{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-04-22T05:17:13.692","vulnerabilities":[{"cve":{"id":"CVE-2021-47402","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2024-05-21T15:15:25.690","lastModified":"2025-01-14T17:29:04.687","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: flower: protect fl_walk() with rcu\n\nPatch that refactored fl_walk() to use idr_for_each_entry_continue_ul()\nalso removed rcu protection of individual filters which causes following\nuse-after-free when filter is deleted concurrently. Fix fl_walk() to obtain\nrcu read lock while iterating and taking the filter reference and temporary\nrelease the lock while calling arg->fn() callback that can sleep.\n\nKASAN trace:\n\n[  352.773640] ==================================================================\n[  352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower]\n[  352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987\n\n[  352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2\n[  352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[  352.781022] Call Trace:\n[  352.781573]  dump_stack_lvl+0x46/0x5a\n[  352.782332]  print_address_description.constprop.0+0x1f/0x140\n[  352.783400]  ? fl_walk+0x159/0x240 [cls_flower]\n[  352.784292]  ? fl_walk+0x159/0x240 [cls_flower]\n[  352.785138]  kasan_report.cold+0x83/0xdf\n[  352.785851]  ? fl_walk+0x159/0x240 [cls_flower]\n[  352.786587]  kasan_check_range+0x145/0x1a0\n[  352.787337]  fl_walk+0x159/0x240 [cls_flower]\n[  352.788163]  ? fl_put+0x10/0x10 [cls_flower]\n[  352.789007]  ? __mutex_unlock_slowpath.constprop.0+0x220/0x220\n[  352.790102]  tcf_chain_dump+0x231/0x450\n[  352.790878]  ? tcf_chain_tp_delete_empty+0x170/0x170\n[  352.791833]  ? __might_sleep+0x2e/0xc0\n[  352.792594]  ? tfilter_notify+0x170/0x170\n[  352.793400]  ? __mutex_unlock_slowpath.constprop.0+0x220/0x220\n[  352.794477]  tc_dump_tfilter+0x385/0x4b0\n[  352.795262]  ? tc_new_tfilter+0x1180/0x1180\n[  352.796103]  ? __mod_node_page_state+0x1f/0xc0\n[  352.796974]  ? __build_skb_around+0x10e/0x130\n[  352.797826]  netlink_dump+0x2c0/0x560\n[  352.798563]  ? netlink_getsockopt+0x430/0x430\n[  352.799433]  ? __mutex_unlock_slowpath.constprop.0+0x220/0x220\n[  352.800542]  __netlink_dump_start+0x356/0x440\n[  352.801397]  rtnetlink_rcv_msg+0x3ff/0x550\n[  352.802190]  ? tc_new_tfilter+0x1180/0x1180\n[  352.802872]  ? rtnl_calcit.isra.0+0x1f0/0x1f0\n[  352.803668]  ? tc_new_tfilter+0x1180/0x1180\n[  352.804344]  ? _copy_from_iter_nocache+0x800/0x800\n[  352.805202]  ? kasan_set_track+0x1c/0x30\n[  352.805900]  netlink_rcv_skb+0xc6/0x1f0\n[  352.806587]  ? rht_deferred_worker+0x6b0/0x6b0\n[  352.807455]  ? rtnl_calcit.isra.0+0x1f0/0x1f0\n[  352.808324]  ? netlink_ack+0x4d0/0x4d0\n[  352.809086]  ? netlink_deliver_tap+0x62/0x3d0\n[  352.809951]  netlink_unicast+0x353/0x480\n[  352.810744]  ? netlink_attachskb+0x430/0x430\n[  352.811586]  ? __alloc_skb+0xd7/0x200\n[  352.812349]  netlink_sendmsg+0x396/0x680\n[  352.813132]  ? netlink_unicast+0x480/0x480\n[  352.813952]  ? __import_iovec+0x192/0x210\n[  352.814759]  ? netlink_unicast+0x480/0x480\n[  352.815580]  sock_sendmsg+0x6c/0x80\n[  352.816299]  ____sys_sendmsg+0x3a5/0x3c0\n[  352.817096]  ? kernel_sendmsg+0x30/0x30\n[  352.817873]  ? __ia32_sys_recvmmsg+0x150/0x150\n[  352.818753]  ___sys_sendmsg+0xd8/0x140\n[  352.819518]  ? sendmsg_copy_msghdr+0x110/0x110\n[  352.820402]  ? ___sys_recvmsg+0xf4/0x1a0\n[  352.821110]  ? __copy_msghdr_from_user+0x260/0x260\n[  352.821934]  ? _raw_spin_lock+0x81/0xd0\n[  352.822680]  ? __handle_mm_fault+0xef3/0x1b20\n[  352.823549]  ? rb_insert_color+0x2a/0x270\n[  352.824373]  ? copy_page_range+0x16b0/0x16b0\n[  352.825209]  ? perf_event_update_userpage+0x2d0/0x2d0\n[  352.826190]  ? __fget_light+0xd9/0xf0\n[  352.826941]  __sys_sendmsg+0xb3/0x130\n[  352.827613]  ? __sys_sendmsg_sock+0x20/0x20\n[  352.828377]  ? do_user_addr_fault+0x2c5/0x8a0\n[  352.829184]  ? fpregs_assert_state_consistent+0x52/0x60\n[  352.830001]  ? exit_to_user_mode_prepare+0x32/0x160\n[  352.830845]  do_syscall_64+0x35/0x80\n[  352.831445]  entry_SYSCALL_64_after_hwframe+0x44/0xae\n[  352.832331] RIP: 0033:0x7f7bee973c17\n[ \n---truncated---"},{"lang":"es","value":"En el kernel de Linux, se resolvió la siguiente vulnerabilidad: net: sched: flower: protege fl_walk() con rcu. El parche que refactorizó fl_walk() para usar idr_for_each_entry_continue_ul() también eliminó la protección de rcu de filtros individuales que provoca el siguiente use after free. cuando el filtro se elimina simultáneamente. Se corrige fl_walk() para obtener el bloqueo de lectura de rcu mientras se itera y se toma la referencia del filtro y se libera temporalmente el bloqueo mientras se llama a la devolución de llamada arg->fn() que puede dormir. Seguimiento de KASAN: [352.773640] ============================================= ========================== [352.775041] ERROR: KASAN: use-after-free en fl_walk+0x159/0x240 [cls_flower] [352.776304] Lectura de tamaño 4 en addr ffff8881c8251480 por tarea tc/2987 [ 352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2 [ 352.778980] Nombre de hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13 .0-0-gf21b5a4aeb02-prebuilt.qemu.org 01/04/2014 [352.781022] Seguimiento de llamadas: [352.781573] dump_stack_lvl+0x46/0x5a [352.782332] print_address_description.constprop.0+0x1f/0x140 [ 352.783400] ? fl_walk+0x159/0x240 [cls_flower] [ 352.784292] ? fl_walk+0x159/0x240 [cls_flower] [ 352.785138] kasan_report.cold+0x83/0xdf [ 352.785851] ? fl_walk+0x159/0x240 [cls_flower] [ 352.786587] kasan_check_range+0x145/0x1a0 [ 352.787337] fl_walk+0x159/0x240 [cls_flower] [ 352.788163] ? fl_put+0x10/0x10 [cls_flower] [ 352.789007] ? __mutex_unlock_slowpath.constprop.0+0x220/0x220 [352.790102] tcf_chain_dump+0x231/0x450 [352.790878]? tcf_chain_tp_delete_empty+0x170/0x170 [352.791833]? __might_sleep+0x2e/0xc0 [ 352.792594] ? tfilter_notify+0x170/0x170 [352.793400]? __mutex_unlock_slowpath.constprop.0+0x220/0x220 [352.794477] tc_dump_tfilter+0x385/0x4b0 [352.795262]? tc_new_tfilter+0x1180/0x1180 [352.796103]? __mod_node_page_state+0x1f/0xc0 [352.796974]? __build_skb_around+0x10e/0x130 [ 352.797826] netlink_dump+0x2c0/0x560 [ 352.798563] ? netlink_getsockopt+0x430/0x430 [352.799433]? __mutex_unlock_slowpath.constprop.0+0x220/0x220 [ 352.800542] __netlink_dump_start+0x356/0x440 [ 352.801397] rtnetlink_rcv_msg+0x3ff/0x550 [ 352.802190] ? tc_new_tfilter+0x1180/0x1180 [352.802872]? rtnl_calcit.isra.0+0x1f0/0x1f0 [ 352.803668] ? tc_new_tfilter+0x1180/0x1180 [352.804344]? _copy_from_iter_nocache+0x800/0x800 [352.805202]? kasan_set_track+0x1c/0x30 [ 352.805900] netlink_rcv_skb+0xc6/0x1f0 [ 352.806587] ? rht_deferred_worker+0x6b0/0x6b0 [352.807455]? rtnl_calcit.isra.0+0x1f0/0x1f0 [352.808324]? netlink_ack+0x4d0/0x4d0 [352.809086]? netlink_deliver_tap+0x62/0x3d0 [352.809951] netlink_unicast+0x353/0x480 [352.810744]? netlink_attachskb+0x430/0x430 [352.811586]? __alloc_skb+0xd7/0x200 [ 352.812349] netlink_sendmsg+0x396/0x680 [ 352.813132] ? netlink_unicast+0x480/0x480 [352.813952]? __import_iovec+0x192/0x210 [352.814759]? netlink_unicast+0x480/0x480 [352.815580] sock_sendmsg+0x6c/0x80 [352.816299] ____sys_sendmsg+0x3a5/0x3c0 [352.817096] ? kernel_sendmsg+0x30/0x30 [352.817873]? __ia32_sys_recvmmsg+0x150/0x150 [ 352.818753] ___sys_sendmsg+0xd8/0x140 [ 352.819518] ? sendmsg_copy_msghdr+0x110/0x110 [352.820402]? ___sys_recvmsg+0xf4/0x1a0 [352.821110]? __copy_msghdr_from_user+0x260/0x260 [352.821934]? _raw_spin_lock+0x81/0xd0 [352.822680]? __handle_mm_fault+0xef3/0x1b20 [352.823549]? rb_insert_color+0x2a/0x270 [352.824373]? copy_page_range+0x16b0/0x16b0 [352.825209]? perf_event_update_userpage+0x2d0/0x2d0 [352.826190]? __fget_light+0xd9/0xf0 [ 352.826941] __sys_sendmsg+0xb3/0x130 [ 352.827613] ? __sys_sendmsg_sock+0x20/0x20 [352.828377]? do_user_addr_fault+0x2c5/0x8a0 [352.829184]? fpregs_assert_state_consistent+0x52/0x60 [352.830001]? exit_to_user_mode_prepare+0x32/0x160 [ 352.830845] do_syscall_64+0x35/0x80 [ 352.831445] Entry_SYSCALL_64_after_hwframe+0x44/0xae [ 352.832331] RIP: 0033:0x7f7bee973c1 7 [ ---truncado---"}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"CWE-416"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.3","versionEndExcluding":"5.4.151","matchCriteriaId":"C11443A3-881A-4C77-84D2-DEC0F4B10883"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.71","matchCriteriaId":"60C740E4-6C54-40CD-A914-2232D8FC781D"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.14.10","matchCriteriaId":"1A437B0D-8305-4C72-B691-D26986A126CF"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*","matchCriteriaId":"E46C74C6-B76B-4C94-A6A4-FD2FFF62D644"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*","matchCriteriaId":"60134C3A-06E4-48C1-B04F-2903732A4E56"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*","matchCriteriaId":"0460DA88-8FE1-46A2-9DDA-1F1ABA552E71"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/694b0cee7f8546b69a80996a29cb3cf4149c0453","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d0d520c19e7ea19ed38dc5797b12397b6ccf9f88","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d5ef190693a7d76c5c192d108e8dec48307b46ee","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/dab4677bdbffa5c8270e79e34e51c89efa0728a0","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/694b0cee7f8546b69a80996a29cb3cf4149c0453","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d0d520c19e7ea19ed38dc5797b12397b6ccf9f88","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d5ef190693a7d76c5c192d108e8dec48307b46ee","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/dab4677bdbffa5c8270e79e34e51c89efa0728a0","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]}]}}]}