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=1794321630; b=vjCOiX2n7WcvLMZzU1ZubksUc3NVn1rbB/dHVJLLxSQNX4WCR1vnDLIVxprVvu9ptwE2 Gw37cFtZMejZWXJ6WP8vQuo15UXKa6eFxxYERuveVoGP1u22MPNwqJO33k3ZKTKEiOJdn zGtFMOYJ1Ynl1ab2RmafzxAljkSgPcUXkGswI7T6UlZDl8he6lJuJc0B9JMgo61ZNW0j+ ZcAfsRfP5XruaIVFILBe6j0jlsGkxzMAVGd4TjxFf40KWFxHRQzvxZyfLVNXp9ufPolUu VxqsB/8pd4ynYqix3lv7XuS35vg8D350Qa2W6B6bMnCz5ocItGtL/LvbHJVugGG39rw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794321630; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=iDnhWwNWIWHFRc+GA0lD6SNMhHWBVbPXAdnd9zGF9FM=; b=AkG02cgv4bsfaPjnAB8TXbj/Qh/HEWVLB/EE7QH/dQHxdTgXIdukVees+t3myaJxdMpe zbFN44PVBcHOuM0i7KDp5uBwe6lysvCayZLHyGrf9ofsF3xeNrCeBtDyars0YN67LbFN7 So7MypCLjJyo8gRmHRUCZo2OUevDlplXJYLoo0EQmU7V5HCcBLGJURZMKu9CQ4X6B+kh0 faBLn1GeBqtqvNRBBlIFd5rLcRCiAjIkzAlU9ie5+HaivCkshNWs1+m6dav3svPiA/Es0 6a0iKO4MqnggKc0xmKwPet3nlBv2+EqicZU7D/XKvaWGVnnffzZCXxjMu249pCqqm2Q== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=aik4i2YF; 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 9FE4760A261C for ; Tue, 10 Nov 2026 14:40:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=aik4i2YF Received: by smtp.kernel.org (Postfix) with ESMTPSA id D62C11F0089F; Tue, 10 Nov 2026 14:40:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794321630; bh=iDnhWwNWIWHFRc+GA0lD6SNMhHWBVbPXAdnd9zGF9FM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=aik4i2YFGOP7H7z4AcoaK6OabEabK7YV14YDaFXJLmd3SzUdIED2VE6/Bt9RJWjJs 9ER/XkUWgJJZkhae5fOtLvn0FlL085FBg3YixukJLrRSSxKOsWQZYjdPJiQSyhguC+ jXONpILIRlPiaP8C0+4kw8j8dLAeKt2N7pYnH2vMZjaGDyDUOYBBk76Wrcs+n+C11N XdJjHNSuQ7FhGUvT0+uP3o67d2fF6hYZfrd7ha9NzOTVZV+Yn4J7KDc7tGLK6cbWtq sGZN630k808yZ8ZWNNFvsDNZ1RF3zNvW1Rh6wlEYMdyCAVHGIZj7zzmkksxlvmnfsr MSCxQVj076NtQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Thorsten Blum , Andrew Morton , Dan Moulding , Sasha Levin Subject: [PATCH 6.1.y 2/2] init: fix early boot crash with bare hostname parameter Date: Tue, 10 Nov 2026 09:40:27 -0500 Message-ID: <20261110144018.1943926-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261110144018.1943926-1-sashal@kernel.org> References: <20261107054505-failed-6.1-b6bec5b63a5b@kernel.org> <20261110144018.1943926-1-sashal@kernel.org> 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 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 221ccede8902a..11cbd3fb60be5 100644 --- a/init/version.c +++ b/init/version.c @@ -24,6 +24,9 @@ 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