CVE-2024-46755

Published Sep 18, 2024

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: wifi: mwifiex: Do not return unused priv in mwifiex_get_priv_by_id() mwifiex_get_priv_by_id() returns the priv pointer corresponding to the bss_num and bss_type, but without checking if the priv is actually currently in use. Unused priv pointers do not have a wiphy attached to them which can lead to NULL pointer dereferences further down the callstack. Fix this by returning only used priv pointers which have priv->bss_mode set to something else than NL80211_IFTYPE_UNSPECIFIED. Said NULL pointer dereference happened when an Accesspoint was started with wpa_supplicant -i mlan0 with this config: network={ ssid="somessid" mode=2 frequency=2412 key_mgmt=WPA-PSK WPA-PSK-SHA256 proto=RSN group=CCMP pairwise=CCMP psk="12345678" } When waiting for the AP to be established, interrupting wpa_supplicant with <ctrl-c> and starting it again this happens: | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000140 | Mem abort info: | ESR = 0x0000000096000004 | EC = 0x25: DABT (current EL), IL = 32 bits | SET = 0, FnV = 0 | EA = 0, S1PTW = 0 | FSC = 0x04: level 0 translation fault | Data abort info: | ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 | CM = 0, WnR = 0, TnD = 0, TagAccess = 0 | GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 | user pgtable: 4k pages, 48-bit VAs, pgdp=0000000046d96000 | [0000000000000140] pgd=0000000000000000, p4d=0000000000000000 | Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP | Modules linked in: caam_jr caamhash_desc spidev caamalg_desc crypto_engine authenc libdes mwifiex_sdio +mwifiex crct10dif_ce cdc_acm onboard_usb_hub fsl_imx8_ddr_perf imx8m_ddrc rtc_ds1307 lm75 rtc_snvs +imx_sdma caam imx8mm_thermal spi_imx error imx_cpufreq_dt fuse ip_tables x_tables ipv6 | CPU: 0 PID: 8 Comm: kworker/0:1 Not tainted 6.9.0-00007-g937242013fce-dirty #18 | Hardware name: somemachine (DT) | Workqueue: events sdio_irq_work | pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : mwifiex_get_cfp+0xd8/0x15c [mwifiex] | lr : mwifiex_get_cfp+0x34/0x15c [mwifiex] | sp : ffff8000818b3a70 | x29: ffff8000818b3a70 x28: ffff000006bfd8a5 x27: 0000000000000004 | x26: 000000000000002c x25: 0000000000001511 x24: 0000000002e86bc9 | x23: ffff000006bfd996 x22: 0000000000000004 x21: ffff000007bec000 | x20: 000000000000002c x19: 0000000000000000 x18: 0000000000000000 | x17: 000000040044ffff x16: 00500072b5503510 x15: ccc283740681e517 | x14: 0201000101006d15 x13: 0000000002e8ff43 x12: 002c01000000ffb1 | x11: 0100000000000000 x10: 02e8ff43002c0100 x9 : 0000ffb100100157 | x8 : ffff000003d20000 x7 : 00000000000002f1 x6 : 00000000ffffe124 | x5 : 0000000000000001 x4 : 0000000000000003 x3 : 0000000000000000 | x2 : 0000000000000000 x1 : 0001000000011001 x0 : 0000000000000000 | Call trace: | mwifiex_get_cfp+0xd8/0x15c [mwifiex] | mwifiex_parse_single_response_buf+0x1d0/0x504 [mwifiex] | mwifiex_handle_event_ext_scan_report+0x19c/0x2f8 [mwifiex] | mwifiex_process_sta_event+0x298/0xf0c [mwifiex] | mwifiex_process_event+0x110/0x238 [mwifiex] | mwifiex_main_process+0x428/0xa44 [mwifiex] | mwifiex_sdio_interrupt+0x64/0x12c [mwifiex_sdio] | process_sdio_pending_irqs+0x64/0x1b8 | sdio_irq_work+0x4c/0x7c | process_one_work+0x148/0x2a0 | worker_thread+0x2fc/0x40c | kthread+0x110/0x114 | ret_from_fork+0x10/0x20 | Code: a94153f3 a8c37bfd d50323bf d65f03c0 (f940a000) | ---[ end trace 0000000000000000 ]---
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-476

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: coresight: tmc-etr: Fix race condition between sysfs and perf mode When trying to run perf and sysfs mode simultaneously, the WARN_ON() in tmc_etr_enable_hw() is triggered sometimes: WARNING: CPU: 42 PID: 3911571 at drivers/hwtracing/coresight/coresight-tmc-etr.c:1060 tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] [..snip..] Call trace: tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] (P) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] (L) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] coresight_enable_path+0x1c8/0x218 [coresight] coresight_enable_sysfs+0xa4/0x228 [coresight] enable_source_store+0x58/0xa8 [coresight] dev_attr_store+0x20/0x40 sysfs_kf_write+0x4c/0x68 kernfs_fop_write_iter+0x120/0x1b8 vfs_write+0x2c8/0x388 ksys_write+0x74/0x108 __arm64_sys_write+0x24/0x38 el0_svc_common.constprop.0+0x64/0x148 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x130 el0t_64_sync_handler+0xc8/0xd0 el0t_64_sync+0x1ac/0x1b0 ---[ end trace 0000000000000000 ]--- Since the enablement of sysfs mode is separeted into two critical regions, one for sysfs buffer allocation and another for hardware enablement, it's possible to race with the perf mode. Fix this by double check whether the perf mode's been used before enabling the hardware in sysfs mode. mode: [sysfs mode] [perf mode] tmc_etr_get_sysfs_buffer() spin_lock(&drvdata->spinlock) [sysfs buffer allocation] spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() drvdata->etr_buf = etr_perf->etr_buf spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() WARN_ON(drvdata->etr_buf) // WARN sicne etr_buf initialized at the perf side spin_unlock(&drvdata->spinlock) With this fix, we retain the check for CS_MODE_PERF in get_etr_sysfs_buf. This ensures we verify whether the perf mode's already running before we actually allocate the buffer. Then we can save the time of allocating/freeing the sysfs buffer if race with the perf mode.CVE-2026-46272