CVE-2021-47576

scsi: scsi_debug: Sanity check block descriptor length in resp_mode_select()

HIGH

7.8

CVSS Score

Published: June 19, 2024 at 02:53 PM UTC

Updated: August 5, 2026 at 09:24 AM UTC

1 product affected across 1 vendorLinux Kernel

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Severity

HIGH7.8

Exploit prediction

EPSS 0.3%

SSVC

No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_debug: Sanity check block descriptor length in resp_mode_select() In resp_mode_select() sanity check the block descriptor len to avoid UAF. BUG: KASAN: use-after-free in resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509 Read of size 1 at addr ffff888026670f50 by task scsicmd/15032 CPU: 1 PID: 15032 Comm: scsicmd Not tainted 5.15.0-01d0625 #15 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Call Trace: <TASK> dump_stack_lvl+0x89/0xb5 lib/dump_stack.c:107 print_address_description.constprop.9+0x28/0x160 mm/kasan/report.c:257 kasan_report.cold.14+0x7d/0x117 mm/kasan/report.c:443 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509 schedule_resp+0x4af/0x1a10 drivers/scsi/scsi_debug.c:5483 scsi_debug_queuecommand+0x8c9/0x1e70 drivers/scsi/scsi_debug.c:7537 scsi_queue_rq+0x16b4/0x2d10 drivers/scsi/scsi_lib.c:1521 blk_mq_dispatch_rq_list+0xb9b/0x2700 block/blk-mq.c:1640 __blk_mq_sched_dispatch_requests+0x28f/0x590 block/blk-mq-sched.c:325 blk_mq_sched_dispatch_requests+0x105/0x190 block/blk-mq-sched.c:358 __blk_mq_run_hw_queue+0xe5/0x150 block/blk-mq.c:1762 __blk_mq_delay_run_hw_queue+0x4f8/0x5c0 block/blk-mq.c:1839 blk_mq_run_hw_queue+0x18d/0x350 block/blk-mq.c:1891 blk_mq_sched_insert_request+0x3db/0x4e0 block/blk-mq-sched.c:474 blk_execute_rq_nowait+0x16b/0x1c0 block/blk-exec.c:63 sg_common_write.isra.18+0xeb3/0x2000 drivers/scsi/sg.c:837 sg_new_write.isra.19+0x570/0x8c0 drivers/scsi/sg.c:775 sg_ioctl_common+0x14d6/0x2710 drivers/scsi/sg.c:941 sg_ioctl+0xa2/0x180 drivers/scsi/sg.c:1166 __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:52 do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:50 entry_SYSCALL_64_after_hwframe+0x44/0xae arch/x86/entry/entry_64.S:113

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Linux Kernel · Linux

95%

v < 4.9.2942.6.19 ≤ v < 4.14.2592.6.19 ≤ v < 4.19.2222.6.19 ≤ v < 4.9.2942.6.19 ≤ v < 5.10.882.6.19 ≤ v < 5.15.112.6.19 ≤ v < 5.162.6.19 ≤ v < 5.4.1684.10 ≤ v < 4.14.2594.15 ≤ v < 4.19.2224.20 ≤ v < 5.4.1685.11 ≤ v < 5.15.115.5 ≤ v < 5.10.882.6.19231839102b54512ced7d3ee7fc9b8bcf5e3b583b

Vendor states this is fixed in 04181973c38f3d6a353f9246dcf7fee08024fd9e (fixed)

Vendor states this is fixed in 90491283b4064220682e4b0687d07b05df01e3bf (fixed)

Vendor states this is fixed in a9078e791426c2cbbdf28a320c3670f6e0a611e6 (fixed)

Vendor states this is fixed in adcecd50da6cab7b4957cba0606771dcc846c5a9 (fixed)

Vendor states this is fixed in b847ecff850719c46c95acd25a0d555dfd16e10d (fixed)

Vendor states this is fixed in dfc3fff63793c571147930b13c0f8c689c4281ac (fixed)

Vendor states this is fixed in e0a2c28da11e2c2b963fc01d50acbf03045ac732 (fixed)

Vendor states this is fixed in 2.6.19 (unaffected)

Vendor states this is fixed in 4.14.259 (unaffected)

Vendor states this is fixed in 4.19.222 (unaffected)

Vendor states this is fixed in 4.9.294 (unaffected)

Vendor states this is fixed in 5.10.88 (unaffected)

Vendor states this is fixed in 5.15.11 (unaffected)

Vendor states this is fixed in 5.16 (unaffected)

Vendor states this is fixed in 5.4.168 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references