Linux Kernel up to 6.12.55/6.17.5 mlx5e_detach_netdev null pointer dereference

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.55/6.17.5. Affected by this issue is the function mlx5e_detach_netdev. This manipulation causes null pointer dereference. This vulnerability is handled as CVE-2025-40238. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.12.55/6.17.5 and classified as critical. Affected by this vulnerability is the function mlx5e_detach_netdev. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix IPsec cleanup over MPV device When we do mlx5e_detach_netdev() we eventually disable blocking events notifier, among those events are IPsec MPV events from IB to core. So before disabling those blocking events, make sure to also unregister the devcom device and mark all this device operations as complete, in order to prevent the other device from using invalid netdev during future devcom events which could cause the trace below. BUG: kernel NULL pointer dereference, address: 0000000000000010 PGD 146427067 P4D 146427067 PUD 146488067 PMD 0 Oops: Oops: 0000 [#1] SMP CPU: 1 UID: 0 PID: 7735 Comm: devlink Tainted: GW 6.12.0-rc6_for_upstream_min_debug_2024_11_08_00_46 #1 Tainted: [W]=WARN Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:mlx5_devcom_comp_set_ready+0x5/0x40 [mlx5_core] Code: 00 01 48 83 05 23 32 1e 00 01 41 b8 ed ff ff ff e9 60 ff ff ff 48 83 05 00 32 1e 00 01 eb e3 66 0f 1f 44 00 00 0f 1f 44 00 00 <48> 8b 47 10 48 83 05 5f 32 1e 00 01 48 8b 50 40 48 85 d2 74 05 40 RSP: 0018:ffff88811a5c35f8 EFLAGS: 00010206 RAX: ffff888106e8ab80 RBX: ffff888107d7e200 RCX: ffff88810d6f0a00 RDX: ffff88810d6f0a00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff88811a17e620 R08: 0000000000000040 R09: 0000000000000000 R10: ffff88811a5c3618 R11: 0000000de85d51bd R12: ffff88811a17e600 R13: ffff88810d6f0a00 R14: 0000000000000000 R15: ffff8881034bda80 FS: 00007f27bdf89180(0000) GS:ffff88852c880000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 000000010f159005 CR4: 0000000000372eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __die+0x20/0x60 ? page_fault_oops+0x150/0x3e0 ? exc_page_fault+0x74/0x130 ? asm_exc_page_fault+0x22/0x30 ? mlx5_devcom_comp_set_ready+0x5/0x40 [mlx5_core] mlx5e_devcom_event_mpv+0x42/0x60 [mlx5_core] mlx5_devcom_send_event+0x8c/0x170 [mlx5_core] blocking_event+0x17b/0x230 [mlx5_core] notifier_call_chain+0x35/0xa0 blocking_notifier_call_chain+0x3d/0x60 mlx5_blocking_notifier_call_chain+0x22/0x30 [mlx5_core] mlx5_core_mp_event_replay+0x12/0x20 [mlx5_core] mlx5_ib_bind_slave_port+0x228/0x2c0 [mlx5_ib] mlx5_ib_stage_init_init+0x664/0x9d0 [mlx5_ib] ? idr_alloc_cyclic+0x50/0xb0 ? __kmalloc_cache_noprof+0x167/0x340 ? __kmalloc_noprof+0x1a7/0x430 __mlx5_ib_add+0x34/0xd0 [mlx5_ib] mlx5r_probe+0xe9/0x310 [mlx5_ib] ? kernfs_add_one+0x107/0x150 ? __mlx5_ib_add+0xd0/0xd0 [mlx5_ib] auxiliary_bus_probe+0x3e/0x90 really_probe+0xc5/0x3a0 ? driver_probe_device+0x90/0x90 __driver_probe_device+0x80/0x160 driver_probe_device+0x1e/0x90 __device_attach_driver+0x7d/0x100 bus_for_each_drv+0x80/0xd0 __device_attach+0xbc/0x1f0 bus_probe_device+0x86/0xa0 device_add+0x62d/0x830 __auxiliary_device_add+0x3b/0xa0 ? auxiliary_device_init+0x41/0x90 add_adev+0xd1/0x150 [mlx5_core] mlx5_rescan_drivers_locked+0x21c/0x300 [mlx5_core] esw_mode_change+0x6c/0xc0 [mlx5_core] mlx5_devlink_eswitch_mode_set+0x21e/0x640 [mlx5_core] devlink_nl_eswitch_set_doit+0x60/0xe0 genl_family_rcv_msg_doit+0xd0/0x120 genl_rcv_msg+0x180/0x2b0 ? devlink_get_from_attrs_lock+0x170/0x170 ? devlink_nl_eswitch_get_doit+0x290/0x290 ? devlink_nl_pre_doit_port_optional+0x50/0x50 ? genl_family_rcv_msg_dumpit+0xf0/0xf0 netlink_rcv_skb+0x54/0x100 genl_rcv+0x24/0x40 netlink_unicast+0x1fc/0x2d0 netlink_sendmsg+0x1e4/0x410 __sock_sendmsg+0x38/0x60 ? sockfd_lookup_light+0x12/0x60 __sys_sendto+0x105/0x160 ? __sys_recvmsg+0x4e/0x90 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x4c/0x100 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f27bc91b13a Code: bb 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 fa 96 2c 00 45 89 c9 4c 63 d1 48 63 ff 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff ---truncated---

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-40238 since 04/16/2025. The exploitation appears to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 277592 (Linux Distros Unpatched Vulnerability : CVE-2025-40238), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.56 or 6.17.6 eliminates this vulnerability. Applying the patch 7e212cebc863c2c7a82f480446cd731721451691/8956686d398eca6d324d2d164f9d2a281175a3a1/664f76be38a18c61151d0ef248c7e2f3afb4f3c7 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (277592) and CERT Bund (WID-SEC-2025-2747). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Microsoft Azure Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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