @@ -2053,6 +2052,10 @@ static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *g o2hb_debug_region_init(reg, o2hb_debug_dir); + spin_lock(&o2hb_live_lock); + list_add_tail(®->hr_all_item, &o2hb_all_regions); + spin_unlock(&o2hb_live_lock); + return ®->hr_item; unregister_handler: -- 2.29.2