[PATCH 3.13 140/212] target: fix memory leak on XCOPY
From: Kamal Mostafa <hidden>
Date: 2014-06-17 21:54:16
Also in:
lkml
Subsystem:
scsi target subsystem, the rest · Maintainers:
"Martin K. Petersen", Linus Torvalds
3.13.11.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka <mpatocka@redhat.com> commit 1e1110c43b1cda9fe77fc4a04835e460550e6b3c upstream. On each processed XCOPY command, two "kmalloc-512" memory objects are leaked. These represent two allocations of struct xcopy_pt_cmd in target_core_xcopy.c. The reason for the memory leak is that the cmd_kref field is not initialized (thus, it is zero because the allocations were done with kzalloc). When we decrement zero kref in target_put_sess_cmd, the result is not zero, thus target_release_cmd_kref is not called. This patch fixes the bug by moving kref initialization from target_get_sess_cmd to transport_init_se_cmd (this function is called from target_core_xcopy.c, so it will correctly initialize cmd_kref). It can be easily verified that all code that calls target_get_sess_cmd also calls transport_init_se_cmd earlier, thus moving kref_init shouldn't introduce any new problems. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Nicholas Bellinger <redacted> Signed-off-by: Kamal Mostafa <redacted> --- drivers/target/target_core_transport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index dee2be1..3ef25bd 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c@@ -1079,6 +1079,7 @@ void transport_init_se_cmd( init_completion(&cmd->cmd_wait_comp); init_completion(&cmd->task_stop_comp); spin_lock_init(&cmd->t_state_lock); + kref_init(&cmd->cmd_kref); cmd->transport_state = CMD_T_DEV_ACTIVE; cmd->se_tfo = tfo;
@@ -2254,7 +2255,6 @@ int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd, unsigned long flags; int ret = 0; - kref_init(&se_cmd->cmd_kref); /* * Add a second kref if the fabric caller is expecting to handle * fabric acknowledgement that requires two target_put_sess_cmd()
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1.9.1