CVE-2023-53509
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-10-01

Last updated on: 2025-10-02

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: qed: allow sleep in qed_mcp_trace_dump() By default, qed_mcp_cmd_and_union() delays 10us at a time in a loop that can run 500K times, so calls to qed_mcp_nvm_rd_cmd() may block the current thread for over 5s. We observed thread scheduling delays over 700ms in production, with stacktraces pointing to this code as the culprit. qed_mcp_trace_dump() is called from ethtool, so sleeping is permitted. It already can sleep in qed_mcp_halt(), which calls qed_mcp_cmd(). Add a "can sleep" parameter to qed_find_nvram_image() and qed_nvram_read() so they can sleep during qed_mcp_trace_dump(). qed_mcp_trace_get_meta_info() and qed_mcp_trace_read_meta(), called only by qed_mcp_trace_dump(), allow these functions to sleep. I can't tell if the other caller (qed_grc_dump_mcp_hw_dump()) can sleep, so keep b_can_sleep set to false when it calls these functions. An example stacktrace from a custom warning we added to the kernel showing a thread that has not scheduled despite long needing resched: [ 2745.362925,17] ------------[ cut here ]------------ [ 2745.362941,17] WARNING: CPU: 23 PID: 5640 at arch/x86/kernel/irq.c:233 do_IRQ+0x15e/0x1a0() [ 2745.362946,17] Thread not rescheduled for 744 ms after irq 99 [ 2745.362956,17] Modules linked in: ... [ 2745.363339,17] CPU: 23 PID: 5640 Comm: lldpd Tainted: P O 4.4.182+ #202104120910+6d1da174272d.61x [ 2745.363343,17] Hardware name: FOXCONN MercuryB/Quicksilver Controller, BIOS H11P1N09 07/08/2020 [ 2745.363346,17] 0000000000000000 ffff885ec07c3ed8 ffffffff8131eb2f ffff885ec07c3f20 [ 2745.363358,17] ffffffff81d14f64 ffff885ec07c3f10 ffffffff81072ac2 ffff88be98ed0000 [ 2745.363369,17] 0000000000000063 0000000000000174 0000000000000074 0000000000000000 [ 2745.363379,17] Call Trace: [ 2745.363382,17] <IRQ> [<ffffffff8131eb2f>] dump_stack+0x8e/0xcf [ 2745.363393,17] [<ffffffff81072ac2>] warn_slowpath_common+0x82/0xc0 [ 2745.363398,17] [<ffffffff81072b4c>] warn_slowpath_fmt+0x4c/0x50 [ 2745.363404,17] [<ffffffff810d5a8e>] ? rcu_irq_exit+0xae/0xc0 [ 2745.363408,17] [<ffffffff817c99fe>] do_IRQ+0x15e/0x1a0 [ 2745.363413,17] [<ffffffff817c7ac9>] common_interrupt+0x89/0x89 [ 2745.363416,17] <EOI> [<ffffffff8132aa74>] ? delay_tsc+0x24/0x50 [ 2745.363425,17] [<ffffffff8132aa04>] __udelay+0x34/0x40 [ 2745.363457,17] [<ffffffffa04d45ff>] qed_mcp_cmd_and_union+0x36f/0x7d0 [qed] [ 2745.363473,17] [<ffffffffa04d5ced>] qed_mcp_nvm_rd_cmd+0x4d/0x90 [qed] [ 2745.363490,17] [<ffffffffa04e1dc7>] qed_mcp_trace_dump+0x4a7/0x630 [qed] [ 2745.363504,17] [<ffffffffa04e2556>] ? qed_fw_asserts_dump+0x1d6/0x1f0 [qed] [ 2745.363520,17] [<ffffffffa04e4ea7>] qed_dbg_mcp_trace_get_dump_buf_size+0x37/0x80 [qed] [ 2745.363536,17] [<ffffffffa04ea881>] qed_dbg_feature_size+0x61/0xa0 [qed] [ 2745.363551,17] [<ffffffffa04eb427>] qed_dbg_all_data_size+0x247/0x260 [qed] [ 2745.363560,17] [<ffffffffa0482c10>] qede_get_regs_len+0x30/0x40 [qede] [ 2745.363566,17] [<ffffffff816c9783>] ethtool_get_drvinfo+0xe3/0x190 [ 2745.363570,17] [<ffffffff816cc152>] dev_ethtool+0x1362/0x2140 [ 2745.363575,17] [<ffffffff8109bcc6>] ? finish_task_switch+0x76/0x260 [ 2745.363580,17] [<ffffffff817c2116>] ? __schedule+0x3c6/0x9d0 [ 2745.363585,17] [<ffffffff810dbd50>] ? hrtimer_start_range_ns+0x1d0/0x370 [ 2745.363589,17] [<ffffffff816c1e5b>] ? dev_get_by_name_rcu+0x6b/0x90 [ 2745.363594,17] [<ffffffff816de6a8>] dev_ioctl+0xe8/0x710 [ 2745.363599,17] [<ffffffff816a58a8>] sock_do_ioctl+0x48/0x60 [ 2745.363603,17] [<ffffffff816a5d87>] sock_ioctl+0x1c7/0x280 [ 2745.363608,17] [<ffffffff8111f393>] ? seccomp_phase1+0x83/0x220 [ 2745.363612,17] [<ffffffff811e3503>] do_vfs_ioctl+0x2b3/0x4e0 [ 2745.363616,17] [<ffffffff811e3771>] SyS_ioctl+0x41/0x70 [ 2745.363619,17] [<ffffffff817c6ffe>] entry_SYSCALL_64_fastpath+0x1e/0x79 [ 2745.363622,17] ---[ end trace f6954aa440266421 ]---
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2025-10-01
Last Modified
2025-10-02
Generated
2026-05-07
AI Q&A
2025-10-01
EPSS Evaluated
2026-05-05
NVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
linux linux_kernel 4.4.182
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

This vulnerability involves the Linux kernel's qed driver where a function called qed_mcp_cmd_and_union() delays execution in a loop that can block the current thread for over 5 seconds. This causes significant thread scheduling delays, observed to be over 700 milliseconds in production. The issue arises because the function does not allow sleeping during certain operations, leading to long blocking times. The fix involved allowing sleep in the qed_mcp_trace_dump() function and related calls, preventing the thread from being blocked for excessive time.


How can this vulnerability impact me? :

This vulnerability can cause significant delays in thread scheduling within the Linux kernel, potentially blocking threads for several seconds. This can degrade system performance, cause latency issues, and impact the responsiveness of applications relying on network drivers using the qed component. In production environments, this could lead to system slowdowns or degraded network performance.


How can this vulnerability be detected on my network or system? Can you suggest some commands?

This vulnerability can be detected by observing thread scheduling delays and analyzing kernel warnings related to threads not being rescheduled for unusually long times. Specifically, monitoring kernel logs for warnings similar to the provided stacktrace showing delays over 700ms and calls to qed_mcp_trace_dump() can indicate the presence of this issue. Commands to check kernel logs include: 'dmesg | grep -i warning' or 'journalctl -k | grep -i warning'. Additionally, monitoring for thread scheduling delays can be done by enabling custom kernel warnings or tracing tools that detect long scheduling delays.


What immediate steps should I take to mitigate this vulnerability?

Immediate mitigation involves updating the Linux kernel to a version where the qed_mcp_trace_dump() function has been fixed to allow sleeping properly, preventing long blocking delays. Since the issue is resolved by allowing sleep in certain functions, applying the vendor's kernel patch or upgrading to a fixed kernel release is the recommended step. There are no other direct mitigation steps mentioned.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart