Linux Kernel up to 6.13.7 debugfs_remove mana_port_debugfs null pointer dereference

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.13.7. Affected is the function debugfs_remove. The manipulation of the argument mana_port_debugfs results in null pointer dereference. This vulnerability is cataloged as CVE-2025-21953. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.13.7. Affected is the function debugfs_remove. The manipulation of the argument mana_port_debugfs with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as 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. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: mana: cleanup mana struct after debugfs_remove() When on a MANA VM hibernation is triggered, as part of hibernate_snapshot(), mana_gd_suspend() and mana_gd_resume() are called. If during this mana_gd_resume(), a failure occurs with HWC creation, mana_port_debugfs pointer does not get reinitialized and ends up pointing to older, cleaned-up dentry. Further in the hibernation path, as part of power_down(), mana_gd_shutdown() is triggered. This call, unaware of the failures in resume, tries to cleanup the already cleaned up mana_port_debugfs value and hits the following bug: [ 191.359296] mana 7870:00:00.0: Shutdown was called [ 191.359918] BUG: kernel NULL pointer dereference, address: 0000000000000098 [ 191.360584] #PF: supervisor write access in kernel mode [ 191.361125] #PF: error_code(0x0002) - not-present page [ 191.361727] PGD 1080ea067 P4D 0 [ 191.362172] Oops: Oops: 0002 [#1] SMP NOPTI [ 191.362606] CPU: 11 UID: 0 PID: 1674 Comm: bash Not tainted 6.14.0-rc5+ #2 [ 191.363292] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 191.364124] RIP: 0010:down_write+0x19/0x50 [ 191.364537] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 de cd ff ff 31 c0 ba 01 00 00 00 48 0f b1 13 75 16 65 48 8b 05 88 24 4c 6a 48 89 43 08 48 8b 5d [ 191.365867] RSP: 0000:ff45fbe0c1c037b8 EFLAGS: 00010246 [ 191.366350] RAX: 0000000000000000 RBX: 0000000000000098 RCX: ffffff8100000000 [ 191.366951] RDX: 0000000000000001 RSI: 0000000000000064 RDI: 0000000000000098 [ 191.367600] RBP: ff45fbe0c1c037c0 R08: 0000000000000000 R09: 0000000000000001 [ 191.368225] R10: ff45fbe0d2b01000 R11: 0000000000000008 R12: 0000000000000000 [ 191.368874] R13: 000000000000000b R14: ff43dc27509d67c0 R15: 0000000000000020 [ 191.369549] FS: 00007dbc5001e740(0000) GS:ff43dc663f380000(0000) knlGS:0000000000000000 [ 191.370213] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 191.370830] CR2: 0000000000000098 CR3: 0000000168e8e002 CR4: 0000000000b73ef0 [ 191.371557] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 191.372192] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 191.372906] Call Trace: [ 191.373262] [ 191.373621] ? show_regs+0x64/0x70 [ 191.374040] ? __die+0x24/0x70 [ 191.374468] ? page_fault_oops+0x290/0x5b0 [ 191.374875] ? do_user_addr_fault+0x448/0x800 [ 191.375357] ? exc_page_fault+0x7a/0x160 [ 191.375971] ? asm_exc_page_fault+0x27/0x30 [ 191.376416] ? down_write+0x19/0x50 [ 191.376832] ? down_write+0x12/0x50 [ 191.377232] simple_recursive_removal+0x4a/0x2a0 [ 191.377679] ? __pfx_remove_one+0x10/0x10 [ 191.378088] debugfs_remove+0x44/0x70 [ 191.378530] mana_detach+0x17c/0x4f0 [ 191.378950] ? __flush_work+0x1e2/0x3b0 [ 191.379362] ? __cond_resched+0x1a/0x50 [ 191.379787] mana_remove+0xf2/0x1a0 [ 191.380193] mana_gd_shutdown+0x3b/0x70 [ 191.380642] pci_device_shutdown+0x3a/0x80 [ 191.381063] device_shutdown+0x13e/0x230 [ 191.381480] kernel_power_off+0x35/0x80 [ 191.381890] hibernate+0x3c6/0x470 [ 191.382312] state_store+0xcb/0xd0 [ 191.382734] kobj_attr_store+0x12/0x30 [ 191.383211] sysfs_kf_write+0x3e/0x50 [ 191.383640] kernfs_fop_write_iter+0x140/0x1d0 [ 191.384106] vfs_write+0x271/0x440 [ 191.384521] ksys_write+0x72/0xf0 [ 191.384924] __x64_sys_write+0x19/0x20 [ 191.385313] x64_sys_call+0x2b0/0x20b0 [ 191.385736] do_syscall_64+0x79/0x150 [ 191.386146] ? __mod_memcg_lruvec_state+0xe7/0x240 [ 191.386676] ? __lruvec_stat_mod_folio+0x79/0xb0 [ 191.387124] ? __pfx_lru_add+0x10/0x10 [ 191.387515] ? queued_spin_unlock+0x9/0x10 [ 191.387937] ? do_anonymous_page+0x33c/0xa00 [ 191.388374] ? __handle_mm_fault+0xcf3/0x1210 [ 191.388805] ? __count_memcg_events+0xbe/0x180 [ 191.389235] ? handle_mm_fault+0xae/0x300 [ 19 ---truncated---

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-21953 since 12/29/2024. The exploitability is told to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 235464 (Ubuntu 24.04 LTS : Linux kernel (Azure) vulnerabilities (USN-7500-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.13.8 eliminates this vulnerability. Applying the patch a1466112fb6e819261272ad75e7db750a43b78bf/3e64bb2ae7d9f2b3a8259d4d6b86ed1984d5460a 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 (235464) and CERT Bund (WID-SEC-2025-0683). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• Dell Avamar
• Open Source Linux Kernel
• SolarWinds Security Event Manager
• Dell NetWorker
• Dell Secure Connect Gateway
• IBM Security Verify Access

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.13.0
• 6.13.1
• 6.13.2
• 6.13.3
• 6.13.4
• 6.13.5
• 6.13.6
• 6.13.7

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion