CVE-2024-26931

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> scsi: qla2xxx: Fix command flush on cable pull<br /> <br /> System crash due to command failed to flush back to SCSI layer.<br /> <br /> BUG: unable to handle kernel NULL pointer dereference at 0000000000000000<br /> PGD 0 P4D 0<br /> Oops: 0000 [#1] SMP NOPTI<br /> CPU: 27 PID: 793455 Comm: kworker/u130:6 Kdump: loaded Tainted: G OE --------- - - 4.18.0-372.9.1.el8.x86_64 #1<br /> Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 09/03/2021<br /> Workqueue: nvme-wq nvme_fc_connect_ctrl_work [nvme_fc]<br /> RIP: 0010:__wake_up_common+0x4c/0x190<br /> 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 8b 41 18 89 54 24 08 31 ed 4c 8d 70 e8 45 8b 29 41 f6 c5 04 75<br /> RSP: 0018:ffff95f3e0cb7cd0 EFLAGS: 00010086<br /> RAX: 0000000000000000 RBX: ffff8b08d3b26328 RCX: 0000000000000000<br /> RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8b08d3b26320<br /> RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffffffffe8<br /> R10: 0000000000000000 R11: ffff95f3e0cb7a60 R12: ffff95f3e0cb7d20<br /> R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000<br /> FS: 0000000000000000(0000) GS:ffff8b2fdf6c0000(0000) knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 0000000000000000 CR3: 0000002f1e410002 CR4: 00000000007706e0<br /> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> PKRU: 55555554<br /> Call Trace:<br /> __wake_up_common_lock+0x7c/0xc0<br /> qla_nvme_ls_req+0x355/0x4c0 [qla2xxx]<br /> 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<br /> ? __nvme_fc_send_ls_req+0x260/0x380 [nvme_fc]<br /> qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:00:02:ac:07:ee:b8 state transitioned from ONLINE to LOST - portid=010200.<br /> ? nvme_fc_send_ls_req.constprop.42+0x1a/0x45 [nvme_fc]<br /> qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320002ac07eeb8. rport ffff8ae598122000 roles 1<br /> ? nvme_fc_connect_ctrl_work.cold.63+0x1e3/0xa7d [nvme_fc]<br /> 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<br /> ? __switch_to+0x10c/0x450<br /> ? process_one_work+0x1a7/0x360<br /> qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:01:02:ad:f7:ee:b8 state transitioned from ONLINE to LOST - portid=010201.<br /> ? worker_thread+0x1ce/0x390<br /> ? create_worker+0x1a0/0x1a0<br /> qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320102adf7eeb8. rport ffff8ae3b2312800 roles 70<br /> ? kthread+0x10a/0x120<br /> qla2xxx [0000:12:00.1]-2112:3: qla_nvme_unregister_remote_port: unregister remoteport on ffff8ae14801e000 21320102adf7eeb8<br /> ? set_kthread_struct+0x40/0x40<br /> qla2xxx [0000:12:00.1]-2110:3: remoteport_delete of ffff8ae14801e000 21320102adf7eeb8 completed.<br /> ? ret_from_fork+0x1f/0x40<br /> qla2xxx [0000:12:00.1]-f086:3: qlt_free_session_done: waiting for sess ffff8ae14801e000 logout<br /> <br /> The system was under memory stress where driver was not able to allocate an<br /> SRB to carry out error recovery of cable pull. The failure to flush causes<br /> upper layer to start modifying scsi_cmnd. When the system frees up some<br /> memory, the subsequent cable pull trigger another command flush. At this<br /> point the driver access a null pointer when attempting to DMA unmap the<br /> SGL.<br /> <br /> Add a check to make sure commands are flush back on session tear down to<br /> prevent the null pointer access.