QgCg1Xr7w+GBMJlkNxYTHvUerI+0fo8R5RoDannySRgAAIiY2nJSyVo8Zp eyO7Z29W1H72w/GYSJsMmcM2eW20wDZBunZ579as++DMzTCEGRZ/yzhb+UDX6Q== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1765203122; a=rsa-sha256; cv=none; b=A6CFR65UtYMSTAeDlVi/8W5X8RzKze9UlndQQy6Q59W+Qh5nr8iFq3Ks4KGl/3aZ0n601n ggGrn2oQNMxXNcm0dixrI73gARPsWFS/ah7fK2JMTXXc0QH+x3cHJKtbMoJqMlaRVVM5IF CCZ5GbwyQ6TybChOkwZWE23/IHpeTPx9bAMxx+vb5zbGvnEt6/Op9RhRJgmorBjJM8r0gf HSL3NVGMbSGnCI7koc4vftsOx64LFl55utO2H9CU4P60NX+70HIqMWHAKv6nArhXiZidJg sI6dEN2vJGMdVYUcJ9cZnCfTytWayNaLgxfiyZ6Bs5SWidjQ3sqVk0TkI//LlQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4dQ3nt0csfz1QS for ; Mon, 08 Dec 2025 14:12:02 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 2fea8 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Mon, 08 Dec 2025 14:12:02 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 73586fcea630 - main - libkern: Avoid a one-byte OOB access in strndup() List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 73586fcea630c2c4fb83e966920c039aee8a5fc9 Auto-Submitted: auto-generated Date: Mon, 08 Dec 2025 14:12:02 +0000 Message-Id: <6936dcb2.2fea8.5fcd778@gitrepo.freebsd.org> The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=73586fcea630c2c4fb83e966920c039aee8a5fc9 commit 73586fcea630c2c4fb83e966920c039aee8a5fc9 Author: Mark Johnston AuthorDate: 2025-12-08 14:08:22 +0000 Commit: Mark Johnston CommitDate: 2025-12-08 14:08:22 +0000 libkern: Avoid a one-byte OOB access in strndup() If the length of the string is maxlen, we would end up copying maxlen+1 bytes, which violates the contract of the function. The result is the same since that extra byte is overwritten. Reported by: Kevin Day Reviewed by: imp, kib MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D54093 --- sys/libkern/strndup.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/sys/libkern/strndup.c b/sys/libkern/strndup.c index 75b33339e1c7..1fbcfd28cae4 100644 --- a/sys/libkern/strndup.c +++ b/sys/libkern/strndup.c @@ -40,9 +40,9 @@ strndup(const char *string, size_t maxlen, struct malloc_type *type) size_t len; char *copy; - len = strnlen(string, maxlen) + 1; - copy = malloc(len, type, M_WAITOK); + len = strnlen(string, maxlen); + copy = malloc(len + 1, type, M_WAITOK); memcpy(copy, string, len); - copy[len - 1] = '\0'; + copy[len] = '\0'; return (copy); }