CVE-2024-46765

Published Sep 18, 2024

Last updated 2 years ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ice: protect XDP configuration with a mutex The main threat to data consistency in ice_xdp() is a possible asynchronous PF reset. It can be triggered by a user or by TX timeout handler. XDP setup and PF reset code access the same resources in the following sections: * ice_vsi_close() in ice_prepare_for_reset() - already rtnl-locked * ice_vsi_rebuild() for the PF VSI - not protected * ice_vsi_open() - already rtnl-locked With an unfortunate timing, such accesses can result in a crash such as the one below: [ +1.999878] ice 0000:b1:00.0: Registered XDP mem model MEM_TYPE_XSK_BUFF_POOL on Rx ring 14 [ +2.002992] ice 0000:b1:00.0: Registered XDP mem model MEM_TYPE_XSK_BUFF_POOL on Rx ring 18 [Mar15 18:17] ice 0000:b1:00.0 ens801f0np0: NETDEV WATCHDOG: CPU: 38: transmit queue 14 timed out 80692736 ms [ +0.000093] ice 0000:b1:00.0 ens801f0np0: tx_timeout: VSI_num: 6, Q 14, NTC: 0x0, HW_HEAD: 0x0, NTU: 0x0, INT: 0x4000001 [ +0.000012] ice 0000:b1:00.0 ens801f0np0: tx_timeout recovery level 1, txqueue 14 [ +0.394718] ice 0000:b1:00.0: PTP reset successful [ +0.006184] BUG: kernel NULL pointer dereference, address: 0000000000000098 [ +0.000045] #PF: supervisor read access in kernel mode [ +0.000023] #PF: error_code(0x0000) - not-present page [ +0.000023] PGD 0 P4D 0 [ +0.000018] Oops: 0000 [#1] PREEMPT SMP NOPTI [ +0.000023] CPU: 38 PID: 7540 Comm: kworker/38:1 Not tainted 6.8.0-rc7 #1 [ +0.000031] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0014.082620210524 08/26/2021 [ +0.000036] Workqueue: ice ice_service_task [ice] [ +0.000183] RIP: 0010:ice_clean_tx_ring+0xa/0xd0 [ice] [...] [ +0.000013] Call Trace: [ +0.000016] <TASK> [ +0.000014] ? __die+0x1f/0x70 [ +0.000029] ? page_fault_oops+0x171/0x4f0 [ +0.000029] ? schedule+0x3b/0xd0 [ +0.000027] ? exc_page_fault+0x7b/0x180 [ +0.000022] ? asm_exc_page_fault+0x22/0x30 [ +0.000031] ? ice_clean_tx_ring+0xa/0xd0 [ice] [ +0.000194] ice_free_tx_ring+0xe/0x60 [ice] [ +0.000186] ice_destroy_xdp_rings+0x157/0x310 [ice] [ +0.000151] ice_vsi_decfg+0x53/0xe0 [ice] [ +0.000180] ice_vsi_rebuild+0x239/0x540 [ice] [ +0.000186] ice_vsi_rebuild_by_type+0x76/0x180 [ice] [ +0.000145] ice_rebuild+0x18c/0x840 [ice] [ +0.000145] ? delay_tsc+0x4a/0xc0 [ +0.000022] ? delay_tsc+0x92/0xc0 [ +0.000020] ice_do_reset+0x140/0x180 [ice] [ +0.000886] ice_service_task+0x404/0x1030 [ice] [ +0.000824] process_one_work+0x171/0x340 [ +0.000685] worker_thread+0x277/0x3a0 [ +0.000675] ? preempt_count_add+0x6a/0xa0 [ +0.000677] ? _raw_spin_lock_irqsave+0x23/0x50 [ +0.000679] ? __pfx_worker_thread+0x10/0x10 [ +0.000653] kthread+0xf0/0x120 [ +0.000635] ? __pfx_kthread+0x10/0x10 [ +0.000616] ret_from_fork+0x2d/0x50 [ +0.000612] ? __pfx_kthread+0x10/0x10 [ +0.000604] ret_from_fork_asm+0x1b/0x30 [ +0.000604] </TASK> The previous way of handling this through returning -EBUSY is not viable, particularly when destroying AF_XDP socket, because the kernel proceeds with removal anyway. There is plenty of code between those calls and there is no need to create a large critical section that covers all of them, same as there is no need to protect ice_vsi_rebuild() with rtnl_lock(). Add xdp_state_lock mutex to protect ice_vsi_rebuild() and ice_xdp(). Leaving unprotected sections in between would result in two states that have to be considered: 1. when the VSI is closed, but not yet rebuild 2. when VSI is already rebuild, but not yet open The latter case is actually already handled through !netif_running() case, we just need to adjust flag checking a little. The former one is not as trivial, because between ice_vsi_close() and ice_vsi_rebuild(), a lot of hardware interaction happens, this can make adding/deleting rings exit with an error. Luckily, VSI rebuild is pending and can apply new configuration for us in a managed fashion. Therefore, add an additional VSI state flag ICE_VSI_REBUILD_PENDING to indicate that ice_x ---truncated---
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
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