ocfs2: fix dead lock risk when kmalloc failed in dlm_query_region_handler
PATCH v2 1/1 ocfs2: fix dead lock risk when kmalloc failed in dlm_query_region_handler
From: Zhonghua Guo <[email protected]>
In dlm_query_region_handler(), once kmalloc failed, it will unlock dlm_domain_lock without lock first, then dead lock happens.
Signed-off-by Zhonghua Guo <[email protected]>
Signed-off-by Joseph Qi <[email protected]>
Reviewed-by Srinivas Eeda <[email protected]>
Reviewed-by Andrew Morton <[email protected]>
Tested-by Joseph Qi <[email protected]>
--- fs/ocfs2/dlm/dlmdomain.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-)
fs/ocfs2/dlm/dlmdomain.c +9 -12
@@ -1123,7 +1123,6 @@ static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,struct dlm_ctxt *dlm =NULL ;char *local =NULL ;int status =0 ; -int locked =0 ; qr = (struct dlm_query_region *) msg->buf;
@@ -1132,10 +1131,8 @@ static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,/* buffer used in dlm_mast_regions() */ local =kmalloc (sizeof (qr->qr_regions),GFP_KERNEL ); -if (!local) { - status = -ENOMEM ; - goto bail; - } +if (!local) +return -ENOMEM ; status = -EINVAL ;
@@ -1144,16 +1141,15 @@ static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,if (!dlm) {mlog (ML_ERROR ,"Node %d queried hb regions on domain %s " "before join domain\n" , qr->qr_node, qr->qr_domain); - goto bail; + goto out_domain_lock; }spin_lock (&dlm->spinlock); - locked =1 ;if (dlm->joining_node != qr->qr_node) {mlog (ML_ERROR ,"Node %d queried hb regions on domain %s " "but joining node is %d\n" , qr->qr_node, qr->qr_domain, dlm->joining_node); - goto bail; + goto out_dlm_lock; }/* Support for global heartbeat was added in 1.1 */
@@ -1163,14 +1159,15 @@ static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,"but active dlm protocol is %d.%d\n" , qr->qr_node, qr->qr_domain, dlm->dlm_locking_proto.pv_major, dlm->dlm_locking_proto.pv_minor); - goto bail; + goto out_dlm_lock; } status =dlm_match_regions (dlm, qr, local,sizeof (qr->qr_regions)); -bail: -if (locked) -spin_unlock (&dlm->spinlock); +out_dlm_lock: +spin_unlock (&dlm->spinlock); + +out_domain_lock:spin_unlock (&dlm_domain_lock);kfree (local);
Signature · 1 line
1.8.4.3