CVE-2024-44933

Published Aug 26, 2024

Last updated 2 years ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: bnxt_en : Fix memory out-of-bounds in bnxt_fill_hw_rss_tbl() A recent commit has modified the code in __bnxt_reserve_rings() to set the default RSS indirection table to default only when the number of RX rings is changing. While this works for newer firmware that requires RX ring reservations, it causes the regression on older firmware not requiring RX ring resrvations (BNXT_NEW_RM() returns false). With older firmware, RX ring reservations are not required and so hw_resc->resv_rx_rings is not always set to the proper value. The comparison: if (old_rx_rings != bp->hw_resc.resv_rx_rings) in __bnxt_reserve_rings() may be false even when the RX rings are changing. This will cause __bnxt_reserve_rings() to skip setting the default RSS indirection table to default to match the current number of RX rings. This may later cause bnxt_fill_hw_rss_tbl() to use an out-of-range index. We already have bnxt_check_rss_tbl_no_rmgr() to handle exactly this scenario. We just need to move it up in bnxt_need_reserve_rings() to be called unconditionally when using older firmware. Without the fix, if the TX rings are changing, we'll skip the bnxt_check_rss_tbl_no_rmgr() call and __bnxt_reserve_rings() may also skip the bnxt_set_dflt_rss_indir_tbl() call for the reason explained in the last paragraph. Without setting the default RSS indirection table to default, it causes the regression: BUG: KASAN: slab-out-of-bounds in __bnxt_hwrm_vnic_set_rss+0xb79/0xe40 Read of size 2 at addr ffff8881c5809618 by task ethtool/31525 Call Trace: __bnxt_hwrm_vnic_set_rss+0xb79/0xe40 bnxt_hwrm_vnic_rss_cfg_p5+0xf7/0x460 __bnxt_setup_vnic_p5+0x12e/0x270 __bnxt_open_nic+0x2262/0x2f30 bnxt_open_nic+0x5d/0xf0 ethnl_set_channels+0x5d4/0xb30 ethnl_default_set_doit+0x2f1/0x620
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-787

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