out-of-bounds read in scst_cmd_overlap_atomic

[pzwahlen]

Hi,

We are running an iSCSI target with SCST 3.9 on RockyLinux 9.6

Out of nowhere, I see this error in the kernel log:

==================================================================
BUG: KFENCE: out-of-bounds read in scst_cmd_overlap_atomic+0x119/0x150 [scst]

Out-of-bounds read at 0x000000008e0b9cd3 (40B right of kfence-#110):
 scst_cmd_overlap_atomic+0x119/0x150 [scst]
 scst_check_scsi_atomicity+0x70/0x1d0 [scst]
 scst_do_check_blocked_dev+0xd8/0xe0 [scst]
 scst_check_blocked_dev+0x34/0x70 [scst]
 scst_exec_check_blocking+0x40/0x210 [scst]
 scst_process_active_cmd+0x1e0/0x600 [scst]
 scst_cmd_thread+0x19d/0x640 [scst]
 kthread+0xdd/0x100
 ret_from_fork+0x29/0x50

kfence-#110: 0x0000000061a89ed0-0x000000009af78d29, size=32, cache=kmalloc-32

allocated by task 11510 on cpu 1 at 5100775.957811s:
 scst_parse_unmap_descriptors+0x89/0x1e0 [scst]
 scst_tgt_pre_exec+0x22b/0x2e0 [scst]
 scst_process_active_cmd+0x37f/0x600 [scst]
 scst_cmd_thread+0x19d/0x640 [scst]
 kthread+0xdd/0x100
 ret_from_fork+0x29/0x50

CPU: 6 PID: 11465 Comm: p01t71l012_6 Tainted: P S         OE  X  -------  ---  5.14.0-570.39.1.el9_6.x86_64 #1
Hardware name: Dell Inc. PowerEdge R620/0PXXHP, BIOS 2.9.0 12/06/2019
==================================================================

That happened only once and things seem to work fine.

Any reason to be worried ?