ghsa-f3gg-6f8f-39gh
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
vhost/scsi: null-ptr-dereference in vhost_scsi_get_req()
Since commit 3f8ca2e115e5 ("vhost/scsi: Extract common handling code from control queue handler") a null pointer dereference bug can be triggered when guest sends an SCSI AN request.
In vhost_scsi_ctl_handle_vq(), vc.target is assigned with
&v_req.tmf.lun[1] within a switch-case block and is then passed to
vhost_scsi_get_req() which extracts vc->req and tpg. However, for
a VIRTIO_SCSI_T_AN_* request, tpg is not required, so vc.target is
set to NULL in this branch. Later, in vhost_scsi_get_req(),
vc->target is dereferenced without being checked, leading to a null
pointer dereference bug. This bug can be triggered from guest.
When this bug occurs, the vhost_worker process is killed while holding
vq->mutex and the corresponding tpg will remain occupied
indefinitely.
Below is the KASAN report: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 840 Comm: poc Not tainted 6.10.0+ #1 Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:vhost_scsi_get_req+0x165/0x3a0 Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 2b 02 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 65 30 4c 89 e2 48 c1 ea 03 <0f> b6 04 02 4c 89 e2 83 e2 07 38 d0 7f 08 84 c0 0f 85 be 01 00 00 RSP: 0018:ffff888017affb50 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88801b000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888017affcb8 RBP: ffff888017affb80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888017affc88 R14: ffff888017affd1c R15: ffff888017993000 FS: 000055556e076500(0000) GS:ffff88806b100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200027c0 CR3: 0000000010ed0004 CR4: 0000000000370ef0 Call Trace: ? show_regs+0x86/0xa0 ? die_addr+0x4b/0xd0 ? exc_general_protection+0x163/0x260 ? asm_exc_general_protection+0x27/0x30 ? vhost_scsi_get_req+0x165/0x3a0 vhost_scsi_ctl_handle_vq+0x2a4/0xca0 ? __pfx_vhost_scsi_ctl_handle_vq+0x10/0x10 ? __switch_to+0x721/0xeb0 ? __schedule+0xda5/0x5710 ? __kasan_check_write+0x14/0x30 ? _raw_spin_lock+0x82/0xf0 vhost_scsi_ctl_handle_kick+0x52/0x90 vhost_run_work_list+0x134/0x1b0 vhost_task_fn+0x121/0x350 ... ---[ end trace 0000000000000000 ]---
Let's add a check in vhost_scsi_get_req.
[whitespace fixes]
{
"affected": [],
"aliases": [
"CVE-2024-49863"
],
"database_specific": {
"cwe_ids": [
"CWE-476"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-10-21T18:15:06Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvhost/scsi: null-ptr-dereference in vhost_scsi_get_req()\n\nSince commit 3f8ca2e115e5 (\"vhost/scsi: Extract common handling code\nfrom control queue handler\") a null pointer dereference bug can be\ntriggered when guest sends an SCSI AN request.\n\nIn vhost_scsi_ctl_handle_vq(), `vc.target` is assigned with\n`\u0026v_req.tmf.lun[1]` within a switch-case block and is then passed to\nvhost_scsi_get_req() which extracts `vc-\u003ereq` and `tpg`. However, for\na `VIRTIO_SCSI_T_AN_*` request, tpg is not required, so `vc.target` is\nset to NULL in this branch. Later, in vhost_scsi_get_req(),\n`vc-\u003etarget` is dereferenced without being checked, leading to a null\npointer dereference bug. This bug can be triggered from guest.\n\nWhen this bug occurs, the vhost_worker process is killed while holding\n`vq-\u003emutex` and the corresponding tpg will remain occupied\nindefinitely.\n\nBelow is the KASAN report:\nOops: general protection fault, probably for non-canonical address\n0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI\nKASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\nCPU: 1 PID: 840 Comm: poc Not tainted 6.10.0+ #1\nHardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS\n1.16.3-debian-1.16.3-2 04/01/2014\nRIP: 0010:vhost_scsi_get_req+0x165/0x3a0\nCode: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 2b 02 00 00\n48 b8 00 00 00 00 00 fc ff df 4d 8b 65 30 4c 89 e2 48 c1 ea 03 \u003c0f\u003e b6\n04 02 4c 89 e2 83 e2 07 38 d0 7f 08 84 c0 0f 85 be 01 00 00\nRSP: 0018:ffff888017affb50 EFLAGS: 00010246\nRAX: dffffc0000000000 RBX: ffff88801b000000 RCX: 0000000000000000\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888017affcb8\nRBP: ffff888017affb80 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000\nR13: ffff888017affc88 R14: ffff888017affd1c R15: ffff888017993000\nFS: 000055556e076500(0000) GS:ffff88806b100000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00000000200027c0 CR3: 0000000010ed0004 CR4: 0000000000370ef0\nCall Trace:\n \u003cTASK\u003e\n ? show_regs+0x86/0xa0\n ? die_addr+0x4b/0xd0\n ? exc_general_protection+0x163/0x260\n ? asm_exc_general_protection+0x27/0x30\n ? vhost_scsi_get_req+0x165/0x3a0\n vhost_scsi_ctl_handle_vq+0x2a4/0xca0\n ? __pfx_vhost_scsi_ctl_handle_vq+0x10/0x10\n ? __switch_to+0x721/0xeb0\n ? __schedule+0xda5/0x5710\n ? __kasan_check_write+0x14/0x30\n ? _raw_spin_lock+0x82/0xf0\n vhost_scsi_ctl_handle_kick+0x52/0x90\n vhost_run_work_list+0x134/0x1b0\n vhost_task_fn+0x121/0x350\n...\n \u003c/TASK\u003e\n---[ end trace 0000000000000000 ]---\n\nLet\u0027s add a check in vhost_scsi_get_req.\n\n[whitespace fixes]",
"id": "GHSA-f3gg-6f8f-39gh",
"modified": "2024-10-24T21:31:01Z",
"published": "2024-10-21T18:30:56Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-49863"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/00fb5b23e1c9cdbe496f5cd6b40367cb895f6c93"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/221af82f606d928ccef19a16d35633c63026f1be"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/25613e6d9841a1f9fb985be90df921fa99f800de"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/46128370a72c431df733af5ebb065c4d48c9ad39"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/61517f33e76d2c5247c1e61e668693afe5b67e6f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6592347f06e2b19a624270a85ad4b3ae48c3b241"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ace9c778a214da9c98d7b69d904d1b0816f4f681"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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