CVE-2022-49096

Published Feb 26, 2025

Last updated 8 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: net: sfc: add missing xdp queue reinitialization After rx/tx ring buffer size is changed, kernel panic occurs when it acts XDP_TX or XDP_REDIRECT. When tx/rx ring buffer size is changed(ethtool -G), sfc driver reallocates and reinitializes rx and tx queues and their buffer (tx_queue->buffer). But it misses reinitializing xdp queues(efx->xdp_tx_queues). So, while it is acting XDP_TX or XDP_REDIRECT, it uses the uninitialized tx_queue->buffer. A new function efx_set_xdp_channels() is separated from efx_set_channels() to handle only xdp queues. Splat looks like: BUG: kernel NULL pointer dereference, address: 000000000000002a #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#4] PREEMPT SMP NOPTI RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G D 5.17.0+ #55 e8beeee8289528f11357029357cf Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80 RSP: 0018:ffff92f121e45c60 EFLAGS: 00010297 RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc] RAX: 0000000000000040 RBX: ffff92ea506895c0 RCX: ffffffffc0330870 RDX: 0000000000000001 RSI: 00000001139b10ce RDI: ffff92ea506895c0 RBP: ffffffffc0358a80 R08: 00000001139b110d R09: 0000000000000000 R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040 R13: 0000000000000018 R14: 00000001139b10ce R15: ffff92ea506895c0 FS: 0000000000000000(0000) GS:ffff92f121ec0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80 CR2: 000000000000002a CR3: 00000003e6810004 CR4: 00000000007706e0 RSP: 0018:ffff92f121e85c60 EFLAGS: 00010297 PKRU: 55555554 RAX: 0000000000000040 RBX: ffff92ea50689700 RCX: ffffffffc0330870 RDX: 0000000000000001 RSI: 00000001145a90ce RDI: ffff92ea50689700 RBP: ffffffffc0358a80 R08: 00000001145a910d R09: 0000000000000000 R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040 R13: 0000000000000018 R14: 00000001145a90ce R15: ffff92ea50689700 FS: 0000000000000000(0000) GS:ffff92f121e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000002a CR3: 00000003e6810005 CR4: 00000000007706e0 PKRU: 55555554 Call Trace: <IRQ> efx_xdp_tx_buffers+0x12b/0x3d0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] __efx_rx_packet+0x5c3/0x930 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] efx_rx_packet+0x28c/0x2e0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] efx_ef10_ev_process+0x5f8/0xf40 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] ? enqueue_task_fair+0x95/0x550 efx_poll+0xc4/0x360 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
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
134c704f-9b21-4f2e-91b3-4a467353bcc0
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