From cc84bbdde901ef44df1e491db8073e567bcc1225 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 18 Mar 2023 20:56:16 -0500 Subject: [PATCH] scsi: target: iscsit: Stop/wait on cmds during conn close [ Upstream commit 395cee83d02de3073211b04fc85724f4abc663ad ] This fixes a bug added in commit f36199355c64 ("scsi: target: iscsi: Fix cmd abort fabric stop race"). If we have multiple sessions to the same se_device we can hit a race where a LUN_RESET on one session cleans up the se_cmds from under another session which is being closed. This results in the closing session freeing its conn/session structs while they are still in use. The bug is: 1. Session1 has IO se_cmd1. 2. Session2 can also have se_cmds for I/O and optionally TMRs for ABORTS but then gets a LUN_RESET. 3. The LUN_RESET on session2 sees the se_cmds on session1 and during the drain stages marks them all with CMD_T_ABORTED. 4. session1 is now closed so iscsit_release_commands_from_conn() only sees se_cmds with the CMD_T_ABORTED bit set and returns immediately even though we have outstanding commands. 5. session1's connection and session are freed. 6. The backend request for se_cmd1 completes and it accesses the freed connection/session. This hooks the iscsit layer into the cmd counter code, so we can wait for all outstanding se_cmds before freeing the connection. Fixes: f36199355c64 ("scsi: target: iscsi: Fix cmd abort fabric stop race") Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-6-michael.christie@oracle.com Reviewed-by: Maurizio Lombardi Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/target/iscsi/iscsi_target.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 11115c207844..83b007141229 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -4245,6 +4245,16 @@ static void iscsit_release_commands_from_conn(struct iscsit_conn *conn) iscsit_free_cmd(cmd, true); } + + /* + * Wait on commands that were cleaned up via the aborted_task path. + * LLDs that implement iscsit_wait_conn will already have waited for + * commands. + */ + if (!conn->conn_transport->iscsit_wait_conn) { + target_stop_cmd_counter(conn->cmd_cnt); + target_wait_for_cmds(conn->cmd_cnt); + } } static void iscsit_stop_timers_for_cmds(