From: Manish Rangankar <manish.rangankar@xxxxxxxxxx> [ Upstream commit d5632b11f0a17efa6356311e535ae135d178438d ] The kernel panic was observed after switch side perturbation, BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8132b5a0>] strcmp+0x20/0x40 PGD 0 Oops: 0000 [#1] SMP CPU: 8 PID: 647 Comm: kworker/8:1 Tainted: G W OE ------------ 3.10.0-693.el7.x86_64 #1 Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 06/20/2018 Workqueue: slowpath-13:00. qed_slowpath_task [qed] task: ffff880429eb8fd0 ti: ffff880429190000 task.ti: ffff880429190000 RIP: 0010:[<ffffffff8132b5a0>] [<ffffffff8132b5a0>] strcmp+0x20/0x40 RSP: 0018:ffff880429193c68 EFLAGS: 00010202 RAX: 000000000000000a RBX: 0000000000000002 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff88042bda7a41 RBP: ffff880429193c68 R08: 000000000000ffff R09: 000000000000ffff R10: 0000000000000007 R11: ffff88042b3af338 R12: ffff880420b007a0 R13: ffff88081aa56af8 R14: 0000000000000001 R15: ffff88081aa50410 FS: 0000000000000000(0000) GS:ffff88042fe00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000019f2000 CR4: 00000000003407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffff880429193d20 ffffffffc02a0c90 ffffc90004b32000 ffff8803fd3ec600 ffff88042bda7800 ffff88042bda7a00 ffff88042bda7840 ffff88042bda7a40 0000000129193d10 2e3836312e323931 ff000a342e363232 ffffffffc01ad99d Call Trace: [<ffffffffc02a0c90>] qedi_get_protocol_tlv_data+0x270/0x470 [qedi] [<ffffffffc01ad99d>] ? qed_mfw_process_tlv_req+0x24d/0xbf0 [qed] [<ffffffffc01653ae>] qed_mfw_fill_tlv_data+0x5e/0xd0 [qed] [<ffffffffc01ad9b9>] qed_mfw_process_tlv_req+0x269/0xbf0 [qed] Fix kernel NULL pointer deref by checking for session is online before getting iSCSI TLV data. Signed-off-by: Manish Rangankar <manish.rangankar@xxxxxxxxxx> Reviewed-by: Lee Duncan <lduncan@xxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/scsi/qedi/qedi_main.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/scsi/qedi/qedi_main.c b/drivers/scsi/qedi/qedi_main.c index e5bd035ebad0..4de740da547b 100644 --- a/drivers/scsi/qedi/qedi_main.c +++ b/drivers/scsi/qedi/qedi_main.c @@ -952,6 +952,9 @@ static int qedi_find_boot_info(struct qedi_ctx *qedi, cls_sess = iscsi_conn_to_session(cls_conn); sess = cls_sess->dd_data; + if (!iscsi_is_session_online(cls_sess)) + continue; + if (pri_ctrl_flags) { if (!strcmp(pri_tgt->iscsi_name, sess->targetname) && !strcmp(pri_tgt->ip_addr, ep_ip_addr)) { -- 2.19.1