CVE-2024-35927

Published May 19, 2024

Last updated 9 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: drm: Check output polling initialized before disabling In drm_kms_helper_poll_disable() check if output polling support is initialized before disabling polling. If not flag this as a warning. Additionally in drm_mode_config_helper_suspend() and drm_mode_config_helper_resume() calls, that re the callers of these functions, avoid invoking them if polling is not initialized. For drivers like hyperv-drm, that do not initialize connector polling, if suspend is called without this check, it leads to suspend failure with following stack [ 770.719392] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. [ 770.720592] printk: Suspending console(s) (use no_console_suspend to debug) [ 770.948823] ------------[ cut here ]------------ [ 770.948824] WARNING: CPU: 1 PID: 17197 at kernel/workqueue.c:3162 __flush_work.isra.0+0x212/0x230 [ 770.948831] Modules linked in: rfkill nft_counter xt_conntrack xt_owner udf nft_compat crc_itu_t nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink vfat fat mlx5_ib ib_uverbs ib_core mlx5_core intel_rapl_msr intel_rapl_common kvm_amd ccp mlxfw kvm psample hyperv_drm tls drm_shmem_helper drm_kms_helper irqbypass pcspkr syscopyarea sysfillrect sysimgblt hv_balloon hv_utils joydev drm fuse xfs libcrc32c pci_hyperv pci_hyperv_intf sr_mod sd_mod cdrom t10_pi sg hv_storvsc scsi_transport_fc hv_netvsc serio_raw hyperv_keyboard hid_hyperv crct10dif_pclmul crc32_pclmul crc32c_intel hv_vmbus ghash_clmulni_intel dm_mirror dm_region_hash dm_log dm_mod [ 770.948863] CPU: 1 PID: 17197 Comm: systemd-sleep Not tainted 5.14.0-362.2.1.el9_3.x86_64 #1 [ 770.948865] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 770.948866] RIP: 0010:__flush_work.isra.0+0x212/0x230 [ 770.948869] Code: 8b 4d 00 4c 8b 45 08 89 ca 48 c1 e9 04 83 e2 08 83 e1 0f 83 ca 02 89 c8 48 0f ba 6d 00 03 e9 25 ff ff ff 0f 0b e9 4e ff ff ff <0f> 0b 45 31 ed e9 44 ff ff ff e8 8f 89 b2 00 66 66 2e 0f 1f 84 00 [ 770.948870] RSP: 0018:ffffaf4ac213fb10 EFLAGS: 00010246 [ 770.948871] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8c992857 [ 770.948872] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff9aad82b00330 [ 770.948873] RBP: ffff9aad82b00330 R08: 0000000000000000 R09: ffff9aad87ee3d10 [ 770.948874] R10: 0000000000000200 R11: 0000000000000000 R12: ffff9aad82b00330 [ 770.948874] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 770.948875] FS: 00007ff1b2f6bb40(0000) GS:ffff9aaf37d00000(0000) knlGS:0000000000000000 [ 770.948878] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 770.948878] CR2: 0000555f345cb666 CR3: 00000001462dc005 CR4: 0000000000370ee0 [ 770.948879] Call Trace: [ 770.948880] <TASK> [ 770.948881] ? show_trace_log_lvl+0x1c4/0x2df [ 770.948884] ? show_trace_log_lvl+0x1c4/0x2df [ 770.948886] ? __cancel_work_timer+0x103/0x190 [ 770.948887] ? __flush_work.isra.0+0x212/0x230 [ 770.948889] ? __warn+0x81/0x110 [ 770.948891] ? __flush_work.isra.0+0x212/0x230 [ 770.948892] ? report_bug+0x10a/0x140 [ 770.948895] ? handle_bug+0x3c/0x70 [ 770.948898] ? exc_invalid_op+0x14/0x70 [ 770.948899] ? asm_exc_invalid_op+0x16/0x20 [ 770.948903] ? __flush_work.isra.0+0x212/0x230 [ 770.948905] __cancel_work_timer+0x103/0x190 [ 770.948907] ? _raw_spin_unlock_irqrestore+0xa/0x30 [ 770.948910] drm_kms_helper_poll_disable+0x1e/0x40 [drm_kms_helper] [ 770.948923] drm_mode_config_helper_suspend+0x1c/0x80 [drm_kms_helper] [ 770.948933] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus] [ 770.948942] hyperv_vmbus_suspend+0x17/0x40 [hyperv_drm] [ 770.948944] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus] [ 770.948951] dpm_run_callback+0x4c/0x140 [ 770.948954] __device_suspend_noir ---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
NVD-CWE-noinfo

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