CVE-2023-54193
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_api: remove block_cb from driver_list before freeing Error handler of tcf_block_bind() frees the whole bo->cb_list on error. However, by that time the flow_block_cb instances are already in the driver list because driver ndo_setup_tc() callback is called before that up the call chain in tcf_block_offload_cmd(). This leaves dangling pointers to freed objects in the list and causes use-after-free[0]. Fix it by also removing flow_block_cb instances from driver_list before deallocating them. [0]: [ 279.868433] ================================================================== [ 279.869964] BUG: KASAN: slab-use-after-free in flow_block_cb_setup_simple+0x631/0x7c0 [ 279.871527] Read of size 8 at addr ffff888147e2bf20 by task tc/2963 [ 279.873151] CPU: 6 PID: 2963 Comm: tc Not tainted 6.3.0-rc6+ #4 [ 279.874273] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 279.876295] Call Trace: [ 279.876882] <TASK> [ 279.877413] dump_stack_lvl+0x33/0x50 [ 279.878198] print_report+0xc2/0x610 [ 279.878987] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.879994] kasan_report+0xae/0xe0 [ 279.880750] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.881744] ? mlx5e_tc_reoffload_flows_work+0x240/0x240 [mlx5_core] [ 279.883047] flow_block_cb_setup_simple+0x631/0x7c0 [ 279.884027] tcf_block_offload_cmd.isra.0+0x189/0x2d0 [ 279.885037] ? tcf_block_setup+0x6b0/0x6b0 [ 279.885901] ? mutex_lock+0x7d/0xd0 [ 279.886669] ? __mutex_unlock_slowpath.constprop.0+0x2d0/0x2d0 [ 279.887844] ? ingress_init+0x1c0/0x1c0 [sch_ingress] [ 279.888846] tcf_block_get_ext+0x61c/0x1200 [ 279.889711] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.890682] ? clsact_init+0x2b0/0x2b0 [sch_ingress] [ 279.891701] qdisc_create+0x401/0xea0 [ 279.892485] ? qdisc_tree_reduce_backlog+0x470/0x470 [ 279.893473] tc_modify_qdisc+0x6f7/0x16d0 [ 279.894344] ? tc_get_qdisc+0xac0/0xac0 [ 279.895213] ? mutex_lock+0x7d/0xd0 [ 279.896005] ? __mutex_lock_slowpath+0x10/0x10 [ 279.896910] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.897770] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.898672] ? __sys_sendmsg+0xb5/0x140 [ 279.899494] ? do_syscall_64+0x3d/0x90 [ 279.900302] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.901337] ? kasan_save_stack+0x2e/0x40 [ 279.902177] ? kasan_save_stack+0x1e/0x40 [ 279.903058] ? kasan_set_track+0x21/0x30 [ 279.903913] ? kasan_save_free_info+0x2a/0x40 [ 279.904836] ? ____kasan_slab_free+0x11a/0x1b0 [ 279.905741] ? kmem_cache_free+0x179/0x400 [ 279.906599] netlink_rcv_skb+0x12c/0x360 [ 279.907450] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.908360] ? netlink_ack+0x1550/0x1550 [ 279.909192] ? rhashtable_walk_peek+0x170/0x170 [ 279.910135] ? kmem_cache_alloc_node+0x1af/0x390 [ 279.911086] ? _copy_from_iter+0x3d6/0xc70 [ 279.912031] netlink_unicast+0x553/0x790 [ 279.912864] ? netlink_attachskb+0x6a0/0x6a0 [ 279.913763] ? netlink_recvmsg+0x416/0xb50 [ 279.914627] netlink_sendmsg+0x7a1/0xcb0 [ 279.915473] ? netlink_unicast+0x790/0x790 [ 279.916334] ? iovec_from_user.part.0+0x4d/0x220 [ 279.917293] ? netlink_unicast+0x790/0x790 [ 279.918159] sock_sendmsg+0xc5/0x190 [ 279.918938] ____sys_sendmsg+0x535/0x6b0 [ 279.919813] ? import_iovec+0x7/0x10 [ 279.920601] ? kernel_sendmsg+0x30/0x30 [ 279.921423] ? __copy_msghdr+0x3c0/0x3c0 [ 279.922254] ? import_iovec+0x7/0x10 [ 279.923041] ___sys_sendmsg+0xeb/0x170 [ 279.923854] ? copy_msghdr_from_user+0x110/0x110 [ 279.924797] ? ___sys_recvmsg+0xd9/0x130 [ 279.925630] ? __perf_event_task_sched_in+0x183/0x470 [ 279.926656] ? ___sys_sendmsg+0x170/0x170 [ 279.927529] ? ctx_sched_in+0x530/0x530 [ 279.928369] ? update_curr+0x283/0x4f0 [ 279.929185] ? perf_event_update_userpage+0x570/0x570 [ 279.930201] ? __fget_light+0x57/0x520 [ 279.931023] ? __switch_to+0x53d/0xe70 [ 27 ---truncated---
View original CVE JSON
{
"id": "CVE-2023-54193",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-12-30T13:16:07.320",
"lastModified": "2026-10-28T19:10:00.193",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_api: remove block_cb from driver_list before freeing\n\nError handler of tcf_block_bind() frees the whole bo->cb_list on error.\nHowever, by that time the flow_block_cb instances are already in the driver\nlist because driver ndo_setup_tc() callback is called before that up the\ncall chain in tcf_block_offload_cmd(). This leaves dangling pointers to\nfreed objects in the list and causes use-after-free[0]. Fix it by also\nremoving flow_block_cb instances from driver_list before deallocating them.\n\n[0]:\n[ 279.868433] ==================================================================\n[ 279.869964] BUG: KASAN: slab-use-after-free in flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.871527] Read of size 8 at addr ffff888147e2bf20 by task tc/2963\n\n[ 279.873151] CPU: 6 PID: 2963 Comm: tc Not tainted 6.3.0-rc6+ #4\n[ 279.874273] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 279.876295] Call Trace:\n[ 279.876882] <TASK>\n[ 279.877413] dump_stack_lvl+0x33/0x50\n[ 279.878198] print_report+0xc2/0x610\n[ 279.878987] ? flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.879994] kasan_report+0xae/0xe0\n[ 279.880750] ? flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.881744] ? mlx5e_tc_reoffload_flows_work+0x240/0x240 [mlx5_core]\n[ 279.883047] flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.884027] tcf_block_offload_cmd.isra.0+0x189/0x2d0\n[ 279.885037] ? tcf_block_setup+0x6b0/0x6b0\n[ 279.885901] ? mutex_lock+0x7d/0xd0\n[ 279.886669] ? __mutex_unlock_slowpath.constprop.0+0x2d0/0x2d0\n[ 279.887844] ? ingress_init+0x1c0/0x1c0 [sch_ingress]\n[ 279.888846] tcf_block_get_ext+0x61c/0x1200\n[ 279.889711] ingress_init+0x112/0x1c0 [sch_ingress]\n[ 279.890682] ? clsact_init+0x2b0/0x2b0 [sch_ingress]\n[ 279.891701] qdisc_create+0x401/0xea0\n[ 279.892485] ? qdisc_tree_reduce_backlog+0x470/0x470\n[ 279.893473] tc_modify_qdisc+0x6f7/0x16d0\n[ 279.894344] ? tc_get_qdisc+0xac0/0xac0\n[ 279.895213] ? mutex_lock+0x7d/0xd0\n[ 279.896005] ? __mutex_lock_slowpath+0x10/0x10\n[ 279.896910] rtnetlink_rcv_msg+0x5fe/0x9d0\n[ 279.897770] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 279.898672] ? __sys_sendmsg+0xb5/0x140\n[ 279.899494] ? do_syscall_64+0x3d/0x90\n[ 279.900302] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 279.901337] ? kasan_save_stack+0x2e/0x40\n[ 279.902177] ? kasan_save_stack+0x1e/0x40\n[ 279.903058] ? kasan_set_track+0x21/0x30\n[ 279.903913] ? kasan_save_free_info+0x2a/0x40\n[ 279.904836] ? ____kasan_slab_free+0x11a/0x1b0\n[ 279.905741] ? kmem_cache_free+0x179/0x400\n[ 279.906599] netlink_rcv_skb+0x12c/0x360\n[ 279.907450] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 279.908360] ? netlink_ack+0x1550/0x1550\n[ 279.909192] ? rhashtable_walk_peek+0x170/0x170\n[ 279.910135] ? kmem_cache_alloc_node+0x1af/0x390\n[ 279.911086] ? _copy_from_iter+0x3d6/0xc70\n[ 279.912031] netlink_unicast+0x553/0x790\n[ 279.912864] ? netlink_attachskb+0x6a0/0x6a0\n[ 279.913763] ? netlink_recvmsg+0x416/0xb50\n[ 279.914627] netlink_sendmsg+0x7a1/0xcb0\n[ 279.915473] ? netlink_unicast+0x790/0x790\n[ 279.916334] ? iovec_from_user.part.0+0x4d/0x220\n[ 279.917293] ? netlink_unicast+0x790/0x790\n[ 279.918159] sock_sendmsg+0xc5/0x190\n[ 279.918938] ____sys_sendmsg+0x535/0x6b0\n[ 279.919813] ? import_iovec+0x7/0x10\n[ 279.920601] ? kernel_sendmsg+0x30/0x30\n[ 279.921423] ? __copy_msghdr+0x3c0/0x3c0\n[ 279.922254] ? import_iovec+0x7/0x10\n[ 279.923041] ___sys_sendmsg+0xeb/0x170\n[ 279.923854] ? copy_msghdr_from_user+0x110/0x110\n[ 279.924797] ? ___sys_recvmsg+0xd9/0x130\n[ 279.925630] ? __perf_event_task_sched_in+0x183/0x470\n[ 279.926656] ? ___sys_sendmsg+0x170/0x170\n[ 279.927529] ? ctx_sched_in+0x530/0x530\n[ 279.928369] ? update_curr+0x283/0x4f0\n[ 279.929185] ? perf_event_update_userpage+0x570/0x570\n[ 279.930201] ? __fget_light+0x57/0x520\n[ 279.931023] ? __switch_to+0x53d/0xe70\n[ 27\n---truncated---"
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/sched: cls_api: eliminar block_cb de driver_list antes de liberar\n\nEl manejador de errores de tcf_block_bind() libera toda la bo -> cb_list en caso de error. Sin embargo, para ese momento las instancias de flow_block_cb ya están en la lista del controlador porque la llamada de retorno ndo_setup_tc() del controlador se invoca antes de eso en la cadena de llamadas en tcf_block_offload_cmd(). Esto deja punteros colgantes a objetos liberados en la lista y causa uso después de liberación[0]. Corríjalo también eliminando las instancias de flow_block_cb de driver_list antes de desasignarlas.\n\n[0]:\n[ 279.868433] ==================================================================\n[ 279.869964] BUG: KASAN: slab-uso después de liberación en flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.871527] Lectura de tamaño 8 en la dirección ffff888147e2bf20 por la tarea tc/2963\n\n[ 279.873151] CPU: 6 PID: 2963 Comm: tc No contaminado 6.3.0-rc6+ #4\n[ 279.874273] Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 279.876295] Traza de Llamada:\n[ 279.876882] [TAREA]\n[ 279.877413] dump_stack_lvl+0x33/0x50\n[ 279.878198] print_report+0xc2/0x610\n[ 279.878987] ? flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.879994] kasan_report+0xae/0xe0\n[ 279.880750] ? flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.881744] ? mlx5e_tc_reoffload_flows_work+0x240/0x240 [mlx5_core]\n[ 279.883047] flow_block_cb_setup_simple+0x631/0x7c0\n[ 279.884027] tcf_block_offload_cmd.isra.0+0x189/0x2d0\n[ 279.885037] ? tcf_block_setup+0x6b0/0x6b0\n[ 279.885901] ? mutex_lock+0x7d/0xd0\n[ 279.886669] ? __mutex_unlock_slowpath.constprop.0+0x2d0/0x2d0\n[ 279.887844] ? ingress_init+0x1c0/0x1c0 [sch_ingress]\n[ 279.888846] tcf_block_get_ext+0x61c/0x1200\n[ 279.889711] ingress_init+0x112/0x1c0 [sch_ingress]\n[ 279.890682] ? clsact_init+0x2b0/0x2b0 [sch_ingress]\n[ 279.891701] qdisc_create+0x401/0xea0\n[ 279.892485] ? qdisc_tree_reduce_backlog+0x470/0x470\n[ 279.893473] tc_modify_qdisc+0x6f7/0x16d0\n[ 279.894344] ? tc_get_qdisc+0xac0/0xac0\n[ 279.895213] ? mutex_lock+0x7d/0xd0\n[ 279.896005] ? __mutex_lock_slowpath+0x10/0x10\n[ 279.896910] rtnetlink_rcv_msg+0x5fe/0x9d0\n[ 279.897770] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 279.898672] ? __sys_sendmsg+0xb5/0x140\n[ 279.899494] ? do_syscall_64+0x3d/0x90\n[ 279.900302] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 279.901337] ? kasan_save_stack+0x2e/0x40\n[ 279.902177] ? kasan_save_stack+0x1e/0x40\n[ 279.903058] ? kasan_set_track+0x21/0x30\n[ 279.903913] ? kasan_save_free_info+0x2a/0x40\n[ 279.904836] ? ____kasan_slab_free+0x11a/0x1b0\n[ 279.905741] ? kmem_cache_free+0x179/0x400\n[ 279.906599] netlink_rcv_skb+0x12c/0x360\n[ 279.907450] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 279.908360] ? netlink_ack+0x1550/0x1550\n[ 279.909192] ? rhashtable_walk_peek+0x170/0x170\n[ 279.910135] ? kmem_cache_alloc_node+0x1af/0x390\n[ 279.911086] ? _copy_from_iter+0x3d6/0xc70\n[ 279.912031] netlink_unicast+0x553/0x790\n[ 279.912864] ? netlink_attachskb+0x6a0/0x6a0\n[ 279.913763] ? netlink_recvmsg+0x416/0xb50\n[ 279.914627] netlink_sendmsg+0x7a1/0xcb0\n[ 279.915473] ? netlink_unicast+0x790/0x790\n[ 279.916334] ? iovec_from_user.part.0+0x4d/0x220\n[ 279.917293] ? netlink_unicast+0x790/0x790\n[ 279.918159] sock_sendmsg+0xc5/0x190\n[ 279.918938] ____sys_sendmsg+0x535/0x6b0\n[ 279.919813] ? import_iovec+0x7/0x10\n[ 279.920601] ? kernel_sendmsg+0x30/0x30\n[ 279.921423] ? __copy_msghdr+0x3c0/0x3c0\n[ 279.922254] ? import_iovec+0x7/0x10\n[ 279.923041] ___sys_sendmsg+0xeb/0x170\n[ 279.923854] ? copy_msghdr_from_user+0x110/0x110\n[ 279.924797] ? ___sys_recvmsg+0xd9/0x130\n[ 279.925630] ? __perf_event_task_sched_in+0x183/0x470\n[ 279.926656] ? ___sys_sendmsg+0x170/0x170\n[ 279."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/sched/cls_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "cc5fe387c6294d0471cb7ed064efac97fac65ccc",
"versionType": "git",
"status": "affected"
},
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "7311c8be3755611bf6edea4dfbeb190b4bdd489f",
"versionType": "git",
"status": "affected"
},
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "cb145932fcf6814e7e95e467eb70e7849a845ae9",
"versionType": "git",
"status": "affected"
},
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "55866fe3fded3ce94ac3fc1bb3dfce654282f483",
"versionType": "git",
"status": "affected"
},
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "26aec72429a05e917d574eca0efc5306c63a8862",
"versionType": "git",
"status": "affected"
},
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "7b7a74ed303d532fb73ae4b1697f16a0fea89cd0",
"versionType": "git",
"status": "affected"
},
{
"version": "59094b1e5094c7e50a3d2912202fd30b6a1dadf8",
"lessThan": "da94a7781fc3c92e7df7832bc2746f4d39bc624e",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"net/sched/cls_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.3",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.3",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.4.243",
"lessThanOrEqual": "5.4.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.180",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.112",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.29",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.2.16",
"lessThanOrEqual": "6.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.3.3",
"lessThanOrEqual": "6.3.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.4",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"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
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-15T21:38:55.488795Z",
"id": "CVE-2023-54193",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/26aec72429a05e917d574eca0efc5306c63a8862",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/55866fe3fded3ce94ac3fc1bb3dfce654282f483",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7311c8be3755611bf6edea4dfbeb190b4bdd489f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7b7a74ed303d532fb73ae4b1697f16a0fea89cd0",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/cb145932fcf6814e7e95e467eb70e7849a845ae9",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/cc5fe387c6294d0471cb7ed064efac97fac65ccc",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/da94a7781fc3c92e7df7832bc2746f4d39bc624e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}