{"api_version":"1","generated_at":"2026-06-02T16:31:47+00:00","cve":"CVE-2025-40257","urls":{"html":"https://cve.report/CVE-2025-40257","api":"https://cve.report/api/cve/CVE-2025-40257.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-40257","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-40257"},"summary":{"title":"mptcp: fix a race in mptcp_pm_del_add_timer()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix a race in mptcp_pm_del_add_timer()\n\nmptcp_pm_del_add_timer() can call sk_stop_timer_sync(sk, &entry->add_timer)\nwhile another might have free entry already, as reported by syzbot.\n\nAdd RCU protection to fix this issue.\n\nAlso change confusing add_timer variable with stop_timer boolean.\n\nsyzbot report:\n\nBUG: KASAN: slab-use-after-free in __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616\nRead of size 4 at addr ffff8880311e4150 by task kworker/1:1/44\n\nCPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025\nWorkqueue: events mptcp_worker\nCall Trace:\n <TASK>\n  dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120\n  print_address_description mm/kasan/report.c:378 [inline]\n  print_report+0xca/0x240 mm/kasan/report.c:482\n  kasan_report+0x118/0x150 mm/kasan/report.c:595\n  __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616\n  sk_stop_timer_sync+0x1b/0x90 net/core/sock.c:3631\n  mptcp_pm_del_add_timer+0x283/0x310 net/mptcp/pm.c:362\n  mptcp_incoming_options+0x1357/0x1f60 net/mptcp/options.c:1174\n  tcp_data_queue+0xca/0x6450 net/ipv4/tcp_input.c:5361\n  tcp_rcv_established+0x1335/0x2670 net/ipv4/tcp_input.c:6441\n  tcp_v4_do_rcv+0x98b/0xbf0 net/ipv4/tcp_ipv4.c:1931\n  tcp_v4_rcv+0x252a/0x2dc0 net/ipv4/tcp_ipv4.c:2374\n  ip_protocol_deliver_rcu+0x221/0x440 net/ipv4/ip_input.c:205\n  ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:239\n  NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318\n  NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318\n  __netif_receive_skb_one_core net/core/dev.c:6079 [inline]\n  __netif_receive_skb+0x143/0x380 net/core/dev.c:6192\n  process_backlog+0x31e/0x900 net/core/dev.c:6544\n  __napi_poll+0xb6/0x540 net/core/dev.c:7594\n  napi_poll net/core/dev.c:7657 [inline]\n  net_rx_action+0x5f7/0xda0 net/core/dev.c:7784\n  handle_softirqs+0x22f/0x710 kernel/softirq.c:622\n  __do_softirq kernel/softirq.c:656 [inline]\n  __local_bh_enable_ip+0x1a0/0x2e0 kernel/softirq.c:302\n  mptcp_pm_send_ack net/mptcp/pm.c:210 [inline]\n mptcp_pm_addr_send_ack+0x41f/0x500 net/mptcp/pm.c:-1\n  mptcp_pm_worker+0x174/0x320 net/mptcp/pm.c:1002\n  mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762\n  process_one_work kernel/workqueue.c:3263 [inline]\n  process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346\n  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427\n  kthread+0x711/0x8a0 kernel/kthread.c:463\n  ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n </TASK>\n\nAllocated by task 44:\n  kasan_save_stack mm/kasan/common.c:56 [inline]\n  kasan_save_track+0x3e/0x80 mm/kasan/common.c:77\n  poison_kmalloc_redzone mm/kasan/common.c:400 [inline]\n  __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417\n  kasan_kmalloc include/linux/kasan.h:262 [inline]\n  __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5748\n  kmalloc_noprof include/linux/slab.h:957 [inline]\n  mptcp_pm_alloc_anno_list+0x104/0x460 net/mptcp/pm.c:385\n  mptcp_pm_create_subflow_or_signal_addr+0xf9d/0x1360 net/mptcp/pm_kernel.c:355\n  mptcp_pm_nl_fully_established net/mptcp/pm_kernel.c:409 [inline]\n  __mptcp_pm_kernel_worker+0x417/0x1ef0 net/mptcp/pm_kernel.c:1529\n  mptcp_pm_worker+0x1ee/0x320 net/mptcp/pm.c:1008\n  mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762\n  process_one_work kernel/workqueue.c:3263 [inline]\n  process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346\n  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427\n  kthread+0x711/0x8a0 kernel/kthread.c:463\n  ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n\nFreed by task 6630:\n  kasan_save_stack mm/kasan/common.c:56 [inline]\n  kasan_save_track+0x3e/0x80 mm/kasan/common.c:77\n  __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587\n  kasan_save_free_info mm/kasan/kasan.h:406 [inline]\n  poison_slab_object m\n---truncated---","state":"PUBLISHED","assigner":"Linux","published_at":"2025-12-04 16:16:19","updated_at":"2026-06-02 14:16:32"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/385ddc0f008f24d1e7d03be998b3a98a37bd29ff","name":"https://git.kernel.org/stable/c/385ddc0f008f24d1e7d03be998b3a98a37bd29ff","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bbbd75346c8e6490b19c2ba90f38ea66ccf352b2","name":"https://git.kernel.org/stable/c/bbbd75346c8e6490b19c2ba90f38ea66ccf352b2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e2d1ad207174a7cd7903dd27a00db4b2dfa6c64b","name":"https://git.kernel.org/stable/c/e2d1ad207174a7cd7903dd27a00db4b2dfa6c64b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-253495.html","name":"https://cert-portal.siemens.com/productcert/html/ssa-253495.html","refsource":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/426358d9be7ce3518966422f87b96f1bad27295f","name":"https://git.kernel.org/stable/c/426358d9be7ce3518966422f87b96f1bad27295f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6d3275d4ca62e2c02e1b7e8cd32db59df91c14b7","name":"https://git.kernel.org/stable/c/6d3275d4ca62e2c02e1b7e8cd32db59df91c14b7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9be29f8e7ce4e147e56caac2c3a0ce3573cf9c17","name":"https://git.kernel.org/stable/c/9be29f8e7ce4e147e56caac2c3a0ce3573cf9c17","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c602cc344b4b8d41515fec3ffa98457ac963ee12","name":"https://git.kernel.org/stable/c/c602cc344b4b8d41515fec3ffa98457ac963ee12","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-40257","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-40257","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 9be29f8e7ce4e147e56caac2c3a0ce3573cf9c17 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 e2d1ad207174a7cd7903dd27a00db4b2dfa6c64b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 385ddc0f008f24d1e7d03be998b3a98a37bd29ff git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 c602cc344b4b8d41515fec3ffa98457ac963ee12 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 6d3275d4ca62e2c02e1b7e8cd32db59df91c14b7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 bbbd75346c8e6490b19c2ba90f38ea66ccf352b2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 00cfd77b9063dcdf3628a7087faba60de85a9cc8 426358d9be7ce3518966422f87b96f1bad27295f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.10","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.247 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.197 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.159 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.118 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.60 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.17.10 6.17.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18 * original_commit_for_fix","platforms":[]},{"source":"ADP","vendor":"Siemens","product":"RUGGEDCOM RST2428P","version":"affected V4.0 custom","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"affected":[{"defaultStatus":"unknown","product":"RUGGEDCOM RST2428P","vendor":"Siemens","versions":[{"lessThan":"V4.0","status":"affected","version":"0","versionType":"custom"}]}],"providerMetadata":{"dateUpdated":"2026-06-02T13:00:10.342Z","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","shortName":"siemens-SADP"},"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-253495.html"}],"x_adpType":"supplier"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/mptcp/pm.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"9be29f8e7ce4e147e56caac2c3a0ce3573cf9c17","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"},{"lessThan":"e2d1ad207174a7cd7903dd27a00db4b2dfa6c64b","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"},{"lessThan":"385ddc0f008f24d1e7d03be998b3a98a37bd29ff","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"},{"lessThan":"c602cc344b4b8d41515fec3ffa98457ac963ee12","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"},{"lessThan":"6d3275d4ca62e2c02e1b7e8cd32db59df91c14b7","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"},{"lessThan":"bbbd75346c8e6490b19c2ba90f38ea66ccf352b2","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"},{"lessThan":"426358d9be7ce3518966422f87b96f1bad27295f","status":"affected","version":"00cfd77b9063dcdf3628a7087faba60de85a9cc8","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/mptcp/pm.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.10"},{"lessThan":"5.10","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.247","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.197","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.159","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.118","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.60","versionType":"semver"},{"lessThanOrEqual":"6.17.*","status":"unaffected","version":"6.17.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.18","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.247","versionStartIncluding":"5.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.197","versionStartIncluding":"5.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.159","versionStartIncluding":"5.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.118","versionStartIncluding":"5.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.60","versionStartIncluding":"5.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.17.10","versionStartIncluding":"5.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18","versionStartIncluding":"5.10","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix a race in mptcp_pm_del_add_timer()\n\nmptcp_pm_del_add_timer() can call sk_stop_timer_sync(sk, &entry->add_timer)\nwhile another might have free entry already, as reported by syzbot.\n\nAdd RCU protection to fix this issue.\n\nAlso change confusing add_timer variable with stop_timer boolean.\n\nsyzbot report:\n\nBUG: KASAN: slab-use-after-free in __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616\nRead of size 4 at addr ffff8880311e4150 by task kworker/1:1/44\n\nCPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025\nWorkqueue: events mptcp_worker\nCall Trace:\n <TASK>\n  dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120\n  print_address_description mm/kasan/report.c:378 [inline]\n  print_report+0xca/0x240 mm/kasan/report.c:482\n  kasan_report+0x118/0x150 mm/kasan/report.c:595\n  __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616\n  sk_stop_timer_sync+0x1b/0x90 net/core/sock.c:3631\n  mptcp_pm_del_add_timer+0x283/0x310 net/mptcp/pm.c:362\n  mptcp_incoming_options+0x1357/0x1f60 net/mptcp/options.c:1174\n  tcp_data_queue+0xca/0x6450 net/ipv4/tcp_input.c:5361\n  tcp_rcv_established+0x1335/0x2670 net/ipv4/tcp_input.c:6441\n  tcp_v4_do_rcv+0x98b/0xbf0 net/ipv4/tcp_ipv4.c:1931\n  tcp_v4_rcv+0x252a/0x2dc0 net/ipv4/tcp_ipv4.c:2374\n  ip_protocol_deliver_rcu+0x221/0x440 net/ipv4/ip_input.c:205\n  ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:239\n  NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318\n  NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318\n  __netif_receive_skb_one_core net/core/dev.c:6079 [inline]\n  __netif_receive_skb+0x143/0x380 net/core/dev.c:6192\n  process_backlog+0x31e/0x900 net/core/dev.c:6544\n  __napi_poll+0xb6/0x540 net/core/dev.c:7594\n  napi_poll net/core/dev.c:7657 [inline]\n  net_rx_action+0x5f7/0xda0 net/core/dev.c:7784\n  handle_softirqs+0x22f/0x710 kernel/softirq.c:622\n  __do_softirq kernel/softirq.c:656 [inline]\n  __local_bh_enable_ip+0x1a0/0x2e0 kernel/softirq.c:302\n  mptcp_pm_send_ack net/mptcp/pm.c:210 [inline]\n mptcp_pm_addr_send_ack+0x41f/0x500 net/mptcp/pm.c:-1\n  mptcp_pm_worker+0x174/0x320 net/mptcp/pm.c:1002\n  mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762\n  process_one_work kernel/workqueue.c:3263 [inline]\n  process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346\n  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427\n  kthread+0x711/0x8a0 kernel/kthread.c:463\n  ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n </TASK>\n\nAllocated by task 44:\n  kasan_save_stack mm/kasan/common.c:56 [inline]\n  kasan_save_track+0x3e/0x80 mm/kasan/common.c:77\n  poison_kmalloc_redzone mm/kasan/common.c:400 [inline]\n  __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417\n  kasan_kmalloc include/linux/kasan.h:262 [inline]\n  __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5748\n  kmalloc_noprof include/linux/slab.h:957 [inline]\n  mptcp_pm_alloc_anno_list+0x104/0x460 net/mptcp/pm.c:385\n  mptcp_pm_create_subflow_or_signal_addr+0xf9d/0x1360 net/mptcp/pm_kernel.c:355\n  mptcp_pm_nl_fully_established net/mptcp/pm_kernel.c:409 [inline]\n  __mptcp_pm_kernel_worker+0x417/0x1ef0 net/mptcp/pm_kernel.c:1529\n  mptcp_pm_worker+0x1ee/0x320 net/mptcp/pm.c:1008\n  mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762\n  process_one_work kernel/workqueue.c:3263 [inline]\n  process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346\n  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427\n  kthread+0x711/0x8a0 kernel/kthread.c:463\n  ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n\nFreed by task 6630:\n  kasan_save_stack mm/kasan/common.c:56 [inline]\n  kasan_save_track+0x3e/0x80 mm/kasan/common.c:77\n  __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587\n  kasan_save_free_info mm/kasan/kasan.h:406 [inline]\n  poison_slab_object m\n---truncated---"}],"providerMetadata":{"dateUpdated":"2026-05-11T21:45:50.143Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/9be29f8e7ce4e147e56caac2c3a0ce3573cf9c17"},{"url":"https://git.kernel.org/stable/c/e2d1ad207174a7cd7903dd27a00db4b2dfa6c64b"},{"url":"https://git.kernel.org/stable/c/385ddc0f008f24d1e7d03be998b3a98a37bd29ff"},{"url":"https://git.kernel.org/stable/c/c602cc344b4b8d41515fec3ffa98457ac963ee12"},{"url":"https://git.kernel.org/stable/c/6d3275d4ca62e2c02e1b7e8cd32db59df91c14b7"},{"url":"https://git.kernel.org/stable/c/bbbd75346c8e6490b19c2ba90f38ea66ccf352b2"},{"url":"https://git.kernel.org/stable/c/426358d9be7ce3518966422f87b96f1bad27295f"}],"title":"mptcp: fix a race in mptcp_pm_del_add_timer()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2025-40257","datePublished":"2025-12-04T16:08:18.433Z","dateReserved":"2025-04-16T07:20:57.182Z","dateUpdated":"2026-06-02T13:00:10.342Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-12-04 16:16:19","lastModifiedDate":"2026-06-02 14:16:32","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2025","CveId":"40257","Ordinal":"1","Title":"mptcp: fix a race in mptcp_pm_del_add_timer()","CVE":"CVE-2025-40257","Year":"2025"},"notes":[{"CveYear":"2025","CveId":"40257","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix a race in mptcp_pm_del_add_timer()\n\nmptcp_pm_del_add_timer() can call sk_stop_timer_sync(sk, &entry->add_timer)\nwhile another might have free entry already, as reported by syzbot.\n\nAdd RCU protection to fix this issue.\n\nAlso change confusing add_timer variable with stop_timer boolean.\n\nsyzbot report:\n\nBUG: KASAN: slab-use-after-free in __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616\nRead of size 4 at addr ffff8880311e4150 by task kworker/1:1/44\n\nCPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025\nWorkqueue: events mptcp_worker\nCall Trace:\n <TASK>\n  dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120\n  print_address_description mm/kasan/report.c:378 [inline]\n  print_report+0xca/0x240 mm/kasan/report.c:482\n  kasan_report+0x118/0x150 mm/kasan/report.c:595\n  __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616\n  sk_stop_timer_sync+0x1b/0x90 net/core/sock.c:3631\n  mptcp_pm_del_add_timer+0x283/0x310 net/mptcp/pm.c:362\n  mptcp_incoming_options+0x1357/0x1f60 net/mptcp/options.c:1174\n  tcp_data_queue+0xca/0x6450 net/ipv4/tcp_input.c:5361\n  tcp_rcv_established+0x1335/0x2670 net/ipv4/tcp_input.c:6441\n  tcp_v4_do_rcv+0x98b/0xbf0 net/ipv4/tcp_ipv4.c:1931\n  tcp_v4_rcv+0x252a/0x2dc0 net/ipv4/tcp_ipv4.c:2374\n  ip_protocol_deliver_rcu+0x221/0x440 net/ipv4/ip_input.c:205\n  ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:239\n  NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318\n  NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318\n  __netif_receive_skb_one_core net/core/dev.c:6079 [inline]\n  __netif_receive_skb+0x143/0x380 net/core/dev.c:6192\n  process_backlog+0x31e/0x900 net/core/dev.c:6544\n  __napi_poll+0xb6/0x540 net/core/dev.c:7594\n  napi_poll net/core/dev.c:7657 [inline]\n  net_rx_action+0x5f7/0xda0 net/core/dev.c:7784\n  handle_softirqs+0x22f/0x710 kernel/softirq.c:622\n  __do_softirq kernel/softirq.c:656 [inline]\n  __local_bh_enable_ip+0x1a0/0x2e0 kernel/softirq.c:302\n  mptcp_pm_send_ack net/mptcp/pm.c:210 [inline]\n mptcp_pm_addr_send_ack+0x41f/0x500 net/mptcp/pm.c:-1\n  mptcp_pm_worker+0x174/0x320 net/mptcp/pm.c:1002\n  mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762\n  process_one_work kernel/workqueue.c:3263 [inline]\n  process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346\n  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427\n  kthread+0x711/0x8a0 kernel/kthread.c:463\n  ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n </TASK>\n\nAllocated by task 44:\n  kasan_save_stack mm/kasan/common.c:56 [inline]\n  kasan_save_track+0x3e/0x80 mm/kasan/common.c:77\n  poison_kmalloc_redzone mm/kasan/common.c:400 [inline]\n  __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417\n  kasan_kmalloc include/linux/kasan.h:262 [inline]\n  __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5748\n  kmalloc_noprof include/linux/slab.h:957 [inline]\n  mptcp_pm_alloc_anno_list+0x104/0x460 net/mptcp/pm.c:385\n  mptcp_pm_create_subflow_or_signal_addr+0xf9d/0x1360 net/mptcp/pm_kernel.c:355\n  mptcp_pm_nl_fully_established net/mptcp/pm_kernel.c:409 [inline]\n  __mptcp_pm_kernel_worker+0x417/0x1ef0 net/mptcp/pm_kernel.c:1529\n  mptcp_pm_worker+0x1ee/0x320 net/mptcp/pm.c:1008\n  mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762\n  process_one_work kernel/workqueue.c:3263 [inline]\n  process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346\n  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427\n  kthread+0x711/0x8a0 kernel/kthread.c:463\n  ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n\nFreed by task 6630:\n  kasan_save_stack mm/kasan/common.c:56 [inline]\n  kasan_save_track+0x3e/0x80 mm/kasan/common.c:77\n  __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587\n  kasan_save_free_info mm/kasan/kasan.h:406 [inline]\n  poison_slab_object m\n---truncated---","Type":"Description","Title":"mptcp: fix a race in mptcp_pm_del_add_timer()"}]}}}