GHSA-MC9G-H8JV-5CP3
Vulnerability from github – Published: 2026-05-27 15:33 – Updated: 2026-05-27 15:33In the Linux kernel, the following vulnerability has been resolved:
bonding: alb: fix UAF in rlb_arp_recv during bond up/down
The ALB RX path may access rx_hashtbl concurrently with bond teardown. During rapid bond up/down cycles, rlb_deinitialize() frees rx_hashtbl while RX handlers are still running, leading to a null pointer dereference detected by KASAN.
However, the root cause is that rlb_arp_recv() can still be accessed after setting recv_probe to NULL, which is actually a use-after-free (UAF) issue. That is the reason for using the referenced commit in the Fixes tag.
[ 214.174138] Oops: general protection fault, probably for non-canonical address 0xdffffc000000001d: 0000 [#1] SMP KASAN PTI [ 214.186478] KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef] [ 214.194933] CPU: 30 UID: 0 PID: 2375 Comm: ping Kdump: loaded Not tainted 6.19.0-rc8+ #2 PREEMPT(voluntary) [ 214.205907] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.14.0 01/14/2022 [ 214.214357] RIP: 0010:rlb_arp_recv+0x505/0xab0 [bonding] [ 214.220320] Code: 0f 85 2b 05 00 00 48 b8 00 00 00 00 00 fc ff df 40 0f b6 ed 48 c1 e5 06 49 03 ad 78 01 00 00 48 8d 7d 28 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 12 05 00 00 80 7d 28 00 0f 84 8c 00 [ 214.241280] RSP: 0018:ffffc900073d8870 EFLAGS: 00010206 [ 214.247116] RAX: dffffc0000000000 RBX: ffff888168556822 RCX: ffff88816855681e [ 214.255082] RDX: 000000000000001d RSI: dffffc0000000000 RDI: 00000000000000e8 [ 214.263048] RBP: 00000000000000c0 R08: 0000000000000002 R09: ffffed11192021c8 [ 214.271013] R10: ffff8888c9010e43 R11: 0000000000000001 R12: 1ffff92000e7b119 [ 214.278978] R13: ffff8888c9010e00 R14: ffff888168556822 R15: ffff888168556810 [ 214.286943] FS: 00007f85d2d9cb80(0000) GS:ffff88886ccb3000(0000) knlGS:0000000000000000 [ 214.295966] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 214.302380] CR2: 00007f0d047b5e34 CR3: 00000008a1c2e002 CR4: 00000000001726f0 [ 214.310347] Call Trace: [ 214.313070] [ 214.315318] ? __pfx_rlb_arp_recv+0x10/0x10 [bonding] [ 214.320975] bond_handle_frame+0x166/0xb60 [bonding] [ 214.326537] ? __pfx_bond_handle_frame+0x10/0x10 [bonding] [ 214.332680] __netif_receive_skb_core.constprop.0+0x576/0x2710 [ 214.339199] ? __pfx_arp_process+0x10/0x10 [ 214.343775] ? sched_balance_find_src_group+0x98/0x630 [ 214.349513] ? __pfxnetifreceive_skb_core.constprop.0+0x10/0x10 [ 214.356513] ? arp_rcv+0x307/0x690 [ 214.360311] ? pfx_arp_rcv+0x10/0x10 [ 214.364499] ? __lock_acquire+0x58c/0xbd0 [ 214.368975] __netif_receive_skb_one_core+0xae/0x1b0 [ 214.374518] ? __pfxnetifreceive_skb_one_core+0x10/0x10 [ 214.380743] ? lock_acquire+0x10b/0x140 [ 214.385026] process_backlog+0x3f1/0x13a0 [ 214.389502] ? process_backlog+0x3aa/0x13a0 [ 214.394174] napi_poll.constprop.0+0x9f/0x370 [ 214.399233] net_rx_action+0x8c1/0xe60 [ 214.403423] ? __pfx_net_rx_action+0x10/0x10 [ 214.408193] ? lock_acquire.part.0+0xbd/0x260 [ 214.413058] ? sched_clock_cpu+0x6c/0x540 [ 214.417540] ? mark_held_locks+0x40/0x70 [ 214.421920] handle_softirqs+0x1fd/0x860 [ 214.426302] ? __pfx_handle_softirqs+0x10/0x10 [ 214.431264] ? __neigh_event_send+0x2d6/0xf50 [ 214.436131] do_softirq+0xb1/0xf0 [ 214.439830]
The issue is reproducible by repeatedly running ip link set bond0 up/down while receiving ARP messages, where rlb_arp_recv() can race with rlb_deinitialize() and dereference a freed rx_hashtbl entry.
Fix this by setting recv_probe to NULL and then calling synchronize_net() to wait for any concurrent RX processing to finish. This ensures that no RX handler can access rx_hashtbl after it is freed in bond_alb_deinitialize().
{
"affected": [],
"aliases": [
"CVE-2026-45970"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-05-27T14:17:13Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbonding: alb: fix UAF in rlb_arp_recv during bond up/down\n\nThe ALB RX path may access rx_hashtbl concurrently with bond\nteardown. During rapid bond up/down cycles, rlb_deinitialize()\nfrees rx_hashtbl while RX handlers are still running, leading\nto a null pointer dereference detected by KASAN.\n\nHowever, the root cause is that rlb_arp_recv() can still be accessed\nafter setting recv_probe to NULL, which is actually a use-after-free\n(UAF) issue. That is the reason for using the referenced commit in the\nFixes tag.\n\n[ 214.174138] Oops: general protection fault, probably for non-canonical address 0xdffffc000000001d: 0000 [#1] SMP KASAN PTI\n[ 214.186478] KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef]\n[ 214.194933] CPU: 30 UID: 0 PID: 2375 Comm: ping Kdump: loaded Not tainted 6.19.0-rc8+ #2 PREEMPT(voluntary)\n[ 214.205907] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.14.0 01/14/2022\n[ 214.214357] RIP: 0010:rlb_arp_recv+0x505/0xab0 [bonding]\n[ 214.220320] Code: 0f 85 2b 05 00 00 48 b8 00 00 00 00 00 fc ff df 40 0f b6 ed 48 c1 e5 06 49 03 ad 78 01 00 00 48 8d 7d 28 48 89 fa 48 c1 ea 03 \u003c0f\u003e b6\n 04 02 84 c0 74 06 0f 8e 12 05 00 00 80 7d 28 00 0f 84 8c 00\n[ 214.241280] RSP: 0018:ffffc900073d8870 EFLAGS: 00010206\n[ 214.247116] RAX: dffffc0000000000 RBX: ffff888168556822 RCX: ffff88816855681e\n[ 214.255082] RDX: 000000000000001d RSI: dffffc0000000000 RDI: 00000000000000e8\n[ 214.263048] RBP: 00000000000000c0 R08: 0000000000000002 R09: ffffed11192021c8\n[ 214.271013] R10: ffff8888c9010e43 R11: 0000000000000001 R12: 1ffff92000e7b119\n[ 214.278978] R13: ffff8888c9010e00 R14: ffff888168556822 R15: ffff888168556810\n[ 214.286943] FS: 00007f85d2d9cb80(0000) GS:ffff88886ccb3000(0000) knlGS:0000000000000000\n[ 214.295966] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 214.302380] CR2: 00007f0d047b5e34 CR3: 00000008a1c2e002 CR4: 00000000001726f0\n[ 214.310347] Call Trace:\n[ 214.313070] \u003cIRQ\u003e\n[ 214.315318] ? __pfx_rlb_arp_recv+0x10/0x10 [bonding]\n[ 214.320975] bond_handle_frame+0x166/0xb60 [bonding]\n[ 214.326537] ? __pfx_bond_handle_frame+0x10/0x10 [bonding]\n[ 214.332680] __netif_receive_skb_core.constprop.0+0x576/0x2710\n[ 214.339199] ? __pfx_arp_process+0x10/0x10\n[ 214.343775] ? sched_balance_find_src_group+0x98/0x630\n[ 214.349513] ? __pfx___netif_receive_skb_core.constprop.0+0x10/0x10\n[ 214.356513] ? arp_rcv+0x307/0x690\n[ 214.360311] ? __pfx_arp_rcv+0x10/0x10\n[ 214.364499] ? __lock_acquire+0x58c/0xbd0\n[ 214.368975] __netif_receive_skb_one_core+0xae/0x1b0\n[ 214.374518] ? __pfx___netif_receive_skb_one_core+0x10/0x10\n[ 214.380743] ? lock_acquire+0x10b/0x140\n[ 214.385026] process_backlog+0x3f1/0x13a0\n[ 214.389502] ? process_backlog+0x3aa/0x13a0\n[ 214.394174] __napi_poll.constprop.0+0x9f/0x370\n[ 214.399233] net_rx_action+0x8c1/0xe60\n[ 214.403423] ? __pfx_net_rx_action+0x10/0x10\n[ 214.408193] ? lock_acquire.part.0+0xbd/0x260\n[ 214.413058] ? sched_clock_cpu+0x6c/0x540\n[ 214.417540] ? mark_held_locks+0x40/0x70\n[ 214.421920] handle_softirqs+0x1fd/0x860\n[ 214.426302] ? __pfx_handle_softirqs+0x10/0x10\n[ 214.431264] ? __neigh_event_send+0x2d6/0xf50\n[ 214.436131] do_softirq+0xb1/0xf0\n[ 214.439830] \u003c/IRQ\u003e\n\nThe issue is reproducible by repeatedly running\nip link set bond0 up/down while receiving ARP messages, where\nrlb_arp_recv() can race with rlb_deinitialize() and dereference\na freed rx_hashtbl entry.\n\nFix this by setting recv_probe to NULL and then calling\nsynchronize_net() to wait for any concurrent RX processing to finish.\nThis ensures that no RX handler can access rx_hashtbl after it is freed\nin bond_alb_deinitialize().",
"id": "GHSA-mc9g-h8jv-5cp3",
"modified": "2026-05-27T15:33:18Z",
"published": "2026-05-27T15:33:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45970"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c65cdf46ce340c9c00fbbaf84599d2daff43626e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d31065526f160ee0244a719230aa069daca2bf4d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/db5435b5342e3aaa4521d0f3ccfe94316b253ca1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/de7c097800f07f3c108185c7a38b53a530ba30ff"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e6834a4c474697df23ab9948fd3577b26bf48656"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f94a0de7b9f32745a14a1621c63087a092823587"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fd54ddc929be1d6c3b3b7b35d6d4642a5d9e803c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fef13c403be3fb685cb06419e6b3623106aab5ba"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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