CVE-2021-47103 (GCVE-0-2021-47103)

Vulnerability from cvelistv5 – Published: 2024-03-04 18:10 – Updated: 2026-05-11 13:48
VLAI
Title
inet: fully convert sk->sk_rx_dst to RCU rules
Summary
In the Linux kernel, the following vulnerability has been resolved: inet: fully convert sk->sk_rx_dst to RCU rules syzbot reported various issues around early demux, one being included in this changelog [1] sk->sk_rx_dst is using RCU protection without clearly documenting it. And following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv() are not following standard RCU rules. [a] dst_release(dst); [b] sk->sk_rx_dst = NULL; They look wrong because a delete operation of RCU protected pointer is supposed to clear the pointer before the call_rcu()/synchronize_rcu() guarding actual memory freeing. In some cases indeed, dst could be freed before [b] is done. We could cheat by clearing sk_rx_dst before calling dst_release(), but this seems the right time to stick to standard RCU annotations and debugging facilities. [1] BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline] BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792 Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204 CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 dst_check include/net/dst.h:470 [inline] tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792 ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline] ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline] __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556 __netif_receive_skb_list net/core/dev.c:5608 [inline] netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699 gro_normal_list net/core/dev.c:5853 [inline] gro_normal_list net/core/dev.c:5849 [inline] napi_complete_done+0x1f1/0x880 net/core/dev.c:6590 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557 __napi_poll+0xaf/0x440 net/core/dev.c:7023 napi_poll net/core/dev.c:7090 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7177 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629 RIP: 0033:0x7f5e972bfd57 Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e <48> 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73 RSP: 002b:00007fff8a413210 EFLAGS: 00000283 RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45 RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45 RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9 R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0 R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019 </TASK> Allocated by task 13: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247 dst_alloc+0x146/0x1f0 net/core/dst.c:92 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613 ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:234 ---truncated---
Severity
No CVSS data available.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < 68c34ce11ef23328692aa35fa6aaafdd75913100 (git)
Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < 92e6e36ecd16808866ac6172b9491b5097cde449 (git)
Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < 75a578000ae5e511e5d0e8433c94a14d9c99c412 (git)
Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < c3bb4a7e8cbc984e1cdac0fe6af60e880214ed6e (git)
Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < f039b43cbaea5e0700980c2f0052da05a70782e0 (git)
Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < 0249a4b8a554f2eb6a27b62516fa50168584faa4 (git)
Affected: 41063e9dd11956f2d285e12e4342e1d232ba0ea2 , < 8f905c0e7354ef261360fb7535ea079b1082c105 (git)
Create a notification for this product.
Linux Linux Affected: 3.6
Unaffected: 0 , < 3.6 (semver)
Unaffected: 4.9.331 , ≤ 4.9.* (semver)
Unaffected: 4.14.296 , ≤ 4.14.* (semver)
Unaffected: 4.19.262 , ≤ 4.19.* (semver)
Unaffected: 5.4.220 , ≤ 5.4.* (semver)
Unaffected: 5.10.150 , ≤ 5.10.* (semver)
Unaffected: 5.15.12 , ≤ 5.15.* (semver)
Unaffected: 5.16 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ninet: fully convert sk-\u003esk_rx_dst to RCU rules\n\nsyzbot reported various issues around early demux,\none being included in this changelog [1]\n\nsk-\u003esk_rx_dst is using RCU protection without clearly\ndocumenting it.\n\nAnd following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()\nare not following standard RCU rules.\n\n[a]    dst_release(dst);\n[b]    sk-\u003esk_rx_dst = NULL;\n\nThey look wrong because a delete operation of RCU protected\npointer is supposed to clear the pointer before\nthe call_rcu()/synchronize_rcu() guarding actual memory freeing.\n\nIn some cases indeed, dst could be freed before [b] is done.\n\nWe could cheat by clearing sk_rx_dst before calling\ndst_release(), but this seems the right time to stick\nto standard RCU annotations and debugging facilities.\n\n[1]\nBUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]\nBUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792\nRead of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204\n\nCPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\n print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247\n __kasan_report mm/kasan/report.c:433 [inline]\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\n dst_check include/net/dst.h:470 [inline]\n tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792\n ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340\n ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583\n ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]\n ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644\n __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]\n __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556\n __netif_receive_skb_list net/core/dev.c:5608 [inline]\n netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699\n gro_normal_list net/core/dev.c:5853 [inline]\n gro_normal_list net/core/dev.c:5849 [inline]\n napi_complete_done+0x1f1/0x880 net/core/dev.c:6590\n virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]\n virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557\n __napi_poll+0xaf/0x440 net/core/dev.c:7023\n napi_poll net/core/dev.c:7090 [inline]\n net_rx_action+0x801/0xb40 net/core/dev.c:7177\n __do_softirq+0x29b/0x9c2 kernel/softirq.c:558\n invoke_softirq kernel/softirq.c:432 [inline]\n __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637\n irq_exit_rcu+0x5/0x20 kernel/softirq.c:649\n common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240\n asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629\nRIP: 0033:0x7f5e972bfd57\nCode: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e \u003c48\u003e 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73\nRSP: 002b:00007fff8a413210 EFLAGS: 00000283\nRAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45\nRDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45\nRBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9\nR10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0\nR13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019\n \u003c/TASK\u003e\n\nAllocated by task 13:\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\n kasan_set_track mm/kasan/common.c:46 [inline]\n set_alloc_info mm/kasan/common.c:434 [inline]\n __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467\n kasan_slab_alloc include/linux/kasan.h:259 [inline]\n slab_post_alloc_hook mm/slab.h:519 [inline]\n slab_alloc_node mm/slub.c:3234 [inline]\n slab_alloc mm/slub.c:3242 [inline]\n kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247\n dst_alloc+0x146/0x1f0 net/core/dst.c:92\n rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613\n ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:234\n---truncated---"
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    "nvd": "{\"cve\":{\"id\":\"CVE-2021-47103\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2024-03-04T18:15:08.667\",\"lastModified\":\"2025-02-14T15:03:01.997\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\ninet: fully convert sk-\u003esk_rx_dst to RCU rules\\n\\nsyzbot reported various issues around early demux,\\none being included in this changelog [1]\\n\\nsk-\u003esk_rx_dst is using RCU protection without clearly\\ndocumenting it.\\n\\nAnd following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()\\nare not following standard RCU rules.\\n\\n[a]    dst_release(dst);\\n[b]    sk-\u003esk_rx_dst = NULL;\\n\\nThey look wrong because a delete operation of RCU protected\\npointer is supposed to clear the pointer before\\nthe call_rcu()/synchronize_rcu() guarding actual memory freeing.\\n\\nIn some cases indeed, dst could be freed before [b] is done.\\n\\nWe could cheat by clearing sk_rx_dst before calling\\ndst_release(), but this seems the right time to stick\\nto standard RCU annotations and debugging facilities.\\n\\n[1]\\nBUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]\\nBUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792\\nRead of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204\\n\\nCPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0\\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\\nCall Trace:\\n \u003cTASK\u003e\\n __dump_stack lib/dump_stack.c:88 [inline]\\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\\n print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247\\n __kasan_report mm/kasan/report.c:433 [inline]\\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\\n dst_check include/net/dst.h:470 [inline]\\n tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792\\n ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340\\n ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583\\n ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]\\n ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644\\n __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]\\n __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556\\n __netif_receive_skb_list net/core/dev.c:5608 [inline]\\n netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699\\n gro_normal_list net/core/dev.c:5853 [inline]\\n gro_normal_list net/core/dev.c:5849 [inline]\\n napi_complete_done+0x1f1/0x880 net/core/dev.c:6590\\n virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]\\n virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557\\n __napi_poll+0xaf/0x440 net/core/dev.c:7023\\n napi_poll net/core/dev.c:7090 [inline]\\n net_rx_action+0x801/0xb40 net/core/dev.c:7177\\n __do_softirq+0x29b/0x9c2 kernel/softirq.c:558\\n invoke_softirq kernel/softirq.c:432 [inline]\\n __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637\\n irq_exit_rcu+0x5/0x20 kernel/softirq.c:649\\n common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240\\n asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629\\nRIP: 0033:0x7f5e972bfd57\\nCode: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e \u003c48\u003e 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73\\nRSP: 002b:00007fff8a413210 EFLAGS: 00000283\\nRAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45\\nRDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45\\nRBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9\\nR10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0\\nR13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019\\n \u003c/TASK\u003e\\n\\nAllocated by task 13:\\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\\n kasan_set_track mm/kasan/common.c:46 [inline]\\n set_alloc_info mm/kasan/common.c:434 [inline]\\n __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467\\n kasan_slab_alloc include/linux/kasan.h:259 [inline]\\n slab_post_alloc_hook mm/slab.h:519 [inline]\\n slab_alloc_node mm/slub.c:3234 [inline]\\n slab_alloc mm/slub.c:3242 [inline]\\n kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247\\n dst_alloc+0x146/0x1f0 net/core/dst.c:92\\n rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613\\n ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:234\\n---truncated---\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: inet: conversi\u00f3n completa de sk-\u0026gt;sk_rx_dst a reglas de RCU syzbot inform\u00f3 varios problemas relacionados con la demux inicial, uno de los cuales se incluye en este registro de cambios [1] sk-\u0026gt;sk_rx_dst est\u00e1 usando protecci\u00f3n de RCU sin claridad document\u00e1ndolo. Y las siguientes secuencias en tcp_v4_do_rcv()/tcp_v6_do_rcv() no siguen las reglas est\u00e1ndar de RCU. [a] dst_release(dst); [b] sk-\u0026gt;sk_rx_dst = NULL; Se ven incorrectos porque se supone que una operaci\u00f3n de eliminaci\u00f3n del puntero protegido de RCU borra el puntero antes de que call_rcu()/synchronize_rcu() proteja la liberaci\u00f3n de memoria real. De hecho, en algunos casos, dst podr\u00eda liberarse antes de que se realice [b]. Podr\u00edamos hacer trampa borrando sk_rx_dst antes de llamar a dst_release(), pero este parece el momento adecuado para ce\u00f1irnos a las anotaciones est\u00e1ndar de RCU y las funciones de depuraci\u00f3n.  [1] BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline] BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792 Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204 CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace:  __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 dst_check include/net/dst.h:470 [inline] tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792 ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline] ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline] __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556 __netif_receive_skb_list net/core/dev.c:5608 [inline] netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699 gro_normal_list net/core/dev.c:5853 [inline] gro_normal_list net/core/dev.c:5849 [inline] napi_complete_done+0x1f1/0x880 net/core/dev.c:6590 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557 __napi_poll+0xaf/0x440 net/core/dev.c:7023 napi_poll net/core/dev.c:7090 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7177 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629 RIP: 0033:0x7f5e972bfd57 Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e \u0026lt;48\u0026gt; 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73 RSP: 002b:00007fff8a413210 EFLAGS: 00000283 RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45 RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45 RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9 R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0 R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019  Allocated by task 13: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247 dst_alloc+0x146/0x1f0 net/core/dst.c:92 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613 ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:234\"}],\"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\":\"3.6\",\"versionEndExcluding\":\"4.9.331\",\"matchCriteriaId\":\"9ED924D8-78AE-4446-9153-4BB0847E96B7\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.10\",\"versionEndExcluding\":\"4.14.296\",\"matchCriteriaId\":\"1927ABC6-E0D2-478F-B103-B982A42D1158\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.15\",\"versionEndExcluding\":\"4.19.262\",\"matchCriteriaId\":\"D6B62970-1FAD-4ED6-930A-23E26A8D2E08\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.20\",\"versionEndExcluding\":\"5.4.220\",\"matchCriteriaId\":\"125F7133-B3B7-4175-8CF3-FF0845483254\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.5\",\"versionEndExcluding\":\"5.10.150\",\"matchCriteriaId\":\"C495821C-2A71-4F09-BED8-6A6EB4C9BA27\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.15.12\",\"matchCriteriaId\":\"732BA914-7B3B-43CD-857F-8119106F6F71\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"357AA433-37E8-4323-BFB2-3038D6E4B414\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"A73429BA-C2D9-4D0C-A75F-06A1CA8B3983\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.16:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"F621B5E3-E99D-49E7-90B9-EC3B77C95383\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.16:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"F7BFDCAA-1650-49AA-8462-407DD593F94F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.16:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"6EC9882F-866D-4ACB-8FBC-213D8D8436C8\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.16:rc6:*:*:*:*:*:*\",\"matchCriteriaId\":\"8A0915FE-A4AA-4C94-B783-CF29D81E7E54\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0249a4b8a554f2eb6a27b62516fa50168584faa4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Exploit\",\"Mailing 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\"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"41063e9dd11956f2d285e12e4342e1d232ba0ea2\", \"lessThan\": \"92e6e36ecd16808866ac6172b9491b5097cde449\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"41063e9dd11956f2d285e12e4342e1d232ba0ea2\", \"lessThan\": \"75a578000ae5e511e5d0e8433c94a14d9c99c412\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"41063e9dd11956f2d285e12e4342e1d232ba0ea2\", \"lessThan\": \"c3bb4a7e8cbc984e1cdac0fe6af60e880214ed6e\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"41063e9dd11956f2d285e12e4342e1d232ba0ea2\", \"lessThan\": \"f039b43cbaea5e0700980c2f0052da05a70782e0\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"41063e9dd11956f2d285e12e4342e1d232ba0ea2\", \"lessThan\": \"0249a4b8a554f2eb6a27b62516fa50168584faa4\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"41063e9dd11956f2d285e12e4342e1d232ba0ea2\", \"lessThan\": \"8f905c0e7354ef261360fb7535ea079b1082c105\", \"versionType\": \"git\"}], \"programFiles\": [\"include/net/sock.h\", \"net/ipv4/af_inet.c\", \"net/ipv4/tcp.c\", \"net/ipv4/tcp_input.c\", \"net/ipv4/tcp_ipv4.c\", \"net/ipv4/udp.c\", \"net/ipv6/tcp_ipv6.c\", \"net/ipv6/udp.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"3.6\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"3.6\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"4.9.331\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.9.*\"}, {\"status\": \"unaffected\", \"version\": \"4.14.296\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.14.*\"}, {\"status\": \"unaffected\", \"version\": \"4.19.262\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.19.*\"}, {\"status\": \"unaffected\", \"version\": \"5.4.220\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.4.*\"}, {\"status\": \"unaffected\", \"version\": \"5.10.150\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.15.12\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"5.16\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"include/net/sock.h\", \"net/ipv4/af_inet.c\", \"net/ipv4/tcp.c\", \"net/ipv4/tcp_input.c\", \"net/ipv4/tcp_ipv4.c\", \"net/ipv4/udp.c\", \"net/ipv6/tcp_ipv6.c\", \"net/ipv6/udp.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/68c34ce11ef23328692aa35fa6aaafdd75913100\"}, {\"url\": \"https://git.kernel.org/stable/c/92e6e36ecd16808866ac6172b9491b5097cde449\"}, {\"url\": \"https://git.kernel.org/stable/c/75a578000ae5e511e5d0e8433c94a14d9c99c412\"}, {\"url\": \"https://git.kernel.org/stable/c/c3bb4a7e8cbc984e1cdac0fe6af60e880214ed6e\"}, {\"url\": \"https://git.kernel.org/stable/c/f039b43cbaea5e0700980c2f0052da05a70782e0\"}, {\"url\": \"https://git.kernel.org/stable/c/0249a4b8a554f2eb6a27b62516fa50168584faa4\"}, {\"url\": \"https://git.kernel.org/stable/c/8f905c0e7354ef261360fb7535ea079b1082c105\"}], \"x_generator\": {\"engine\": \"bippy-5f407fcff5a0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\ninet: fully convert sk-\u003esk_rx_dst to RCU rules\\n\\nsyzbot reported various issues around early demux,\\none being included in this changelog [1]\\n\\nsk-\u003esk_rx_dst is using RCU protection without clearly\\ndocumenting it.\\n\\nAnd following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()\\nare not following standard RCU rules.\\n\\n[a]    dst_release(dst);\\n[b]    sk-\u003esk_rx_dst = NULL;\\n\\nThey look wrong because a delete operation of RCU protected\\npointer is supposed to clear the pointer before\\nthe call_rcu()/synchronize_rcu() guarding actual memory freeing.\\n\\nIn some cases indeed, dst could be freed before [b] is done.\\n\\nWe could cheat by clearing sk_rx_dst before calling\\ndst_release(), but this seems the right time to stick\\nto standard RCU annotations and debugging facilities.\\n\\n[1]\\nBUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]\\nBUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792\\nRead of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204\\n\\nCPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0\\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\\nCall Trace:\\n \u003cTASK\u003e\\n __dump_stack lib/dump_stack.c:88 [inline]\\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\\n print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247\\n __kasan_report mm/kasan/report.c:433 [inline]\\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\\n dst_check include/net/dst.h:470 [inline]\\n tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792\\n ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340\\n ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583\\n ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]\\n ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644\\n __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]\\n __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556\\n __netif_receive_skb_list net/core/dev.c:5608 [inline]\\n netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699\\n gro_normal_list net/core/dev.c:5853 [inline]\\n gro_normal_list net/core/dev.c:5849 [inline]\\n napi_complete_done+0x1f1/0x880 net/core/dev.c:6590\\n virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]\\n virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557\\n __napi_poll+0xaf/0x440 net/core/dev.c:7023\\n napi_poll net/core/dev.c:7090 [inline]\\n net_rx_action+0x801/0xb40 net/core/dev.c:7177\\n __do_softirq+0x29b/0x9c2 kernel/softirq.c:558\\n invoke_softirq kernel/softirq.c:432 [inline]\\n __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637\\n irq_exit_rcu+0x5/0x20 kernel/softirq.c:649\\n common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240\\n asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629\\nRIP: 0033:0x7f5e972bfd57\\nCode: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e \u003c48\u003e 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73\\nRSP: 002b:00007fff8a413210 EFLAGS: 00000283\\nRAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45\\nRDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45\\nRBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9\\nR10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0\\nR13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019\\n \u003c/TASK\u003e\\n\\nAllocated by task 13:\\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\\n kasan_set_track mm/kasan/common.c:46 [inline]\\n set_alloc_info mm/kasan/common.c:434 [inline]\\n __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467\\n kasan_slab_alloc include/linux/kasan.h:259 [inline]\\n slab_post_alloc_hook mm/slab.h:519 [inline]\\n slab_alloc_node mm/slub.c:3234 [inline]\\n slab_alloc mm/slub.c:3242 [inline]\\n kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247\\n dst_alloc+0x146/0x1f0 net/core/dst.c:92\\n rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613\\n ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:234\\n---truncated---\"}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2024-12-19T07:35:17.535Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2021-47103\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2024-12-19T07:35:17.535Z\", \"dateReserved\": \"2024-02-29T22:33:44.301Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2024-03-04T18:10:57.116Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.