Description

In the Linux kernel, the following vulnerability has been resolved: kdb: Fix buffer overflow during tab-complete Currently, when the user attempts symbol completion with the Tab key, kdb will use strncpy() to insert the completed symbol into the command buffer. Unfortunately it passes the size of the source buffer rather than the destination to strncpy() with predictably horrible results. Most obviously if the command buffer is already full but cp, the cursor position, is in the middle of the buffer, then we will write past the end of the supplied buffer. Fix this by replacing the dubious strncpy() calls with memmove()/memcpy() calls plus explicit boundary checks to make sure we have enough space before we start moving characters around.

Severity HIGH

CVSS Score 7.8

CVSS Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWE CWE-120

Public Exploit ✅ No

Source NVD

Published 2024-07-05

Updated 2026-06-02

Modified 2024-11-21

Fix URL https://git.kernel.org/stable/c/107e825cc448b7834b31e8b1b3cf0f57426d46d5

Software	From version	Fixed in
linux-kernel	6.9	6.9.5