CVE-2025-38224

Published Jul 4, 2025

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: can: kvaser_pciefd: refine error prone echo_skb_max handling logic echo_skb_max should define the supported upper limit of echo_skb[] allocated inside the netdevice's priv. The corresponding size value provided by this driver to alloc_candev() is KVASER_PCIEFD_CAN_TX_MAX_COUNT which is 17. But later echo_skb_max is rounded up to the nearest power of two (for the max case, that would be 32) and the tx/ack indices calculated further during tx/rx may exceed the upper array boundary. Kasan reported this for the ack case inside kvaser_pciefd_handle_ack_packet(), though the xmit function has actually caught the same thing earlier. BUG: KASAN: slab-out-of-bounds in kvaser_pciefd_handle_ack_packet+0x2d7/0x92a drivers/net/can/kvaser_pciefd.c:1528 Read of size 8 at addr ffff888105e4f078 by task swapper/4/0 CPU: 4 UID: 0 PID: 0 Comm: swapper/4 Not tainted 6.15.0 #12 PREEMPT(voluntary) Call Trace: <IRQ> dump_stack_lvl lib/dump_stack.c:122 print_report mm/kasan/report.c:521 kasan_report mm/kasan/report.c:634 kvaser_pciefd_handle_ack_packet drivers/net/can/kvaser_pciefd.c:1528 kvaser_pciefd_read_packet drivers/net/can/kvaser_pciefd.c:1605 kvaser_pciefd_read_buffer drivers/net/can/kvaser_pciefd.c:1656 kvaser_pciefd_receive_irq drivers/net/can/kvaser_pciefd.c:1684 kvaser_pciefd_irq_handler drivers/net/can/kvaser_pciefd.c:1733 __handle_irq_event_percpu kernel/irq/handle.c:158 handle_irq_event kernel/irq/handle.c:210 handle_edge_irq kernel/irq/chip.c:833 __common_interrupt arch/x86/kernel/irq.c:296 common_interrupt arch/x86/kernel/irq.c:286 </IRQ> Tx max count definitely matters for kvaser_pciefd_tx_avail(), but for seq numbers' generation that's not the case - we're free to calculate them as would be more convenient, not taking tx max count into account. The only downside is that the size of echo_skb[] should correspond to the max seq number (not tx max count), so in some situations a bit more memory would be consumed than could be. Thus make the size of the underlying echo_skb[] sufficient for the rounded max tx value. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.1
Impact score
5.2
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-125

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