CVE-2024-57996

{"id": "CVE-2024-57996", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"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"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-02-27T02:15:13.620", "references": [{"url": "https://git.kernel.org/stable/c/10685681bafce6febb39770f3387621bf5d67d0b", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/1b562b7f9231432da40d12e19786c1bd7df653a7", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/1e6d9d87626cf89eeffb4d943db12cb5b10bf961", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/35d0137305ae2f97260a9047f445bd4434bd6cc7", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/7d8947f2153ee9c5ab4cb17861a11cc45f30e8c4", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/7fefc294204f10a3405f175f4ac2be16d63f135e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/833e9a1c27b82024db7ff5038a51651f48f05e5e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-129"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet_sched: sch_sfq: don't allow 1 packet limit\n\nThe current implementation does not work correctly with a limit of\n1. iproute2 actually checks for this and this patch adds the check in\nkernel as well.\n\nThis fixes the following syzkaller reported crash:\n\nUBSAN: array-index-out-of-bounds in net/sched/sch_sfq.c:210:6\nindex 65535 is out of range for type 'struct sfq_head[128]'\nCPU: 0 PID: 2569 Comm: syz-executor101 Not tainted 5.10.0-smp-DEV #1\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\nCall Trace:\n __dump_stack lib/dump_stack.c:79 [inline]\n dump_stack+0x125/0x19f lib/dump_stack.c:120\n ubsan_epilogue lib/ubsan.c:148 [inline]\n __ubsan_handle_out_of_bounds+0xed/0x120 lib/ubsan.c:347\n sfq_link net/sched/sch_sfq.c:210 [inline]\n sfq_dec+0x528/0x600 net/sched/sch_sfq.c:238\n sfq_dequeue+0x39b/0x9d0 net/sched/sch_sfq.c:500\n sfq_reset+0x13/0x50 net/sched/sch_sfq.c:525\n qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026\n tbf_reset+0x3d/0x100 net/sched/sch_tbf.c:319\n qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026\n dev_reset_queue+0x8c/0x140 net/sched/sch_generic.c:1296\n netdev_for_each_tx_queue include/linux/netdevice.h:2350 [inline]\n dev_deactivate_many+0x6dc/0xc20 net/sched/sch_generic.c:1362\n __dev_close_many+0x214/0x350 net/core/dev.c:1468\n dev_close_many+0x207/0x510 net/core/dev.c:1506\n unregister_netdevice_many+0x40f/0x16b0 net/core/dev.c:10738\n unregister_netdevice_queue+0x2be/0x310 net/core/dev.c:10695\n unregister_netdevice include/linux/netdevice.h:2893 [inline]\n __tun_detach+0x6b6/0x1600 drivers/net/tun.c:689\n tun_detach drivers/net/tun.c:705 [inline]\n tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3640\n __fput+0x203/0x840 fs/file_table.c:280\n task_work_run+0x129/0x1b0 kernel/task_work.c:185\n exit_task_work include/linux/task_work.h:33 [inline]\n do_exit+0x5ce/0x2200 kernel/exit.c:931\n do_group_exit+0x144/0x310 kernel/exit.c:1046\n __do_sys_exit_group kernel/exit.c:1057 [inline]\n __se_sys_exit_group kernel/exit.c:1055 [inline]\n __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1055\n do_syscall_64+0x6c/0xd0\n entry_SYSCALL_64_after_hwframe+0x61/0xcb\nRIP: 0033:0x7fe5e7b52479\nCode: Unable to access opcode bytes at RIP 0x7fe5e7b5244f.\nRSP: 002b:00007ffd3c800398 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7\nRAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe5e7b52479\nRDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000\nRBP: 00007fe5e7bcd2d0 R08: ffffffffffffffb8 R09: 0000000000000014\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5e7bcd2d0\nR13: 0000000000000000 R14: 00007fe5e7bcdd20 R15: 00007fe5e7b24270\n\nThe crash can be also be reproduced with the following (with a tc\nrecompiled to allow for sfq limits of 1):\n\ntc qdisc add dev dummy0 handle 1: root tbf rate 1Kbit burst 100b lat 1s\n../iproute2-6.9.0/tc/tc qdisc add dev dummy0 handle 2: parent 1:10 sfq limit 1\nifconfig dummy0 up\nping -I dummy0 -f -c2 -W0.1 8.8.8.8\nsleep 1\n\nScenario that triggers the crash:\n\n* the first packet is sent and queued in TBF and SFQ; qdisc qlen is 1\n\n* TBF dequeues: it peeks from SFQ which moves the packet to the\n gso_skb list and keeps qdisc qlen set to 1. TBF is out of tokens so\n it schedules itself for later.\n\n* the second packet is sent and TBF tries to queues it to SFQ. qdisc\n qlen is now 2 and because the SFQ limit is 1 the packet is dropped\n by SFQ. At this point qlen is 1, and all of the SFQ slots are empty,\n however q->tail is not NULL.\n\nAt this point, assuming no more packets are queued, when sch_dequeue\nruns again it will decrement the qlen for the current empty slot\ncausing an underflow and the subsequent out of bounds access."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net_sched: sch_sfq: no permitir l\u00edmite de 1 paquete La implementaci\u00f3n actual no funciona correctamente con un l\u00edmite de 1. iproute2 en realidad verifica esto y este parche tambi\u00e9n agrega la verificaci\u00f3n en el kernel. Esto corrige el siguiente fallo informado por syzkaller reported crash: UBSAN: array-index-out-of-bounds in net/sched/sch_sfq.c:210:6 index 65535 is out of range for type 'struct sfq_head[128]' CPU: 0 PID: 2569 Comm: syz-executor101 Not tainted 5.10.0-smp-DEV #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x125/0x19f lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:148 [inline] __ubsan_handle_out_of_bounds+0xed/0x120 lib/ubsan.c:347 sfq_link net/sched/sch_sfq.c:210 [inline] sfq_dec+0x528/0x600 net/sched/sch_sfq.c:238 sfq_dequeue+0x39b/0x9d0 net/sched/sch_sfq.c:500 sfq_reset+0x13/0x50 net/sched/sch_sfq.c:525 qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026 tbf_reset+0x3d/0x100 net/sched/sch_tbf.c:319 qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026 dev_reset_queue+0x8c/0x140 net/sched/sch_generic.c:1296 netdev_for_each_tx_queue include/linux/netdevice.h:2350 [inline] dev_deactivate_many+0x6dc/0xc20 net/sched/sch_generic.c:1362 __dev_close_many+0x214/0x350 net/core/dev.c:1468 dev_close_many+0x207/0x510 net/core/dev.c:1506 unregister_netdevice_many+0x40f/0x16b0 net/core/dev.c:10738 unregister_netdevice_queue+0x2be/0x310 net/core/dev.c:10695 unregister_netdevice include/linux/netdevice.h:2893 [inline] __tun_detach+0x6b6/0x1600 drivers/net/tun.c:689 tun_detach drivers/net/tun.c:705 [inline] tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3640 __fput+0x203/0x840 fs/file_table.c:280 task_work_run+0x129/0x1b0 kernel/task_work.c:185 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x5ce/0x2200 kernel/exit.c:931 do_group_exit+0x144/0x310 kernel/exit.c:1046 __do_sys_exit_group kernel/exit.c:1057 [inline] __se_sys_exit_group kernel/exit.c:1055 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1055 do_syscall_64+0x6c/0xd0 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fe5e7b52479 Code: Unable to access opcode bytes at RIP 0x7fe5e7b5244f. RSP: 002b:00007ffd3c800398 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe5e7b52479 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007fe5e7bcd2d0 R08: ffffffffffffffb8 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5e7bcd2d0 R13: 0000000000000000 R14: 00007fe5e7bcdd20 R15: 00007fe5e7b24270 The crash can be also be reproduced with the following (with a tc recompiled to allow for sfq limits of 1): tc qdisc add dev dummy0 handle 1: root tbf rate 1Kbit burst 100b lat 1s ../iproute2-6.9.0/tc/tc qdisc add dev dummy0 handle 2: parent 1:10 sfq limit 1 ifconfig dummy0 up ping -I dummy0 -f -c2 -W0.1 8.8.8.8 sleep 1 Scenario that triggers the crash: * the first packet is sent and queued in TBF and SFQ; qdisc qlen is 1 * TBF dequeues: it peeks from SFQ which moves the packet to the gso_skb list and keeps qdisc qlen set to 1. TBF is out of tokens so it schedules itself for later. * the second packet is sent and TBF tries to queues it to SFQ. qdisc qlen is now 2 and because the SFQ limit is 1 the packet is dropped by SFQ. At this point qlen is 1, and all of the SFQ slots are empty, however q->tail is not NULL. En este punto, asumiendo que no hay m\u00e1s paquetes en cola, cuando sch_dequeue se ejecute nuevamente, disminuir\u00e1 el qlen para la ranura vac\u00eda actual, lo que provocar\u00e1 un desbordamiento y el posterior acceso fuera de l\u00edmites."}], "lastModified": "2025-06-27T11:15:24.037", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7CFA9ED9-656E-463E-A661-B2C4369D63EB", "versionEndExcluding": "6.1.129", "versionStartIncluding": "2.6.12"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A6D70701-9CB6-4222-A957-00A419878993", "versionEndExcluding": "6.6.76", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2897389C-A8C3-4D69-90F2-E701B3D66373", "versionEndExcluding": "6.12.13", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6D4116B1-1BFD-4F23-BA84-169CC05FC5A3", "versionEndExcluding": "6.13.2", "versionStartIncluding": "6.13"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}