{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98103", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.315Z", "datePublished": "2026-09-25T10:35:53.942Z", "dateUpdated": "2026-10-21T12:54:31.184Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:54:31.184Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nigmp: convert struct ip_sf_list to RCU\n\nCommit 23d2b94043ca (\"igmp: Add ip_mc_list lock in ip_check_mc_rcu\")\nadded spin_lock_bh(&im->lock) to ip_check_mc_rcu() to prevent a\nuse-after-free while iterating im->sources during concurrent deletions.\n\nHowever, ip_check_mc_rcu() is called from RCU read-side critical\nsections in packet receive and route lookup fast paths (e.g.\n__mkroute_output(), ip_route_input_rcu(), and __udp4_lib_rcv()).\n\nWhen igmpv3_send_cr() or igmpv3_send_report() holds &pmc->lock and\ncalls add_grec() -> igmpv3_newpack() -> ip_route_output_ports(),\nan XFRM policy matching a multicast destination triggers\nxfrm_tmpl_resolve_one() -> xfrm4_get_saddr() -> __mkroute_output() ->\nip_check_mc_rcu(). This attempts to acquire &im->lock while &pmc->lock\nis already held on the same CPU, triggering a lockdep recursive locking\nwarning / deadlock.\n\nFix this by converting IPv4 struct ip_sf_list to RCU, mirroring the\nIPv6 implementation in net/ipv6/mcast.c:\n\n1. Add struct rcu_head to struct ip_sf_list and annotate sf_next,\n sources, and tomb as __rcu pointers.\n2. Use rcu_assign_pointer() and kfree_rcu() for list updates and\n deletions.\n3. Remove spin_lock_bh(&im->lock) from ip_check_mc_rcu() and traverse\n im->sources locklessly with for_each_psf_rcu(), reading and writing\n counter fields with READ_ONCE() and WRITE_ONCE().\n\nNote: RCU conversion of /proc/net/mcfilter will be done in a\nseparate patch." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/linux/igmp.h", "net/ipv4/igmp.c" ], "versions": [ { "version": "23d2b94043ca8835bd1e67749020e839f396a1c2", "lessThan": "01131daffc4b64f1652e23dc3e6e2f601eda781d", "status": "affected", "versionType": "git" }, { "version": "23d2b94043ca8835bd1e67749020e839f396a1c2", "lessThan": "f5182dfad54277267a8cb0c004a9cd4cf35aeebb", "status": "affected", "versionType": "git" }, { "version": "23d2b94043ca8835bd1e67749020e839f396a1c2", "lessThan": "d3011d1f293478c730aa0870490afa145c37600e", "status": "affected", "versionType": "git" }, { "version": "23d2b94043ca8835bd1e67749020e839f396a1c2", "lessThan": "e3206419bdb04e2087d8cc6be324df8639b3fac5", "status": "affected", "versionType": "git" }, { "version": "23d2b94043ca8835bd1e67749020e839f396a1c2", "lessThan": "2987ee196c88dbde0463dc87d5fb209c684e34a2", "status": "affected", "versionType": "git" }, { "version": "b24065948ae6c48c9e20891f8cfe9850f1d748be", "status": "affected", "versionType": "git" }, { "version": "e9924c4204ede999b0515fd31a370a1e27f676bc", "status": "affected", "versionType": "git" }, { "version": "78967749984cf3614de346c90f3e259ff8272735", "status": "affected", "versionType": "git" }, { "version": "4768973dffed4d0126854514335ed4fe87bec1ab", "status": "affected", "versionType": "git" }, { "version": "d84708451d9041dff8a81e3718f821f12d2eb6c5", "status": "affected", "versionType": "git" }, { "version": "ddd7e8b7b84836c584a284b98ca9bd7a348a0558", "status": "affected", "versionType": "git" }, { "version": "961447ff60291b91e27d5c32fa549c1411ad3b70", "status": "affected", "versionType": "git" }, { "version": "d1a3c6d5925a8d00a32c5ef2d674dd9c0ce89c95", "status": "affected", "versionType": "git" }, { "version": "4.4.284", "lessThan": "4.5", "status": "affected", "versionType": "semver" }, { "version": "4.9.283", "lessThan": "4.10", "status": "affected", "versionType": "semver" }, { "version": "4.14.247", "lessThan": "4.15", "status": "affected", "versionType": "semver" }, { "version": "4.19.207", "lessThan": "4.20", "status": "affected", "versionType": "semver" }, { "version": "5.4.145", "lessThan": "5.5", "status": "affected", "versionType": "semver" }, { "version": "5.10.64", "lessThan": "5.11", "status": "affected", "versionType": "semver" }, { "version": "5.13.16", "lessThan": "5.14", "status": "affected", "versionType": "semver" }, { "version": "5.14.3", "lessThan": "5.15", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/linux/igmp.h", "net/ipv4/igmp.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.7", "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": "5.15", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.111" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.53" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.2.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4.284" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.9.283" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14.247" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19.207" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.64" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/01131daffc4b64f1652e23dc3e6e2f601eda781d" }, { "url": "https://git.kernel.org/stable/c/f5182dfad54277267a8cb0c004a9cd4cf35aeebb" }, { "url": "https://git.kernel.org/stable/c/d3011d1f293478c730aa0870490afa145c37600e" }, { "url": "https://git.kernel.org/stable/c/e3206419bdb04e2087d8cc6be324df8639b3fac5" }, { "url": "https://git.kernel.org/stable/c/2987ee196c88dbde0463dc87d5fb209c684e34a2" } ], "title": "igmp: convert struct ip_sf_list to RCU", "x_generator": { "engine": "bippy-1.2.0" } } } }