Bugzilla – Bug 1227445
VUL-0: CVE-2024-39480: kernel: kdb: Fix buffer overflow during tab-complete
Last modified: 2024-07-08 04:34:20 UTC
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. References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-39480 https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-39480.mbox https://git.kernel.org/stable/c/fb824a99e148ff272a53d71d84122728b5f00992 https://git.kernel.org/stable/c/ddd2972d8e2dee3b33e8121669d55def59f0be8a https://git.kernel.org/stable/c/cfdc2fa4db57503bc6d3817240547c8ddc55fa96 https://git.kernel.org/stable/c/f636a40834d22e5e3fc748f060211879c056cd33 https://git.kernel.org/stable/c/33d9c814652b971461d1e30bead6792851c209e7 https://git.kernel.org/stable/c/107e825cc448b7834b31e8b1b3cf0f57426d46d5 https://git.kernel.org/stable/c/f694da720dcf795dc3eb97bf76d220213f76aaa7 https://git.kernel.org/stable/c/e9730744bf3af04cda23799029342aa3cddbc454 https://www.cve.org/CVERecord?id=CVE-2024-39480