CVE-2021-47261

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The vulnerable path is mlx5 kernel CQ resize via ib_resize_cq()/mlx5_ib_resize_cq with udata==NULL, reached from local RDMA ULP connection setup, not from unauthenticated remote packet processing.\nAC:L - Enlarging a kernel CQ reliably exercises the buggy init loop; the attacker (or ULP acting on their behalf) chooses the larger entry count, with no race or attacker-uncontrollable condition required.\nPR:L - In the realistic deployment shown by the crash (RDMA ULP calling ib_resize_cq during client connection setup), unprivileged local workloads can drive that connection path; uverbs devices are also world-accessible (0666), and when uncertain between PR:L and PR:H the higher severity applies.\nUI:N - No separate victim action is required; the attacker\u2019s own local activity that causes kernel CQ enlargement triggers the bug.\nS:U - Impact is kernel memory corruption within the host kernel security authority; this is not a VM escape, IOMMU bypass, or other cross-boundary issue.\nC:H - Out-of-bounds indexing of cq->buf.fbc.frags yields a corrupted pointer write into kernel memory; per guidance, exploitable memory corruption supports high confidentiality impact.\nI:H - This is an out-of-bounds write through an attacker-influenced frag index into kernel memory, which can be leveraged for integrity compromise and control-flow hijacking.\nA:H - The commit documents a kernel panic in init_cq_frag_buf when enlarging the CQ, which is high availability impact."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/infiniband/hw/mlx5/cq.c"], "versions": [{"version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "1ec2dcd680c71d0d36fa25638b327a468babd5c9", "status": "affected", "versionType": "git"}, {"version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26", "status": "affected", "versionType": "git"}, {"version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "91f7fdc4cc10542ca1045c06aad23365f0d067e0", "status": "affected", "versionType": "git"}, {"version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "3e670c54eda238cb8a1ea93538a79ae89285c1c4", "status": "affected", "versionType": "git"}, {"version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/infiniband/hw/mlx5/cq.c"], "versions": [{"version": "4.17", "status": "affected"}, {"version": "0", "lessThan": "4.17", "status": "unaffected", "versionType": "semver"}, {"version": "4.19.195", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.4.126", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.44", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.12.11", "lessThanOrEqual": "5.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.13", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.17", "versionEndExcluding": "4.19.195"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.17", "versionEndExcluding": "5.4.126"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.17", "versionEndExcluding": "5.10.44"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.17", "versionEndExcluding": "5.12.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.17", "versionEndExcluding": "5.13"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/1ec2dcd680c71d0d36fa25638b327a468babd5c9"}, {"url": "https://git.kernel.org/stable/c/e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26"}, {"url": "https://git.kernel.org/stable/c/91f7fdc4cc10542ca1045c06aad23365f0d067e0"}, {"url": "https://git.kernel.org/stable/c/3e670c54eda238cb8a1ea93538a79ae89285c1c4"}, {"url": "https://git.kernel.org/stable/c/2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a"}], "title": "IB/mlx5: Fix initializing CQ fragments buffer", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2021-47261", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-05-21T18:50:22.252363Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-06-04T17:14:42.110Z"}}, {"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:32:07.928Z"}, "title": "CVE Program Container", "references": [{"url": "https://git.kernel.org/stable/c/1ec2dcd680c71d0d36fa25638b327a468babd5c9", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/91f7fdc4cc10542ca1045c06aad23365f0d067e0", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/3e670c54eda238cb8a1ea93538a79ae89285c1c4", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a", "tags": ["x_transferred"]}]}]}}

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"version": "2.0.3", "timestamp": "2024-05-21T18:50:22.252363Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-05-23T19:01:25.507Z"}, "title": "CISA ADP Vulnrichment"}], "cna": {"title": "IB/mlx5: Fix initializing CQ fragments buffer", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.8, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable path is mlx5 kernel CQ resize via ib_resize_cq()/mlx5_ib_resize_cq with udata==NULL, reached from local RDMA ULP connection setup, not from unauthenticated remote packet processing.\nAC:L - Enlarging a kernel CQ reliably exercises the buggy init loop; the attacker (or ULP acting on their behalf) chooses the larger entry count, with no race or attacker-uncontrollable condition required.\nPR:L - In the realistic deployment shown by the crash (RDMA ULP calling ib_resize_cq during client connection setup), unprivileged local workloads can drive that connection path; uverbs devices are also world-accessible (0666), and when uncertain between PR:L and PR:H the higher severity applies.\nUI:N - No separate victim action is required; the attacker\u2019s own local activity that causes kernel CQ enlargement triggers the bug.\nS:U - Impact is kernel memory corruption within the host kernel security authority; this is not a VM escape, IOMMU bypass, or other cross-boundary issue.\nC:H - Out-of-bounds indexing of cq->buf.fbc.frags yields a corrupted pointer write into kernel memory; per guidance, exploitable memory corruption supports high confidentiality impact.\nI:H - This is an out-of-bounds write through an attacker-influenced frag index into kernel memory, which can be leveraged for integrity compromise and control-flow hijacking.\nA:H - The commit documents a kernel panic in init_cq_frag_buf when enlarging the CQ, which is high availability impact."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "1ec2dcd680c71d0d36fa25638b327a468babd5c9", "versionType": "git"}, {"status": "affected", "version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26", "versionType": "git"}, {"status": "affected", "version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "91f7fdc4cc10542ca1045c06aad23365f0d067e0", "versionType": "git"}, {"status": "affected", "version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "3e670c54eda238cb8a1ea93538a79ae89285c1c4", "versionType": "git"}, {"status": "affected", "version": "388ca8be00370db132464e27f745b8a0add19fcb", "lessThan": "2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a", "versionType": "git"}], "programFiles": ["drivers/infiniband/hw/mlx5/cq.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "4.17"}, {"status": "unaffected", "version": "0", "lessThan": "4.17", "versionType": "semver"}, {"status": "unaffected", "version": "4.19.195", "versionType": "semver", "lessThanOrEqual": "4.19.*"}, {"status": "unaffected", "version": "5.4.126", "versionType": "semver", "lessThanOrEqual": "5.4.*"}, {"status": "unaffected", "version": "5.10.44", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.12.11", "versionType": "semver", "lessThanOrEqual": "5.12.*"}, {"status": "unaffected", "version": "5.13", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["drivers/infiniband/hw/mlx5/cq.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/1ec2dcd680c71d0d36fa25638b327a468babd5c9"}, {"url": "https://git.kernel.org/stable/c/e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26"}, {"url": "https://git.kernel.org/stable/c/91f7fdc4cc10542ca1045c06aad23365f0d067e0"}, {"url": "https://git.kernel.org/stable/c/3e670c54eda238cb8a1ea93538a79ae89285c1c4"}, {"url": "https://git.kernel.org/stable/c/2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nIB/mlx5: Fix initializing CQ fragments buffer\n\nThe function init_cq_frag_buf() can be called to initialize the current CQ\nfragments buffer cq->buf, or the temporary cq->resize_buf that is filled\nduring CQ resize operation.\n\nHowever, the offending commit started to use function get_cqe() for\ngetting the CQEs, the issue with this change is that get_cqe() always\nreturns CQEs from cq->buf, which leads us to initialize the wrong buffer,\nand in case of enlarging the CQ we try to access elements beyond the size\nof the current cq->buf and eventually hit a kernel panic.\n\n [exception RIP: init_cq_frag_buf+103]\n [ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib]\n [ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core]\n [ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt]\n [ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt]\n [ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt]\n [ffff9f799ddcbec8] kthread at ffffffffa66c5da1\n [ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd\n\nFix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that\ntakes the correct source buffer as a parameter."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.19.195", "versionStartIncluding": "4.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, 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"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "5017B18F-E493-4424-A351-A210614CF65E", "versionEndExcluding": "4.19.195", "versionStartIncluding": "4.17", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "876275F9-BEC7-40E8-9D7F-A20729A4A4FF", "versionEndExcluding": "5.4.126", "versionStartIncluding": "4.20", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "DA547B08-9D25-467B-AD0D-8460FE4EE70D", "versionEndExcluding": "5.10.44", "versionStartIncluding": "5.5", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "F914A757-FAFD-407E-9031-21F66635D5EA", "versionEndExcluding": "5.12.11", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*", "matchCriteriaId": "0CBAD0FC-C281-4666-AB2F-F8E6E1165DF7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*", "matchCriteriaId": "96AC23B2-D46A-49D9-8203-8E1BEDCA8532", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*", "matchCriteriaId": "DA610E30-717C-4700-9F77-A3C9244F3BFD", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*", "matchCriteriaId": "1ECD33F5-85BE-430B-8F86-8D7BD560311D", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*", "matchCriteriaId": "CF351855-2437-4CF5-AD7C-BDFA51F27683", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nIB/mlx5: Fix initializing CQ fragments buffer\n\nThe function init_cq_frag_buf() can be called to initialize the current CQ\nfragments buffer cq->buf, or the temporary cq->resize_buf that is filled\nduring CQ resize operation.\n\nHowever, the offending commit started to use function get_cqe() for\ngetting the CQEs, the issue with this change is that get_cqe() always\nreturns CQEs from cq->buf, which leads us to initialize the wrong buffer,\nand in case of enlarging the CQ we try to access elements beyond the size\nof the current cq->buf and eventually hit a kernel panic.\n\n [exception RIP: init_cq_frag_buf+103]\n [ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib]\n [ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core]\n [ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt]\n [ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt]\n [ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt]\n [ffff9f799ddcbec8] kthread at ffffffffa66c5da1\n [ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd\n\nFix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that\ntakes the correct source buffer as a parameter."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: IB/mlx5: Correcci\u00f3n al inicializar el b\u00fafer de fragmentos CQ. Se puede llamar a la funci\u00f3n init_cq_frag_buf() para inicializar el b\u00fafer de fragmentos CQ actual cq->buf, o el cq->resize_buf temporal que es rellenado durante la operaci\u00f3n de cambio de tama\u00f1o de CQ. Sin embargo, la confirmaci\u00f3n infractora comenz\u00f3 a usar la funci\u00f3n get_cqe() para obtener los CQE, el problema con este cambio es que get_cqe() siempre devuelve CQE desde cq->buf, lo que nos lleva a inicializar el b\u00fafer incorrecto y, en caso de ampliarlo, En el CQ intentamos acceder a elementos m\u00e1s all\u00e1 del tama\u00f1o del cq->buf actual y finalmente entramos en p\u00e1nico en el kernel. [excepci\u00f3n RIP: init_cq_frag_buf+103] [ffff9f799ddcbcd8] mlx5_ib_resize_cq en fffffffc0835d60 [mlx5_ib] [ffff9f799ddcbdb0] ib_resize_cq en fffffffc05270df [ib_core] [ffff9f799ddcbdc0] _rdma_setup_qp en ffffffffc0a6a712 [llt] [ffff9f799ddcbe10] llt_rdma_cc_event_action en ffffffffc0a6b411 [llt] [ffff9f799ddcbe98] llt_rdma_client_conn_thread en ffffffffc0a6bb75 [llt] [ffff9f799ddcbec8] kthread en ffffffffa66c5da1 [ffff9f799ddcbf50] ret_from_fork_nospec_begin en ffffffffa6d95ddd Arr\u00e9glelo obteniendo el CQE necesario llamando a mlx5_frag_buf_get_wqe() que toma el b\u00fafer de origen correcto como par\u00e1metro."}], "id": "CVE-2021-47261", "lastModified": "2026-08-04T10:16:55.687", "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": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"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"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-47261", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-05-21T18:50:22.252363Z", "version": "2.0.3"}}]}, "published": "2024-05-21T15:15:14.770", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1ec2dcd680c71d0d36fa25638b327a468babd5c9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3e670c54eda238cb8a1ea93538a79ae89285c1c4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/91f7fdc4cc10542ca1045c06aad23365f0d067e0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1ec2dcd680c71d0d36fa25638b327a468babd5c9"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3e670c54eda238cb8a1ea93538a79ae89285c1c4"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/91f7fdc4cc10542ca1045c06aad23365f0d067e0"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-706"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: IB/mlx5: Fix initializing CQ fragments buffer", "id": "2282546", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2282546"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-665", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nIB/mlx5: Fix initializing CQ fragments buffer\nThe function init_cq_frag_buf() can be called to initialize the current CQ\nfragments buffer cq->buf, or the temporary cq->resize_buf that is filled\nduring CQ resize operation.\nHowever, the offending commit started to use function get_cqe() for\ngetting the CQEs, the issue with this change is that get_cqe() always\nreturns CQEs from cq->buf, which leads us to initialize the wrong buffer,\nand in case of enlarging the CQ we try to access elements beyond the size\nof the current cq->buf and eventually hit a kernel panic.\n[exception RIP: init_cq_frag_buf+103]\n[ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib]\n[ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core]\n[ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt]\n[ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt]\n[ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt]\n[ffff9f799ddcbec8] kthread at ffffffffa66c5da1\n[ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd\nFix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that\ntakes the correct source buffer as a parameter."], "name": "CVE-2021-47261", "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": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-05-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47261\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47261\nhttps://lore.kernel.org/linux-cve-announce/2024052147-CVE-2021-47261-20fd@gregkh/T"], "threat_severity": "Low"}

{}