{"id":"CVE-2024-35934","state":"PUBLISHED","title":"net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list()\n\nMany syzbot reports show extreme rtnl pressure, and many of them hint\nthat smc acquires rtnl in netns creation for no good reason [1]\n\nThis patch returns early from smc_pnet_net_init()\nif there is no netdevice yet.\n\nI am not even sure why smc_pnet_create_pnetids_list() even exists,\nbecause smc_pnet_netdev_event() is also calling\nsmc_pnet_add_base_pnetid() when handling NETDEV_UP event.\n\n[1] extract of typical syzbot reports\n\n2 locks held by syz-executor.3/12252:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.4/12253:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.1/12257:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.2/12261:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.0/12265:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.3/12268:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.4/12271:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.1/12274:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.2/12280:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878","publishedAt":"2024-05-19T10:10:41.668Z","updatedAt":"2026-10-15T00:41:32.527Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"bc4d1ebca11b4f194e262326bd45938e857c59d2","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"b9117dc783c0ab0a3866812f70e07bf2ea071ac4","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"a2e6bffc0388526ed10406040279a693d62b36ec","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"6e920422e7104928f760fc0e12b6d65ab097a2e7","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"00af2aa93b76b1bade471ad0d0525d4d29ca5cc0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_pnet.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.10","versionType":"semver"},{"version":"5.10.215","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.155","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.86","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.27","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.8.6","status":"unaffected","lessThanOrEqual":"6.8.*","versionType":"semver"},{"version":"6.9","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_pnet.c"]}],"references":["https://git.kernel.org/stable/c/bc4d1ebca11b4f194e262326bd45938e857c59d2","https://git.kernel.org/stable/c/b9117dc783c0ab0a3866812f70e07bf2ea071ac4","https://git.kernel.org/stable/c/d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23","https://git.kernel.org/stable/c/a2e6bffc0388526ed10406040279a693d62b36ec","https://git.kernel.org/stable/c/6e920422e7104928f760fc0e12b6d65ab097a2e7","https://git.kernel.org/stable/c/00af2aa93b76b1bade471ad0d0525d4d29ca5cc0","https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html","https://cert-portal.siemens.com/productcert/html/ssa-265688.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:07:30.303Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/35xxx/CVE-2024-35934.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-35934","state":"PUBLISHED","datePublished":"2024-05-19T10:10:41.668Z","dateUpdated":"2026-10-15T00:41:32.527Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-05-17T13:50:33.130Z"},"containers":{"cna":{"title":"net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list()\n\nMany syzbot reports show extreme rtnl pressure, and many of them hint\nthat smc acquires rtnl in netns creation for no good reason [1]\n\nThis patch returns early from smc_pnet_net_init()\nif there is no netdevice yet.\n\nI am not even sure why smc_pnet_create_pnetids_list() even exists,\nbecause smc_pnet_netdev_event() is also calling\nsmc_pnet_add_base_pnetid() when handling NETDEV_UP event.\n\n[1] extract of typical syzbot reports\n\n2 locks held by syz-executor.3/12252:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.4/12253:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.1/12257:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.2/12261:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.0/12265:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.3/12268:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.4/12271:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.1/12274:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878\n2 locks held by syz-executor.2/12280:\n  #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline]\n  #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"bc4d1ebca11b4f194e262326bd45938e857c59d2","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"b9117dc783c0ab0a3866812f70e07bf2ea071ac4","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"a2e6bffc0388526ed10406040279a693d62b36ec","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"6e920422e7104928f760fc0e12b6d65ab097a2e7","versionType":"git"},{"version":"e888a2e8337c96dd785d204cf8ff775e79173add","status":"affected","lessThan":"00af2aa93b76b1bade471ad0d0525d4d29ca5cc0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_pnet.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.10","versionType":"semver"},{"version":"5.10.215","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.155","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.86","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.27","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.8.6","status":"unaffected","lessThanOrEqual":"6.8.*","versionType":"semver"},{"version":"6.9","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_pnet.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/bc4d1ebca11b4f194e262326bd45938e857c59d2"},{"url":"https://git.kernel.org/stable/c/b9117dc783c0ab0a3866812f70e07bf2ea071ac4"},{"url":"https://git.kernel.org/stable/c/d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23"},{"url":"https://git.kernel.org/stable/c/a2e6bffc0388526ed10406040279a693d62b36ec"},{"url":"https://git.kernel.org/stable/c/6e920422e7104928f760fc0e12b6d65ab097a2e7"},{"url":"https://git.kernel.org/stable/c/00af2aa93b76b1bade471ad0d0525d4d29ca5cc0"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T20:14:00.958Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"5.10.215"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"5.15.155"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.1.86"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.6.27"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.8.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.9"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE 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Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2024-35934","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-09-10T15:40:58.599297Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-09-11T17:33:15.404Z"}},{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"V1.1.1","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T00:41:32.527Z"},"x_adpType":"supplier"}]}}}