This is a note to let you know that I've just added the patch titled
scsi: target: iscsit: Free cmds before session free
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-target-iscsit-free-cmds-before-session-free.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9d6b0ddc52f63d6ed5fdab7a84bff31df35aa42a
Author: Dmitry Bogdanov <d.bogdanov@xxxxxxxxx>
Date: Sat Mar 18 20:56:17 2023 -0500
scsi: target: iscsit: Free cmds before session free
[ Upstream commit d8990b5a4d065f38f35d69bcd627ec5a7f8330ca ]
Commands from recovery entries are freed after session has been closed.
That leads to use-after-free at command free or NPE with such call trace:
Time2Retain timer expired for SID: 1, cleaning up iSCSI session.
BUG: kernel NULL pointer dereference, address: 0000000000000140
RIP: 0010:sbitmap_queue_clear+0x3a/0xa0
Call Trace:
target_release_cmd_kref+0xd1/0x1f0 [target_core_mod]
transport_generic_free_cmd+0xd1/0x180 [target_core_mod]
iscsit_free_cmd+0x53/0xd0 [iscsi_target_mod]
iscsit_free_connection_recovery_entries+0x29d/0x320 [iscsi_target_mod]
iscsit_close_session+0x13a/0x140 [iscsi_target_mod]
iscsit_check_post_dataout+0x440/0x440 [iscsi_target_mod]
call_timer_fn+0x24/0x140
Move cleanup of recovery enrties to before session freeing.
Reported-by: Forza <forza@xxxxxxxxxxxx>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@xxxxxxxxx>
Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230319015620.96006-7-michael.christie@xxxxxxxxxx
Reviewed-by: Maurizio Lombardi <mlombard@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 6bb8403580729..075e2a6fb474f 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -4385,6 +4385,9 @@ int iscsit_close_session(struct iscsi_session *sess)
iscsit_stop_time2retain_timer(sess);
spin_unlock_bh(&se_tpg->session_lock);
+ if (sess->sess_ops->ErrorRecoveryLevel == 2)
+ iscsit_free_connection_recovery_entries(sess);
+
/*
* transport_deregister_session_configfs() will clear the
* struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
@@ -4412,9 +4415,6 @@ int iscsit_close_session(struct iscsi_session *sess)
transport_deregister_session(sess->se_sess);
- if (sess->sess_ops->ErrorRecoveryLevel == 2)
- iscsit_free_connection_recovery_entries(sess);
-
iscsit_free_all_ooo_cmdsns(sess);
spin_lock_bh(&se_tpg->session_lock);
