scsi: scsi_debug: Fix out-of-bound read in resp_report_tgtpgs()
The following issue was observed running syzkaller:
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:377 [inline]
BUG: KASAN: slab-out-of-bounds in sg_copy_buffer+0x150/0x1c0 lib/scatterlist.c:831
Read of size 2132 at addr ffff8880aea95dc8 by task syz-executor.0/9815
CPU: 0 PID: 9815 Comm: syz-executor.0 Not tainted 4.19.202-00874-gfc0fe04215a9 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xe4/0x14a lib/dump_stack.c:118
print_address_description+0x73/0x280 mm/kasan/report.c:253
kasan_report_error mm/kasan/report.c:352 [inline]
kasan_report+0x272/0x370 mm/kasan/report.c:410
memcpy+0x1f/0x50 mm/kasan/kasan.c:302
memcpy include/linux/string.h:377 [inline]
sg_copy_buffer+0x150/0x1c0 lib/scatterlist.c:831
fill_from_dev_buffer+0x14f/0x340 drivers/scsi/scsi_debug.c:1021
resp_report_tgtpgs+0x5aa/0x770 drivers/scsi/scsi_debug.c:1772
schedule_resp+0x464/0x12f0 drivers/scsi/scsi_debug.c:4429
scsi_debug_queuecommand+0x467/0x1390 drivers/scsi/scsi_debug.c:5835
scsi_dispatch_cmd+0x3fc/0x9b0 drivers/scsi/scsi_lib.c:1896
scsi_request_fn+0x1042/0x1810 drivers/scsi/scsi_lib.c:2034
__blk_run_queue_uncond block/blk-core.c:464 [inline]
__blk_run_queue+0x1a4/0x380 block/blk-core.c:484
blk_execute_rq_nowait+0x1c2/0x2d0 block/blk-exec.c:78
sg_common_write.isra.19+0xd74/0x1dc0 drivers/scsi/sg.c:847
sg_write.part.23+0x6e0/0xd00 drivers/scsi/sg.c:716
sg_write+0x64/0xa0 drivers/scsi/sg.c:622
__vfs_write+0xed/0x690 fs/read_write.c:485
kill_bdev:block_device:00000000e138492c
vfs_write+0x184/0x4c0 fs/read_write.c:549
ksys_write+0x107/0x240 fs/read_write.c:599
do_syscall_64+0xc2/0x560 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
We get 'alen' from command its type is int. If userspace passes a large
length we will get a negative 'alen'.
Switch n, alen, and rlen to u32.
Analysis and contextual insights are available on OpenCVE Cloud.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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| Source | ID | Title |
|---|---|---|
Ubuntu USN |
USN-7391-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7392-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7392-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7392-3 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7392-4 | Linux kernel (AWS FIPS) vulnerabilities |
Ubuntu USN |
USN-7393-1 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7401-1 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7413-1 | Linux kernel (IoT) vulnerabilities |
Ubuntu USN |
USN-7463-1 | Linux kernel (IBM) vulnerabilities |
Ubuntu USN |
USN-7496-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7496-2 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7496-3 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7496-4 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7496-5 | Linux kernel (Azure FIPS) vulnerabilities |
Ubuntu USN |
USN-7506-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7506-2 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7506-3 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7506-4 | Linux kernel (Xenial HWE) vulnerabilities |
Ubuntu USN |
USN-7539-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7540-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Tue, 09 Dec 2025 21:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
Mon, 04 Nov 2024 12:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-05-11T13:50:17.180Z
Reserved: 2024-04-10T18:59:19.528Z
Link: CVE-2021-47219
Updated: 2024-08-04T05:32:07.367Z
Status : Awaiting Analysis
Published: 2024-04-10T19:15:48.903
Modified: 2024-11-21T06:35:39.137
Link: CVE-2021-47219
OpenCVE Enrichment
Updated: 2025-07-12T22:31:11Z
Ubuntu USN