| { |
| "containers": { |
| "cna": { |
| "providerMetadata": { |
| "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038" |
| }, |
| "descriptions": [ |
| { |
| "lang": "en", |
| "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: track changes_pkt_data property for global functions\n\nWhen processing calls to certain helpers, verifier invalidates all\npacket pointers in a current state. For example, consider the\nfollowing program:\n\n __attribute__((__noinline__))\n long skb_pull_data(struct __sk_buff *sk, __u32 len)\n {\n return bpf_skb_pull_data(sk, len);\n }\n\n SEC(\"tc\")\n int test_invalidate_checks(struct __sk_buff *sk)\n {\n int *p = (void *)(long)sk->data;\n if ((void *)(p + 1) > (void *)(long)sk->data_end) return TCX_DROP;\n skb_pull_data(sk, 0);\n *p = 42;\n return TCX_PASS;\n }\n\nAfter a call to bpf_skb_pull_data() the pointer 'p' can't be used\nsafely. See function filter.c:bpf_helper_changes_pkt_data() for a list\nof such helpers.\n\nAt the moment verifier invalidates packet pointers when processing\nhelper function calls, and does not traverse global sub-programs when\nprocessing calls to global sub-programs. This means that calls to\nhelpers done from global sub-programs do not invalidate pointers in\nthe caller state. E.g. the program above is unsafe, but is not\nrejected by verifier.\n\nThis commit fixes the omission by computing field\nbpf_subprog_info->changes_pkt_data for each sub-program before main\nverification pass.\nchanges_pkt_data should be set if:\n- subprogram calls helper for which bpf_helper_changes_pkt_data\n returns true;\n- subprogram calls a global function,\n for which bpf_subprog_info->changes_pkt_data should be set.\n\nThe verifier.c:check_cfg() pass is modified to compute this\ninformation. The commit relies on depth first instruction traversal\ndone by check_cfg() and absence of recursive function calls:\n- check_cfg() would eventually visit every call to subprogram S in a\n state when S is fully explored;\n- when S is fully explored:\n - every direct helper call within S is explored\n (and thus changes_pkt_data is set if needed);\n - every call to subprogram S1 called by S was visited with S1 fully\n explored (and thus S inherits changes_pkt_data from S1).\n\nThe downside of such approach is that dead code elimination is not\ntaken into account: if a helper call inside global function is dead\nbecause of current configuration, verifier would conservatively assume\nthat the call occurs for the purpose of the changes_pkt_data\ncomputation." |
| } |
| ], |
| "affected": [ |
| { |
| "product": "Linux", |
| "vendor": "Linux", |
| "defaultStatus": "unaffected", |
| "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", |
| "programFiles": [ |
| "include/linux/bpf_verifier.h", |
| "kernel/bpf/verifier.c" |
| ], |
| "versions": [ |
| { |
| "version": "51c39bb1d5d105a02e29aa7960f0a395086e6342", |
| "lessThan": "79751e9227a5910c0e5a2c7186877d91821d957d", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "51c39bb1d5d105a02e29aa7960f0a395086e6342", |
| "lessThan": "1d572c60488b52882b719ed273767ee3b280413d", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "51c39bb1d5d105a02e29aa7960f0a395086e6342", |
| "lessThan": "51081a3f25c742da5a659d7fc6fd77ebfdd555be", |
| "status": "affected", |
| "versionType": "git" |
| } |
| ] |
| }, |
| { |
| "product": "Linux", |
| "vendor": "Linux", |
| "defaultStatus": "affected", |
| "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", |
| "programFiles": [ |
| "include/linux/bpf_verifier.h", |
| "kernel/bpf/verifier.c" |
| ], |
| "versions": [ |
| { |
| "version": "5.6", |
| "status": "affected" |
| }, |
| { |
| "version": "0", |
| "lessThan": "5.6", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.6.90", |
| "lessThanOrEqual": "6.6.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.12.25", |
| "lessThanOrEqual": "6.12.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.13", |
| "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": "5.6", |
| "versionEndExcluding": "6.6.90" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "5.6", |
| "versionEndExcluding": "6.12.25" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "5.6", |
| "versionEndExcluding": "6.13" |
| } |
| ] |
| } |
| ] |
| } |
| ], |
| "references": [ |
| { |
| "url": "https://git.kernel.org/stable/c/79751e9227a5910c0e5a2c7186877d91821d957d" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/1d572c60488b52882b719ed273767ee3b280413d" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/51081a3f25c742da5a659d7fc6fd77ebfdd555be" |
| } |
| ], |
| "title": "bpf: track changes_pkt_data property for global functions", |
| "x_generator": { |
| "engine": "bippy-1.2.0" |
| } |
| } |
| }, |
| "cveMetadata": { |
| "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038", |
| "cveID": "CVE-2024-58098", |
| "requesterUserId": "gregkh@kernel.org", |
| "serial": "1", |
| "state": "PUBLISHED" |
| }, |
| "dataType": "CVE_RECORD", |
| "dataVersion": "5.0" |
| } |
