{"id":"CVE-2025-21862","state":"PUBLISHED","title":"drop_monitor: fix incorrect initialization order","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrop_monitor: fix incorrect initialization order\n\nSyzkaller reports the following bug:\n\nBUG: spinlock bad magic on CPU#1, syz-executor.0/7995\n lock: 0xffff88805303f3e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0\nCPU: 1 PID: 7995 Comm: syz-executor.0 Tainted: G            E     5.10.209+ #1\nHardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020\nCall Trace:\n __dump_stack lib/dump_stack.c:77 [inline]\n dump_stack+0x119/0x179 lib/dump_stack.c:118\n debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]\n do_raw_spin_lock+0x1f6/0x270 kernel/locking/spinlock_debug.c:112\n __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]\n _raw_spin_lock_irqsave+0x50/0x70 kernel/locking/spinlock.c:159\n reset_per_cpu_data+0xe6/0x240 [drop_monitor]\n net_dm_cmd_trace+0x43d/0x17a0 [drop_monitor]\n genl_family_rcv_msg_doit+0x22f/0x330 net/netlink/genetlink.c:739\n genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]\n genl_rcv_msg+0x341/0x5a0 net/netlink/genetlink.c:800\n netlink_rcv_skb+0x14d/0x440 net/netlink/af_netlink.c:2497\n genl_rcv+0x29/0x40 net/netlink/genetlink.c:811\n netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]\n netlink_unicast+0x54b/0x800 net/netlink/af_netlink.c:1348\n netlink_sendmsg+0x914/0xe00 net/netlink/af_netlink.c:1916\n sock_sendmsg_nosec net/socket.c:651 [inline]\n __sock_sendmsg+0x157/0x190 net/socket.c:663\n ____sys_sendmsg+0x712/0x870 net/socket.c:2378\n ___sys_sendmsg+0xf8/0x170 net/socket.c:2432\n __sys_sendmsg+0xea/0x1b0 net/socket.c:2461\n do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46\n entry_SYSCALL_64_after_hwframe+0x62/0xc7\nRIP: 0033:0x7f3f9815aee9\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007f3f972bf0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\nRAX: ffffffffffffffda RBX: 00007f3f9826d050 RCX: 00007f3f9815aee9\nRDX: 0000000020000000 RSI: 0000000020001300 RDI: 0000000000000007\nRBP: 00007f3f981b63bd R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 000000000000006e R14: 00007f3f9826d050 R15: 00007ffe01ee6768\n\nIf drop_monitor is built as a kernel module, syzkaller may have time\nto send a netlink NET_DM_CMD_START message during the module loading.\nThis will call the net_dm_monitor_start() function that uses\na spinlock that has not yet been initialized.\n\nTo fix this, let's place resource initialization above the registration\nof a generic netlink family.\n\nFound by InfoTeCS on behalf of Linux Verification Center\n(linuxtesting.org) with Syzkaller.","publishedAt":"2025-03-12T09:42:19.881Z","updatedAt":"2026-10-15T01:04:52.887Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"6e9e0f224ffd8b819da3ea247dda404795fdd182","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"29f9cdcab3d96d5207a5c92b52c40ad75e5915d8","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"872c7c7e57a746046796ddfead529c9d37b9f6b4","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"fcfc00bfec7bb6661074cb21356d05a4c9470a3c","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"0efa6c42f81c60d8f72ba7f5ed8d4fec8c526282","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"b7859e8643e75619b2705b4fcac93ffd94d72b4a","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"219a47d0e6195bd202f22855e35f25bd15bc4d58","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"07b598c0e6f06a0f254c88dafb4ad50f8a8c6eea","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/drop_monitor.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.30","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.30","versionType":"semver"},{"version":"5.4.291","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.235","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.179","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.130","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.80","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.17","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13.5","status":"unaffected","lessThanOrEqual":"6.13.*","versionType":"semver"},{"version":"6.14","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/drop_monitor.c"]}],"references":["https://git.kernel.org/stable/c/6e9e0f224ffd8b819da3ea247dda404795fdd182","https://git.kernel.org/stable/c/29f9cdcab3d96d5207a5c92b52c40ad75e5915d8","https://git.kernel.org/stable/c/872c7c7e57a746046796ddfead529c9d37b9f6b4","https://git.kernel.org/stable/c/fcfc00bfec7bb6661074cb21356d05a4c9470a3c","https://git.kernel.org/stable/c/0efa6c42f81c60d8f72ba7f5ed8d4fec8c526282","https://git.kernel.org/stable/c/b7859e8643e75619b2705b4fcac93ffd94d72b4a","https://git.kernel.org/stable/c/219a47d0e6195bd202f22855e35f25bd15bc4d58","https://git.kernel.org/stable/c/07b598c0e6f06a0f254c88dafb4ad50f8a8c6eea","https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html","https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html","https://cert-portal.siemens.com/productcert/html/ssa-265688.html","https://cert-portal.siemens.com/productcert/html/ssa-082556.html","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-908"],"ingestedAt":"2026-10-29T20:08:39.238Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/21xxx/CVE-2025-21862.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-21862","state":"PUBLISHED","datePublished":"2025-03-12T09:42:19.881Z","dateUpdated":"2026-10-15T01:04:52.887Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-12-29T08:45:45.780Z"},"containers":{"cna":{"title":"drop_monitor: fix incorrect initialization order","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrop_monitor: fix incorrect initialization order\n\nSyzkaller reports the following bug:\n\nBUG: spinlock bad magic on CPU#1, syz-executor.0/7995\n lock: 0xffff88805303f3e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0\nCPU: 1 PID: 7995 Comm: syz-executor.0 Tainted: G            E     5.10.209+ #1\nHardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020\nCall Trace:\n __dump_stack lib/dump_stack.c:77 [inline]\n dump_stack+0x119/0x179 lib/dump_stack.c:118\n debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]\n do_raw_spin_lock+0x1f6/0x270 kernel/locking/spinlock_debug.c:112\n __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]\n _raw_spin_lock_irqsave+0x50/0x70 kernel/locking/spinlock.c:159\n reset_per_cpu_data+0xe6/0x240 [drop_monitor]\n net_dm_cmd_trace+0x43d/0x17a0 [drop_monitor]\n genl_family_rcv_msg_doit+0x22f/0x330 net/netlink/genetlink.c:739\n genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]\n genl_rcv_msg+0x341/0x5a0 net/netlink/genetlink.c:800\n netlink_rcv_skb+0x14d/0x440 net/netlink/af_netlink.c:2497\n genl_rcv+0x29/0x40 net/netlink/genetlink.c:811\n netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]\n netlink_unicast+0x54b/0x800 net/netlink/af_netlink.c:1348\n netlink_sendmsg+0x914/0xe00 net/netlink/af_netlink.c:1916\n sock_sendmsg_nosec net/socket.c:651 [inline]\n __sock_sendmsg+0x157/0x190 net/socket.c:663\n ____sys_sendmsg+0x712/0x870 net/socket.c:2378\n ___sys_sendmsg+0xf8/0x170 net/socket.c:2432\n __sys_sendmsg+0xea/0x1b0 net/socket.c:2461\n do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46\n entry_SYSCALL_64_after_hwframe+0x62/0xc7\nRIP: 0033:0x7f3f9815aee9\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007f3f972bf0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\nRAX: ffffffffffffffda RBX: 00007f3f9826d050 RCX: 00007f3f9815aee9\nRDX: 0000000020000000 RSI: 0000000020001300 RDI: 0000000000000007\nRBP: 00007f3f981b63bd R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 000000000000006e R14: 00007f3f9826d050 R15: 00007ffe01ee6768\n\nIf drop_monitor is built as a kernel module, syzkaller may have time\nto send a netlink NET_DM_CMD_START message during the module loading.\nThis will call the net_dm_monitor_start() function that uses\na spinlock that has not yet been initialized.\n\nTo fix this, let's place resource initialization above the registration\nof a generic netlink family.\n\nFound by InfoTeCS on behalf of Linux Verification Center\n(linuxtesting.org) with Syzkaller."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"6e9e0f224ffd8b819da3ea247dda404795fdd182","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"29f9cdcab3d96d5207a5c92b52c40ad75e5915d8","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"872c7c7e57a746046796ddfead529c9d37b9f6b4","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"fcfc00bfec7bb6661074cb21356d05a4c9470a3c","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"0efa6c42f81c60d8f72ba7f5ed8d4fec8c526282","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"b7859e8643e75619b2705b4fcac93ffd94d72b4a","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"219a47d0e6195bd202f22855e35f25bd15bc4d58","versionType":"git"},{"version":"9a8afc8d3962f3ed26fd6b56db34133860ed1e72","status":"affected","lessThan":"07b598c0e6f06a0f254c88dafb4ad50f8a8c6eea","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/drop_monitor.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.30","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.30","versionType":"semver"},{"version":"5.4.291","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.235","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.179","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.130","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.80","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.17","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13.5","status":"unaffected","lessThanOrEqual":"6.13.*","versionType":"semver"},{"version":"6.14","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/drop_monitor.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/6e9e0f224ffd8b819da3ea247dda404795fdd182"},{"url":"https://git.kernel.org/stable/c/29f9cdcab3d96d5207a5c92b52c40ad75e5915d8"},{"url":"https://git.kernel.org/stable/c/872c7c7e57a746046796ddfead529c9d37b9f6b4"},{"url":"https://git.kernel.org/stable/c/fcfc00bfec7bb6661074cb21356d05a4c9470a3c"},{"url":"https://git.kernel.org/stable/c/0efa6c42f81c60d8f72ba7f5ed8d4fec8c526282"},{"url":"https://git.kernel.org/stable/c/b7859e8643e75619b2705b4fcac93ffd94d72b4a"},{"url":"https://git.kernel.org/stable/c/219a47d0e6195bd202f22855e35f25bd15bc4d58"},{"url":"https://git.kernel.org/stable/c/07b598c0e6f06a0f254c88dafb4ad50f8a8c6eea"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:07:56.958Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"5.4.291"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"5.10.235"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"5.15.179"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.1.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.6.80"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.12.17"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.13.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.14"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2025-21862","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:25:42.627398Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-908","lang":"en","type":"CWE","description":"CWE-908 Use of Uninitialized Resource"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:26:37.640Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-03T19:38:19.222Z"}},{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIPLUS S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:04:52.887Z"},"x_adpType":"supplier"}]}}}