Subject: CVE-2024-26931: scsi: qla2xxx: Fix command flush on cable pull

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

scsi: qla2xxx: Fix command flush on cable pull

System crash due to command failed to flush back to SCSI layer.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP NOPTI
 CPU: 27 PID: 793455 Comm: kworker/u130:6 Kdump: loaded Tainted: G           OE    --------- -  - 4.18.0-372.9.1.el8.x86_64 #1
 Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 09/03/2021
 Workqueue: nvme-wq nvme_fc_connect_ctrl_work [nvme_fc]
 RIP: 0010:__wake_up_common+0x4c/0x190
 Code: 24 10 4d 85 c9 74 0a 41 f6 01 04 0f 85 9d 00 00 00 48 8b 43 08 48 83 c3 08 4c 8d 48 e8 49 8d 41 18 48 39 c3 0f 84 f0 00 00 00 <49> 8b 41 18 89 54 24 08 31 ed 4c 8d 70 e8 45 8b 29 41 f6 c5 04 75
 RSP: 0018:ffff95f3e0cb7cd0 EFLAGS: 00010086
 RAX: 0000000000000000 RBX: ffff8b08d3b26328 RCX: 0000000000000000
 RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8b08d3b26320
 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffffffffe8
 R10: 0000000000000000 R11: ffff95f3e0cb7a60 R12: ffff95f3e0cb7d20
 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff8b2fdf6c0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 0000002f1e410002 CR4: 00000000007706e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  __wake_up_common_lock+0x7c/0xc0
  qla_nvme_ls_req+0x355/0x4c0 [qla2xxx]
 qla2xxx [0000:12:00.1]-f084:3: qlt_free_session_done: se_sess 0000000000000000 / sess ffff8ae1407ca000 from port 21:32:00:02:ac:07:ee:b8 loop_id 0x02 s_id 01:02:00 logout 1 keep 0 els_logo 0
 ? __nvme_fc_send_ls_req+0x260/0x380 [nvme_fc]
 qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:00:02:ac:07:ee:b8 state transitioned from ONLINE to LOST - portid=010200.
  ? nvme_fc_send_ls_req.constprop.42+0x1a/0x45 [nvme_fc]
 qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320002ac07eeb8. rport ffff8ae598122000 roles 1
 ? nvme_fc_connect_ctrl_work.cold.63+0x1e3/0xa7d [nvme_fc]
 qla2xxx [0000:12:00.1]-f084:3: qlt_free_session_done: se_sess 0000000000000000 / sess ffff8ae14801e000 from port 21:32:01:02:ad:f7:ee:b8 loop_id 0x04 s_id 01:02:01 logout 1 keep 0 els_logo 0
  ? __switch_to+0x10c/0x450
 ? process_one_work+0x1a7/0x360
 qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:01:02:ad:f7:ee:b8 state transitioned from ONLINE to LOST - portid=010201.
  ? worker_thread+0x1ce/0x390
  ? create_worker+0x1a0/0x1a0
 qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320102adf7eeb8. rport ffff8ae3b2312800 roles 70
  ? kthread+0x10a/0x120
 qla2xxx [0000:12:00.1]-2112:3: qla_nvme_unregister_remote_port: unregister remoteport on ffff8ae14801e000 21320102adf7eeb8
  ? set_kthread_struct+0x40/0x40
 qla2xxx [0000:12:00.1]-2110:3: remoteport_delete of ffff8ae14801e000 21320102adf7eeb8 completed.
  ? ret_from_fork+0x1f/0x40
 qla2xxx [0000:12:00.1]-f086:3: qlt_free_session_done: waiting for sess ffff8ae14801e000 logout

The system was under memory stress where driver was not able to allocate an
SRB to carry out error recovery of cable pull.  The failure to flush causes
upper layer to start modifying scsi_cmnd.  When the system frees up some
memory, the subsequent cable pull trigger another command flush. At this
point the driver access a null pointer when attempting to DMA unmap the
SGL.

Add a check to make sure commands are flush back on session tear down to
prevent the null pointer access.

The Linux kernel CVE team has assigned CVE-2024-26931 to this issue.

Affected and fixed versions
===========================

	Fixed in 4.19.312 with commit b73377124f56
	Fixed in 5.4.274 with commit d7a68eee87b0
	Fixed in 5.10.215 with commit 67b2d35853c2
	Fixed in 5.15.154 with commit a859f6a8f423
	Fixed in 6.1.84 with commit 09c0ac18cac2
	Fixed in 6.6.24 with commit 8de1584ec4fe
	Fixed in 6.7.12 with commit 8f0d32004e3a
	Fixed in 6.8.3 with commit ec7587eef003
	Fixed in 6.9 with commit a27d4d0e7de3

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-26931
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/scsi/qla2xxx/qla_target.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/b73377124f56d2fec154737c2f8d2e839c237d5a
	https://git.kernel.org/stable/c/d7a68eee87b05d4e29419e6f151aef99314970a9
	https://git.kernel.org/stable/c/67b2d35853c2da25a8ca1c4190a5e96d3083c2ac
	https://git.kernel.org/stable/c/a859f6a8f4234b8ef62862bf7a92f1af5f8cd47a
	https://git.kernel.org/stable/c/09c0ac18cac206ed1218b1fe6c1a0918e5ea9211
	https://git.kernel.org/stable/c/8de1584ec4fe0ebea33c273036e7e0a05e65c81d
	https://git.kernel.org/stable/c/8f0d32004e3a572bb77e6c11c2797c87f8c9703d
	https://git.kernel.org/stable/c/ec7587eef003cab15a13446d67c3adb88146a150
	https://git.kernel.org/stable/c/a27d4d0e7de305def8a5098a614053be208d1aa1