CVE-2021-47649

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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/dma-buf/udmabuf.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "5d50f851dd307c07ca5591297093f19967c834a9", "status": "affected", "version": "fbb0de795078190a9834b3409e4b009cfb18a6d4", "versionType": "git"}, {"lessThan": "b267a8118c2b171bf7d67b90ed64154eeab9fae0", "status": "affected", "version": "fbb0de795078190a9834b3409e4b009cfb18a6d4", "versionType": "git"}, {"lessThan": "811b667cefbea9cb7511a874b169d6a92907137e", "status": "affected", "version": "fbb0de795078190a9834b3409e4b009cfb18a6d4", "versionType": "git"}, {"lessThan": "a3728d32fc61eb0fe283cb8ff60b2c8f751e2202", "status": "affected", "version": "fbb0de795078190a9834b3409e4b009cfb18a6d4", "versionType": "git"}, {"lessThan": "9e9b4a269f84d3230f2af84ff42322db676440d9", "status": "affected", "version": "fbb0de795078190a9834b3409e4b009cfb18a6d4", "versionType": "git"}, {"lessThan": "2b6dd600dd72573c23ea180b5b0b2f1813405882", "status": "affected", "version": "fbb0de795078190a9834b3409e4b009cfb18a6d4", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/dma-buf/udmabuf.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "4.20"}, {"lessThan": "4.20", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.4.*", "status": "unaffected", "version": "5.4.189", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.110", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.33", "versionType": "semver"}, {"lessThanOrEqual": "5.16.*", "status": "unaffected", "version": "5.16.19", "versionType": "semver"}, {"lessThanOrEqual": "5.17.*", "status": "unaffected", "version": "5.17.2", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "5.18", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "8CB6E8F5-C2B1-46F3-A807-0F6104AC340F", "versionEndExcluding": "5.4.189", "versionStartIncluding": "4.20", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "91D3BFD0-D3F3-4018-957C-96CCBF357D79", "versionEndExcluding": "5.10.110", "versionStartIncluding": "5.5", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "27C42AE8-B387-43E2-938A-E1C8B40BE6D5", "versionEndExcluding": "5.15.33", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "20C43679-0439-405A-B97F-685BEE50613B", "versionEndExcluding": "5.16.19", "versionStartIncluding": "5.16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "210C679C-CF84-44A3-8939-E629C87E54BF", "versionEndExcluding": "5.17.2", "versionStartIncluding": "5.17", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nudmabuf: validate ubuf->pagecount\n\nSyzbot has reported GPF in sg_alloc_append_table_from_pages(). The\nproblem was in ubuf->pages == ZERO_PTR.\n\nubuf->pagecount is calculated from arguments passed from user-space. If\nuser creates udmabuf with list.size == 0 then ubuf->pagecount will be\nalso equal to zero; it causes kmalloc_array() to return ZERO_PTR.\n\nFix it by validating ubuf->pagecount before passing it to\nkmalloc_array()."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: udmabuf: validar ubuf->pagecount Syzbot ha informado de un GPF en sg_alloc_append_table_from_pages(). El problema estaba en ubuf->pages == ZERO_PTR. ubuf->pagecount se calcula a partir de los argumentos pasados desde el espacio de usuario. Si el usuario crea udmabuf con list.size == 0, entonces ubuf->pagecount tambi\u00e9n ser\u00e1 igual a cero; esto hace que kmalloc_array() devuelva ZERO_PTR. Arr\u00e9glelo validando ubuf->pagecount antes de pasarlo a kmalloc_array()."}], "id": "CVE-2021-47649", "lastModified": "2026-06-17T04:18:14.647", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2025-02-26T06:37:06.687", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2b6dd600dd72573c23ea180b5b0b2f1813405882"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/5d50f851dd307c07ca5591297093f19967c834a9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/811b667cefbea9cb7511a874b169d6a92907137e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/9e9b4a269f84d3230f2af84ff42322db676440d9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a3728d32fc61eb0fe283cb8ff60b2c8f751e2202"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b267a8118c2b171bf7d67b90ed64154eeab9fae0"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"affected_release": [{"advisory": "RHSA-2022:7683", "cpe": "cpe:/o:redhat:enterprise_linux:8", "package": "kernel-0:4.18.0-425.3.1.el8", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2022-11-08T00:00:00Z"}, {"advisory": "RHSA-2022:8267", "cpe": "cpe:/a:redhat:enterprise_linux:9", "package": "kernel-0:5.14.0-162.6.1.el9_1", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2022-11-15T00:00:00Z"}, {"advisory": "RHSA-2022:8267", "cpe": "cpe:/o:redhat:enterprise_linux:9", "package": "kernel-0:5.14.0-162.6.1.el9_1", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2022-11-15T00:00:00Z"}], "bugzilla": {"description": "kernel: udmabuf: validate ubuf->pagecount", "id": "2348193", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2348193"}, "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"}, "details": ["In the Linux kernel, the following vulnerability has been resolved:\nudmabuf: validate ubuf->pagecount\nSyzbot has reported GPF in sg_alloc_append_table_from_pages(). The\nproblem was in ubuf->pages == ZERO_PTR.\nubuf->pagecount is calculated from arguments passed from user-space. If\nuser creates udmabuf with list.size == 0 then ubuf->pagecount will be\nalso equal to zero; it causes kmalloc_array() to return ZERO_PTR.\nFix it by validating ubuf->pagecount before passing it to\nkmalloc_array().", "A vulnerability was found in the Linux kernel in the `udmabuf_create()` function. An improper user-provided argument validation can lead to a `ZERO_PTR` value being passed to the sg_alloc_append_table_from_pages()` function, which attempts a dereference and leads to a kernel crash."], "name": "CVE-2021-47649", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-02-26T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47649\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47649\nhttps://lore.kernel.org/linux-cve-announce/2025022649-CVE-2021-47649-f358@gregkh/T"], "threat_severity": "Moderate"}

{}