From: Mike Christie michael.christie@oracle.com
[ 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 michael.christie@oracle.com Link: https://lore.kernel.org/r/20230319015620.96006-6-michael.christie@oracle.com Reviewed-by: Maurizio Lombardi mlombard@redhat.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 11115c2078446..83b0071412294 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(