Linux Kernel up to 5.15.26/5.16.12 iwlwifi debugfs_dir null pointer dereference

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.15.26/5.16.12 and classified as critical. The impacted element is the function debugfs_dir of the component iwlwifi. Executing a manipulation can lead to null pointer dereference. The identification of this vulnerability is CVE-2022-48918. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.15.26/5.16.12. It has been declared as critical. This vulnerability affects the function debugfs_dir of the component iwlwifi. 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: iwlwifi: mvm: check debugfs_dir ptr before use When "debugfs=off" is used on the kernel command line, iwiwifi's mvm module uses an invalid/unchecked debugfs_dir pointer and causes a BUG: BUG: kernel NULL pointer dereference, address: 000000000000004f #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 1 PID: 503 Comm: modprobe Tainted: G W 5.17.0-rc5 #7 Hardware name: Dell Inc. Inspiron 15 5510/076F7Y, BIOS 2.4.1 11/05/2021 RIP: 0010:iwl_mvm_dbgfs_register+0x692/0x700 [iwlmvm] Code: 69 a0 be 80 01 00 00 48 c7 c7 50 73 6a a0 e8 95 cf ee e0 48 8b 83 b0 1e 00 00 48 c7 c2 54 73 6a a0 be 64 00 00 00 48 8d 7d 8c 8b 48 50 e8 15 22 07 e1 48 8b 43 28 48 8d 55 8c 48 c7 c7 5f 73 RSP: 0018:ffffc90000a0ba68 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff88817d6e3328 RCX: ffff88817d6e3328 RDX: ffffffffa06a7354 RSI: 0000000000000064 RDI: ffffc90000a0ba6c RBP: ffffc90000a0bae0 R08: ffffffff824e4880 R09: ffffffffa069d620 R10: ffffc90000a0ba00 R11: ffffffffffffffff R12: 0000000000000000 R13: ffffc90000a0bb28 R14: ffff88817d6e3328 R15: ffff88817d6e3320 FS: 00007f64dd92d740(0000) GS:ffff88847f640000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000004f CR3: 000000016fc79001 CR4: 0000000000770ee0 PKRU: 55555554 Call Trace: ? iwl_mvm_mac_setup_register+0xbdc/0xda0 [iwlmvm] iwl_mvm_start_post_nvm+0x71/0x100 [iwlmvm] iwl_op_mode_mvm_start+0xab8/0xb30 [iwlmvm] _iwl_op_mode_start+0x6f/0xd0 [iwlwifi] iwl_opmode_register+0x6a/0xe0 [iwlwifi] ? 0xffffffffa0231000 iwl_mvm_init+0x35/0x1000 [iwlmvm] ? 0xffffffffa0231000 do_one_initcall+0x5a/0x1b0 ? kmem_cache_alloc+0x1e5/0x2f0 ? do_init_module+0x1e/0x220 do_init_module+0x48/0x220 load_module+0x2602/0x2bc0 ? __kernel_read+0x145/0x2e0 ? kernel_read_file+0x229/0x290 __do_sys_finit_module+0xc5/0x130 ? __do_sys_finit_module+0xc5/0x130 __x64_sys_finit_module+0x13/0x20 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f64dda564dd Code: 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 3d 01 f0 ff ff 73 01 c3 48 8b 0d 1b 29 0f 00 f7 d8 64 89 01 48 RSP: 002b:00007ffdba393f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f64dda564dd RDX: 0000000000000000 RSI: 00005575399e2ab2 RDI: 0000000000000001 RBP: 000055753a91c5e0 R08: 0000000000000000 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000246 R12: 00005575399e2ab2 R13: 000055753a91ceb0 R14: 0000000000000000 R15: 000055753a923018 Modules linked in: btintel(+) btmtk bluetooth vfat snd_hda_codec_hdmi fat snd_hda_codec_realtek snd_hda_codec_generic iwlmvm(+) snd_sof_pci_intel_tgl mac80211 snd_sof_intel_hda_common soundwire_intel soundwire_generic_allocation soundwire_cadence soundwire_bus snd_sof_intel_hda snd_sof_pci snd_sof snd_sof_xtensa_dsp snd_soc_hdac_hda snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi snd_soc_core btrfs snd_compress snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec raid6_pq iwlwifi snd_hda_core snd_pcm snd_timer snd soundcore cfg80211 intel_ish_ipc(+) thunderbolt rfkill intel_ishtp ucsi_acpi wmi i2c_hid_acpi i2c_hid evdev CR2: 000000000000004f ---[ end trace 0000000000000000 ]--- Check the debugfs_dir pointer for an error before using it. [change to make both conditional]

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2022-48918 since 08/21/2024. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

Upgrading to version 5.15.27 or 5.16.13 eliminates this vulnerability. Applying the patch 7de1ed755e1a/fe51975ff138/5a6248c0a223 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.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.16.0
• 5.16.1
• 5.16.2
• 5.16.3
• 5.16.4
• 5.16.5
• 5.16.6
• 5.16.7
• 5.16.8
• 5.16.9
• 5.16.10
• 5.16.11
• 5.16.12

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Threat Intelligenceinfo

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Entryinfo

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