From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794064488; b=qbc5neUaxZ67G91xDSdtdKlCikqUK8/FetixreNTfvVbgeIpf6hTbJNY87bVx0y6Cs/3 cXAmcKMQQOFM2ftIFDOBxLs2lKxgiDFoPgF6enbauhcGdHBjzWOaBps+txkqrAs9L1drb cW1MR6YSz0I1JbCtyJs5zDEvkrVN5XPeheoitrDd39D6AUCB0sTxLGOIN/BmHvnOYZPtn q2vtKy15fhUCEge4tBGjYxQJsCE3dQam7WnXjTyo24UPfAvwetTCqdnsF2ALouJfZi6zk vChOxG1gRFfRLq5oVuTQJtQ7iK0Gld+g9JTcOr3JyIeQcfBW8molP58+39hpBteGRkA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794064488; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=28wqrs0w+f1Nw7Z8WPcti7aWS+wKg6ubG9fxeQsjbX0=; b=E98tE1Vjwxa5Xxh/XFq8xi5UnAYhRUkuIef3oZG4JMBlwxiBeiTxO/MOE1/G8YabNt4r ZONVa3cr5H777s8PZDNIPzQMWTk/R/nQV0zS9qtmpyMzWPr3y4fCji0uapFtOOPlbhfXe CjbH+mt6FGiGo76MB7xxwfAAlCkgHF/wsZQ39T06+FVKS6yLsplguuCuyyPq9IAPHxdk6 1YcLq7RpHAOyXeHiMaGr5qeWmzYDPqD7NtBDFP0uu9x35CGBRd1y7Ar3pfxmxwMa52sLm llKr18e+ET8qVkbiaguNh/NM+75ux1rAjGnjk6lYdxePT2DiGg7oo9Im7aWl7f5LJSg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=LD9sB6d6; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E3626606A9EE; Sat, 7 Nov 2026 15:14:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=LD9sB6d6 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 83AF21F008A3; Sat, 7 Nov 2026 15:14:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794064487; bh=28wqrs0w+f1Nw7Z8WPcti7aWS+wKg6ubG9fxeQsjbX0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LD9sB6d684Z8RuzgC+VEIEp+sJxxydCI4H1GXe22+bj/MdegjD+XwipcPXxLwrgmG X3SlrNqkElQ6IlPwIrSFcOomSYcgcF4b6Zugn6SCMRqRDWT4eXp0Kb9XLMSopmCcpv QyOilTrZhABZCvrEbW/SlHJV+Yc6ZBJTFwwj/Lek= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Thorsten Blum , Andrew Morton , Dan Moulding , Sasha Levin Subject: [PATCH 7.3 0524/1257] init: fix early boot crash with bare hostname parameter Date: Sat, 7 Nov 2026 08:47:00 -0500 Message-ID: <20261107134953.893763572@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thorsten Blum [ Upstream commit b6bec5b63a5b812145e53aaad1e63661c7214f93 ] When a bare hostname parameter is specified on the kernel command line without the '=' separator, early parameter parsing passes NULL to early_hostname(), which dereferences it in strscpy() and can crash the system during early boot. Reject NULL values in early_hostname() and return -EINVAL instead. Link: https://lore.kernel.org/20260826100904.296151-2-blum@kernel.org Fixes: 5a704629f2c1 ("init: add "hostname" kernel parameter") Signed-off-by: Thorsten Blum Signed-off-by: Andrew Morton Cc: Dan Moulding Cc: Signed-off-by: Sasha Levin --- init/version.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/init/version.c b/init/version.c index 94c96f6fbfe6a..0bd5c45aabc46 100644 --- a/init/version.c +++ b/init/version.c @@ -23,6 +23,9 @@ static int __init early_hostname(char *arg) size_t maxlen = bufsize - 1; ssize_t arglen; + if (!arg) + return -EINVAL; + arglen = strscpy(init_uts_ns.name.nodename, arg, bufsize); if (arglen < 0) { pr_warn("hostname parameter exceeds %zd characters and will be truncated", -- 2.53.0