{"dataType": "CVE_RECORD", "dataVersion": "5.1", "cveMetadata": {"cveId": "CVE-2021-47566", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-05-24T15:11:00.728Z", "datePublished": "2024-05-24T15:12:53.432Z", "dateUpdated": "2025-05-04T07:13:47.049Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2025-05-04T07:13:47.049Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nproc/vmcore: fix clearing user buffer by properly using clear_user()\n\nTo clear a user buffer we cannot simply use memset, we have to use\nclear_user(). With a virtio-mem device that registers a vmcore_cb and\nhas some logically unplugged memory inside an added Linux memory block,\nI can easily trigger a BUG by copying the vmcore via \"cp\":\n\n systemd[1]: Starting Kdump Vmcore Save Service...\n kdump[420]: Kdump is using the default log level(3).\n kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\n kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\n kdump[465]: saving vmcore-dmesg.txt complete\n kdump[467]: saving vmcore\n BUG: unable to handle page fault for address: 00007f2374e01000\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0003) - permissions violation\n PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867\n Oops: 0003 [#1] PREEMPT SMP NOPTI\n CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014\n RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86\n Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81\n RSP: 0018:ffffc9000073be08 EFLAGS: 00010212\n RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000\n RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008\n RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50\n R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000\n R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8\n FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0\n Call Trace:\n read_vmcore+0x236/0x2c0\n proc_reg_read+0x55/0xa0\n vfs_read+0x95/0x190\n ksys_read+0x4f/0xc0\n do_syscall_64+0x3b/0x90\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nSome x86-64 CPUs have a CPU feature called \"Supervisor Mode Access\nPrevention (SMAP)\", which is used to detect wrong access from the kernel\nto user buffers like this: SMAP triggers a permissions violation on\nwrong access. In the x86-64 variant of clear_user(), SMAP is properly\nhandled via clac()+stac().\n\nTo fix, properly use clear_user() when we're dealing with a user buffer."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/proc/vmcore.c"], "versions": [{"version": "997c136f518c5debd63847e78e2a8694f56dcf90", "lessThan": "a9e164bd160be8cbee1df70acb379129e3cd2e7c", "status": "affected", "versionType": "git"}, {"version": "997c136f518c5debd63847e78e2a8694f56dcf90", "lessThan": "33a7d698f30fa0b99d50569e9909d3baa65d8f6a", "status": "affected", "versionType": "git"}, {"version": "997c136f518c5debd63847e78e2a8694f56dcf90", "lessThan": "99d348b82bcb36171f24411d3f1a15706a2a937a", "status": "affected", "versionType": "git"}, {"version": "997c136f518c5debd63847e78e2a8694f56dcf90", "lessThan": "9ef384ed300d1bcfb23d0ab0b487d544444d4b52", "status": "affected", "versionType": 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With a virtio-mem device that registers a vmcore_cb and\nhas some logically unplugged memory inside an added Linux memory block,\nI can easily trigger a BUG by copying the vmcore via \"cp\":\n\n systemd[1]: Starting Kdump Vmcore Save Service...\n kdump[420]: Kdump is using the default log level(3).\n kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\n kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\n kdump[465]: saving vmcore-dmesg.txt complete\n kdump[467]: saving vmcore\n BUG: unable to handle page fault for address: 00007f2374e01000\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0003) - permissions violation\n PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867\n Oops: 0003 [#1] PREEMPT SMP NOPTI\n CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014\n RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86\n Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81\n RSP: 0018:ffffc9000073be08 EFLAGS: 00010212\n RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000\n RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008\n RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50\n R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000\n R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8\n FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0\n Call Trace:\n read_vmcore+0x236/0x2c0\n proc_reg_read+0x55/0xa0\n vfs_read+0x95/0x190\n ksys_read+0x4f/0xc0\n do_syscall_64+0x3b/0x90\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nSome x86-64 CPUs have a CPU feature called \"Supervisor Mode Access\nPrevention (SMAP)\", which is used to detect wrong access from the kernel\nto user buffers like this: SMAP triggers a permissions violation on\nwrong access. In the x86-64 variant of clear_user(), SMAP is properly\nhandled via clac()+stac().\n\nTo fix, properly use clear_user() when we're dealing with a user buffer."}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2024-05-29T05:10:14.234Z"}}}, "cveMetadata": {"cveId": "CVE-2021-47566", "state": "PUBLISHED", "dateUpdated": "2024-08-04T05:39:59.769Z", "dateReserved": "2024-05-24T15:11:00.728Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-05-24T15:12:53.432Z", "assignerShortName": "Linux"}, "dataVersion": "5.1"}

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With a virtio-mem device that registers a vmcore_cb and\nhas some logically unplugged memory inside an added Linux memory block,\nI can easily trigger a BUG by copying the vmcore via \"cp\":\n\n systemd[1]: Starting Kdump Vmcore Save Service...\n kdump[420]: Kdump is using the default log level(3).\n kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\n kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\n kdump[465]: saving vmcore-dmesg.txt complete\n kdump[467]: saving vmcore\n BUG: unable to handle page fault for address: 00007f2374e01000\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0003) - permissions violation\n PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867\n Oops: 0003 [#1] PREEMPT SMP NOPTI\n CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014\n RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86\n Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81\n RSP: 0018:ffffc9000073be08 EFLAGS: 00010212\n RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000\n RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008\n RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50\n R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000\n R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8\n FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0\n Call Trace:\n read_vmcore+0x236/0x2c0\n proc_reg_read+0x55/0xa0\n vfs_read+0x95/0x190\n ksys_read+0x4f/0xc0\n do_syscall_64+0x3b/0x90\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nSome x86-64 CPUs have a CPU feature called \"Supervisor Mode Access\nPrevention (SMAP)\", which is used to detect wrong access from the kernel\nto user buffers like this: SMAP triggers a permissions violation on\nwrong access. In the x86-64 variant of clear_user(), SMAP is properly\nhandled via clac()+stac().\n\nTo fix, properly use clear_user() when we're dealing with a user buffer."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: proc/vmcore: corrige el borrado del b\u00fafer del usuario usando correctamente clear_user() Para borrar un b\u00fafer de usuario no podemos simplemente usar memset, tenemos que usar clear_user(). Con un dispositivo virtio-mem que registra un vmcore_cb y tiene algo de memoria l\u00f3gicamente desconectada dentro de un bloque de memoria de Linux agregado, puedo desencadenar f\u00e1cilmente un ERROR copiando el vmcore a trav\u00e9s de \"cp\": systemd[1]: Iniciando el servicio Kdump Vmcore Save. . kdump[420]: Kdump est\u00e1 utilizando el nivel de registro predeterminado (3). kdump[453]: guardar en /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[458]: guardar vmcore-dmesg.txt en /sysroot/var/crash/127.0 .0.1-2021-11-11-14:59:22/ kdump[465]: guardar vmcore-dmesg.txt completo kdump[467]: guardar vmcore ERROR: no se puede manejar el error de p\u00e1gina para la direcci\u00f3n: 00007f2374e01000 #PF: escritura del supervisor acceso en modo kernel #PF: error_code(0x0003) - violaci\u00f3n de permisos PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867 Ups: 0003 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 468 Comm: p No contaminado 5.15.0+ # 6 Nombre del hardware: PC est\u00e1ndar QEMU (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 01/04/2014 RIP: 0010:read_from_oldmem.part.0.cold+0x1d/ 0x86 C\u00f3digo: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 &lt;49&gt; c7 45 00 00 00 00 00 49 C7 44 05 F8 00 00 00 00 48 83 E7 F81 RSP: 0018: FFFFFC9000073BE08 EFLAGS: 00010212 RAX: 00000000000000001000 RBX: 000000002FD000 RCX: 00007F2374E RSI: 000000000000FFFFDFFF RDI: 00007F2374E01008 RBP: 000000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50 R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000 R13: 00007f2374e01000 R14: 0000000000000000 R15: 88807bd421e8 FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2 : 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0 Seguimiento de llamadas: read_vmcore+0x236/0x2c0 proc_reg_read+0x55/0xa0 vfs_read+0x95/0x190 do_syscall_64+0x3b/0x90 Entry_SYSCALL_64_after_hwframe+0x44/0xae Algunas CPU x86-64 tienen una funci\u00f3n de CPU llamada \"Prevenci\u00f3n de acceso en modo supervisor (SMAP)\", que se utiliza para detectar accesos incorrectos desde el kernel a los b\u00faferes de usuario como este: SMAP desencadena una violaci\u00f3n de permisos en caso de acceso incorrecto. En la variante x86-64 de clear_user(), SMAP se maneja correctamente mediante clac()+stac(). Para solucionarlo, utilice correctamente clear_user() cuando estemos tratando con un b\u00fafer de usuario."}], "id": "CVE-2021-47566", "lastModified": "2025-09-18T15:41:41.317", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2024-05-24T15:15:21.637", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/33a7d698f30fa0b99d50569e9909d3baa65d8f6a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/99d348b82bcb36171f24411d3f1a15706a2a937a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/9ef384ed300d1bcfb23d0ab0b487d544444d4b52"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a8a917058faf4abaec9fb614bb6d5f8fe3529ec6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a9e164bd160be8cbee1df70acb379129e3cd2e7c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c1e63117711977cc4295b2ce73de29dd17066c82"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/fd7974c547abfb03072a4ee706d3a6f182266f89"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/33a7d698f30fa0b99d50569e9909d3baa65d8f6a"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/99d348b82bcb36171f24411d3f1a15706a2a937a"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/9ef384ed300d1bcfb23d0ab0b487d544444d4b52"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a8a917058faf4abaec9fb614bb6d5f8fe3529ec6"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a9e164bd160be8cbee1df70acb379129e3cd2e7c"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c1e63117711977cc4295b2ce73de29dd17066c82"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/fd7974c547abfb03072a4ee706d3a6f182266f89"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-787"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"affected_release": [{"advisory": "RHSA-2024:5281", "cpe": "cpe:/o:redhat:rhel_aus:8.6", "package": "kernel-0:4.18.0-372.118.1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support", "release_date": "2024-08-13T00:00:00Z"}, {"advisory": "RHSA-2024:5281", "cpe": "cpe:/o:redhat:rhel_tus:8.6", "package": "kernel-0:4.18.0-372.118.1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Telecommunications Update Service", "release_date": "2024-08-13T00:00:00Z"}, {"advisory": "RHSA-2024:5281", "cpe": "cpe:/o:redhat:rhel_e4s:8.6", "package": "kernel-0:4.18.0-372.118.1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions", "release_date": "2024-08-13T00:00:00Z"}, {"advisory": "RHSA-2024:6993", "cpe": "cpe:/o:redhat:rhel_eus:8.8", "package": "kernel-0:4.18.0-477.74.1.el8_8", "product_name": "Red Hat Enterprise Linux 8.8 Extended Update Support", "release_date": "2024-09-24T00:00:00Z"}], "bugzilla": {"description": "kernel: proc/vmcore: fix clearing user buffer by properly using clear_user()", "id": "2283463", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2283463"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "verified"}, "cwe": "CWE-501", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nproc/vmcore: fix clearing user buffer by properly using clear_user()\nTo clear a user buffer we cannot simply use memset, we have to use\nclear_user(). With a virtio-mem device that registers a vmcore_cb and\nhas some logically unplugged memory inside an added Linux memory block,\nI can easily trigger a BUG by copying the vmcore via \"cp\":\nsystemd[1]: Starting Kdump Vmcore Save Service...\nkdump[420]: Kdump is using the default log level(3).\nkdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\nkdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/\nkdump[465]: saving vmcore-dmesg.txt complete\nkdump[467]: saving vmcore\nBUG: unable to handle page fault for address: 00007f2374e01000\n#PF: supervisor write access in kernel mode\n#PF: error_code(0x0003) - permissions violation\nPGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867\nOops: 0003 [#1] PREEMPT SMP NOPTI\nCPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014\nRIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86\nCode: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81\nRSP: 0018:ffffc9000073be08 EFLAGS: 00010212\nRAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000\nRDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008\nRBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50\nR10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000\nR13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8\nFS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0\nCall Trace:\nread_vmcore+0x236/0x2c0\nproc_reg_read+0x55/0xa0\nvfs_read+0x95/0x190\nksys_read+0x4f/0xc0\ndo_syscall_64+0x3b/0x90\nentry_SYSCALL_64_after_hwframe+0x44/0xae\nSome x86-64 CPUs have a CPU feature called \"Supervisor Mode Access\nPrevention (SMAP)\", which is used to detect wrong access from the kernel\nto user buffers like this: SMAP triggers a permissions violation on\nwrong access. In the x86-64 variant of clear_user(), SMAP is properly\nhandled via clac()+stac().\nTo fix, properly use clear_user() when we're dealing with a user buffer."], "name": "CVE-2021-47566", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-05-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47566\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47566\nhttps://lore.kernel.org/linux-cve-announce/2024052453-CVE-2021-47566-12b8@gregkh/T"], "threat_severity": "Low"}