{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98643", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.362Z", "datePublished": "2026-10-18T15:20:14.561Z", "dateUpdated": "2026-10-19T09:23:12.946Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:23:12.946Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix out-of-bounds read of rtt_min in sock_ops\n\nA sockops prog reading skops->rtt_min never checks the sk type: on the\ntcp_conn_request() path sock_ops->sk is a request_sock (non-full), and the\nctx rewrite casts it to a tcp_sock (full) and reads rtt_min past the end of\nthe request_sock, returning dirty adjacent memory.\n\n\tSEC(\"sockops\")\n\tint prog(struct bpf_sock_ops *skops)\n\t{\n\t\tswitch (skops->op) {\n\t\tcase BPF_SOCK_OPS_RWND_INIT:\n\t\t\tleak = skops->rtt_min; /* reads the request_sock OOB */\n\t\t...\n\t\t}\n\t}\n\nFor instance one such read returned rtt_min=0xffff8881, the high half of a\nleaked kernel pointer.\n\nGuarding that cast is exactly what SOCK_OPS_GET_FIELD() does -- it checks\nis_locked_tcp_sock and returns 0 when sock_ops->sk is not a locked full\nsocket. Every other tcp_sock field in sock_ops goes through it; rtt_min is\nthe only one open-coded, so it skips the check.\n\nRead rtt_min through SOCK_OPS_GET_FIELD() too. rtt_min is a bit special:\nit is a struct minmax and we only want the current min, so pass\nrtt_min.s[0].v. That is equivalent to the old hand-computed offset\n\n\toffsetof(struct tcp_sock, rtt_min) + sizeof_field(struct minmax_sample, t)\n\n(s[0] sits at rtt_min + 0 and .v at + sizeof(.t), i.e. what minmax_get()\nreturns), so the loaded field is unchanged and only the full-sock guard is\nadded. The two BUILD_BUG_ON()s that protected the hand-computed offset\nare no longer needed.\n\nBefore patch:\n\n\t0: r1 = *(u64 *)(r1 +0) ; r1 = skops->sk\n\t1: r1 = *(u32 *)(r1 +2324) ; ((tcp_sock *)sk)->rtt_min.s[0].v\n\nAfter patch:\n\n\t0: *(u64 *)(r1 +56) = r9\n\t1: r9 = *(u8 *)(r1 +50) ; is_locked_tcp_sock\n\t2: if r9 == 0 goto pc+4 ; not a locked full sock -> 0\n\t3: r9 = *(u64 *)(r1 +56)\n\t4: r1 = *(u64 *)(r1 +0) ; r1 = skops->sk\n\t5: r1 = *(u32 *)(r1 +2324) ; rtt_min.s[0].v\n\t6: goto pc+2\n\t7: r9 = *(u64 *)(r1 +56)\n\t8: r1 = 0" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/filter.c" ], "versions": [ { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "0c796efa919f52f788c22c79d1f1b70321696b3d", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "fc9d0e6e9d86fbefe7b8fe6ee49f4cf102add79d", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "fd6bf2721933d8c90bc4ce57f3e204c9295e7e3f", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "a8a9becbac93a9f54f4d565f1f3005eb08a7912f", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "3a46f14e6cf375f3ca38f8f6e6524749e24ea0a8", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "6785313d4fac96afb21ef193610c1fa88b1a9e64", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "cba54d142c43ec96d8c4d566f66439e8c0afded7", "status": "affected", "versionType": "git" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "lessThan": "75f8cf22463d82bb1fb0239a3d485fc8f4c8ef03", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/filter.c" ], "versions": [ { "version": "4.16", "status": "affected" }, { "version": "0", "lessThan": "4.16", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "4.16", "versionEndExcluding": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.18.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/0c796efa919f52f788c22c79d1f1b70321696b3d" }, { "url": "https://git.kernel.org/stable/c/fc9d0e6e9d86fbefe7b8fe6ee49f4cf102add79d" }, { "url": "https://git.kernel.org/stable/c/fd6bf2721933d8c90bc4ce57f3e204c9295e7e3f" }, { "url": "https://git.kernel.org/stable/c/a8a9becbac93a9f54f4d565f1f3005eb08a7912f" }, { "url": "https://git.kernel.org/stable/c/3a46f14e6cf375f3ca38f8f6e6524749e24ea0a8" }, { "url": "https://git.kernel.org/stable/c/6785313d4fac96afb21ef193610c1fa88b1a9e64" }, { "url": "https://git.kernel.org/stable/c/cba54d142c43ec96d8c4d566f66439e8c0afded7" }, { "url": "https://git.kernel.org/stable/c/75f8cf22463d82bb1fb0239a3d485fc8f4c8ef03" } ], "title": "bpf: Fix out-of-bounds read of rtt_min in sock_ops", "x_generator": { "engine": "bippy-1.2.0" } } } }