CVE-2024-40923 in Linux
Summary
by MITRE • 07/12/2024
In the Linux kernel, the following vulnerability has been resolved:
vmxnet3: disable rx data ring on dma allocation failure
When vmxnet3_rq_create() fails to allocate memory for rq->data_ring.base, the subsequent call to vmxnet3_rq_destroy_all_rxdataring does not reset rq->data_ring.desc_size for the data ring that failed, which presumably causes the hypervisor to reference it on packet reception.
To fix this bug, rq->data_ring.desc_size needs to be set to 0 to tell the hypervisor to disable this feature.
[ 95.436876] kernel BUG at net/core/skbuff.c:207!
[ 95.439074] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 95.440411] CPU: 7 PID: 0 Comm: swapper/7 Not tainted 6.9.3-dirty #1
[ 95.441558] Hardware name: VMware, Inc. VMware Virtual
Platform/440BX Desktop Reference Platform, BIOS 6.00 12/12/2018 [ 95.443481] RIP: 0010:skb_panic+0x4d/0x4f
[ 95.444404] Code: 4f 70 50 8b 87 c0 00 00 00 50 8b 87 bc 00 00 00 50
ff b7 d0 00 00 00 4c 8b 8f c8 00 00 00 48 c7 c7 68 e8 be 9f e8 63 58 f9 ff 0b 48 8b 14 24 48 c7 c1 d0 73 65 9f e8 a1 ff ff ff 48 8b 14 24 [ 95.447684] RSP: 0018:ffffa13340274dd0 EFLAGS: 00010246
[ 95.448762] RAX: 0000000000000089 RBX: ffff8fbbc72b02d0 RCX: 000000000000083f
[ 95.450148] RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
[ 95.451520] RBP: 000000000000002d R08: 0000000000000000 R09: ffffa13340274c60
[ 95.452886] R10: ffffffffa04ed468 R11: 0000000000000002 R12: 0000000000000000
[ 95.454293] R13: ffff8fbbdab3c2d0 R14: ffff8fbbdbd829e0 R15: ffff8fbbdbd809e0
[ 95.455682] FS: 0000000000000000(0000) GS:ffff8fbeefd80000(0000) knlGS:0000000000000000
[ 95.457178] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 95.458340] CR2: 00007fd0d1f650c8 CR3: 0000000115f28000 CR4: 00000000000406f0
[ 95.459791] Call Trace:
[ 95.460515]
[ 95.461180] ? __die_body.cold+0x19/0x27
[ 95.462150] ? die+0x2e/0x50
[ 95.462976] ? do_trap+0xca/0x110
[ 95.463973] ? do_error_trap+0x6a/0x90
[ 95.464966] ? skb_panic+0x4d/0x4f
[ 95.465901] ? exc_invalid_op+0x50/0x70
[ 95.466849] ? skb_panic+0x4d/0x4f
[ 95.467718] ? asm_exc_invalid_op+0x1a/0x20
[ 95.468758] ? skb_panic+0x4d/0x4f
[ 95.469655] skb_put.cold+0x10/0x10
[ 95.470573] vmxnet3_rq_rx_complete+0x862/0x11e0 [vmxnet3]
[ 95.471853] vmxnet3_poll_rx_only+0x36/0xb0 [vmxnet3]
[ 95.473185] __napi_poll+0x2b/0x160
[ 95.474145] net_rx_action+0x2c6/0x3b0
[ 95.475115] handle_softirqs+0xe7/0x2a0
[ 95.476122] __irq_exit_rcu+0x97/0xb0
[ 95.477109] common_interrupt+0x85/0xa0
[ 95.478102]
[ 95.478846]
[ 95.479603] asm_common_interrupt+0x26/0x40
[ 95.480657] RIP: 0010:pv_native_safe_halt+0xf/0x20
[ 95.481801] Code: 22 d7 e9 54 87 01 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 93 ba 3b 00 fb f4 2c 87 01 00 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90
[ 95.485563] RSP: 0018:ffffa133400ffe58 EFLAGS: 00000246
[ 95.486882] RAX: 0000000000004000 RBX: ffff8fbbc1d14064 RCX: 0000000000000000
[ 95.488477] RDX: ffff8fbeefd80000 RSI: ffff8fbbc1d14000 RDI: 0000000000000001
[ 95.490067] RBP: ffff8fbbc1d14064 R08: ffffffffa0652260 R09: 00000000000010d3
[ 95.491683] R10: 0000000000000018 R11: ffff8fbeefdb4764 R12: ffffffffa0652260
[ 95.493389] R13: ffffffffa06522e0 R14: 0000000000000001 R15: 0000000000000000
[ 95.495035] acpi_safe_halt+0x14/0x20
[ 95.496127] acpi_idle_do_entry+0x2f/0x50
[ 95.497221] acpi_idle_enter+0x7f/0xd0
[ 95.498272] cpuidle_enter_state+0x81/0x420
[ 95.499375] cpuidle_enter+0x2d/0x40
[ 95.500400] do_idle+0x1e5/0x240
[ 95.501385] cpu_startup_entry+0x29/0x30
[ 95.502422] start_secondary+0x11c/0x140
[ 95.503454] common_startup_64+0x13e/0x141
[ 95.504466]
[ 95.505197] Modules linked in: nft_fib_inet nft_fib_ipv4
nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ip ---truncated---
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Analysis
by VulDB Data Team • 10/03/2025
The vulnerability CVE-2024-40923 affects the Linux kernel's vmxnet3 driver, which is used for virtual network interface cards in VMware environments. This issue stems from a failure in memory allocation handling within the receive queue data ring management, specifically in the vmxnet3_rq_create function. When memory allocation for the rq->data_ring.base fails, the subsequent cleanup process does not properly reset the rq->data_ring.desc_size field for the failed data ring. This oversight allows the hypervisor to continue referencing a stale or improperly initialized data ring structure, leading to undefined behavior and potential system crashes.
The technical flaw manifests as an invalid opcode exception and kernel BUG at net/core/skbuff.c:207, indicating that the system attempts to access invalid memory locations during packet processing. The call trace shows the error originates from vmxnet3_rq_rx_complete function, where the kernel panics while trying to process received packets. This occurs because the hypervisor continues to reference the data ring structure even though its memory allocation failed, resulting in a kernel panic and system instability. The issue directly corresponds to CWE-129, which describes improper validation of array indices, and represents a memory management error where allocated resources are not properly handled during failure conditions.
The operational impact of this vulnerability is significant for virtualized environments using VMware's vmxnet3 driver, particularly in production systems where network stability is critical. System administrators may experience unexpected kernel panics, service disruptions, and potential data loss during high network traffic periods. The vulnerability affects systems running Linux kernel versions that include the vmxnet3 driver, with the specific issue occurring when the driver fails to properly handle memory allocation errors in the receive data ring structures. This creates a persistent instability that can lead to complete system crashes, making it a critical security concern for virtualized infrastructure.
Mitigation strategies should focus on applying the kernel patch that sets rq->data_ring.desc_size to zero when memory allocation fails, effectively disabling the problematic data ring feature. System administrators should prioritize updating to kernel versions containing the fix, which is typically available through standard distribution channels. Additionally, monitoring systems should be configured to detect kernel panics and alert administrators to potential instability. Organizations using VMware virtualization platforms should also consider implementing network traffic monitoring to identify early signs of the vulnerability's impact, such as unusual packet processing delays or system restarts. The fix aligns with ATT&CK technique T1499.001, which covers network denial of service, as the vulnerability can cause system instability and service disruption through kernel panics.