CVE-2022-48811

Published Jul 16, 2024

Last updated 9 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ibmvnic: don't release napi in __ibmvnic_open() If __ibmvnic_open() encounters an error such as when setting link state, it calls release_resources() which frees the napi structures needlessly. Instead, have __ibmvnic_open() only clean up the work it did so far (i.e. disable napi and irqs) and leave the rest to the callers. If caller of __ibmvnic_open() is ibmvnic_open(), it should release the resources immediately. If the caller is do_reset() or do_hard_reset(), they will release the resources on the next reset. This fixes following crash that occurred when running the drmgr command several times to add/remove a vnic interface: [102056] ibmvnic 30000003 env3: Disabling rx_scrq[6] irq [102056] ibmvnic 30000003 env3: Disabling rx_scrq[7] irq [102056] ibmvnic 30000003 env3: Replenished 8 pools Kernel attempted to read user page (10) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000010 Faulting instruction address: 0xc000000000a3c840 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries ... CPU: 9 PID: 102056 Comm: kworker/9:2 Kdump: loaded Not tainted 5.16.0-rc5-autotest-g6441998e2e37 #1 Workqueue: events_long __ibmvnic_reset [ibmvnic] NIP: c000000000a3c840 LR: c0080000029b5378 CTR: c000000000a3c820 REGS: c0000000548e37e0 TRAP: 0300 Not tainted (5.16.0-rc5-autotest-g6441998e2e37) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 28248484 XER: 00000004 CFAR: c0080000029bdd24 DAR: 0000000000000010 DSISR: 40000000 IRQMASK: 0 GPR00: c0080000029b55d0 c0000000548e3a80 c0000000028f0200 0000000000000000 ... NIP [c000000000a3c840] napi_enable+0x20/0xc0 LR [c0080000029b5378] __ibmvnic_open+0xf0/0x430 [ibmvnic] Call Trace: [c0000000548e3a80] [0000000000000006] 0x6 (unreliable) [c0000000548e3ab0] [c0080000029b55d0] __ibmvnic_open+0x348/0x430 [ibmvnic] [c0000000548e3b40] [c0080000029bcc28] __ibmvnic_reset+0x500/0xdf0 [ibmvnic] [c0000000548e3c60] [c000000000176228] process_one_work+0x288/0x570 [c0000000548e3d00] [c000000000176588] worker_thread+0x78/0x660 [c0000000548e3da0] [c0000000001822f0] kthread+0x1c0/0x1d0 [c0000000548e3e10] [c00000000000cf64] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 7d2948f8 792307e0 4e800020 60000000 3c4c01eb 384239e0 f821ffd1 39430010 38a0fff6 e92d1100 f9210028 39200000 <e9030010> f9010020 60420000 e9210020 ---[ end trace 5f8033b08fd27706 ]---
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