From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-157.mta0.migadu.com [91.218.175.157]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C9BB377AA7 for ; Thu, 13 Aug 2026 08:22:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.157 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786609341; cv=none; b=oeO9sRoU08cKtvKaU9IfBeCCYRfGD3UDWc8HiWTwoqxQGrxZvXenMMj7RcPaeZvnSjU3rr9L054sb+KwqVvMWdX8exiyLo8aDJ/ZXSbwvKhZq2pmmowcAjVyBgEhN0YMx7CPgSsiVMUqZzoKnTNDjOjeNRLQt2Ztsx3Q33gCD08= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786609341; c=relaxed/simple; bh=pxk76wC4TAnTsZKwj0UIutLV3kMVPp7RrfYY/k2CTxs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=NONQ+iEAhn1MuO7Wl+WosDUz/GgOZx005dFA31lL9Hyf8XD8TBJM5as4iWyBVRqYHeoVi2memC51BJMwCSNa11h0EUdo/g39gdAzhEOSV584arJf9VcC1ko+Uw27CZg5mqB9SchNzhjayLcEA+ooBwcYY60FOGaiFWeaBsLN4eU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=vv4VMlN+; arc=none smtp.client-ip=91.218.175.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="vv4VMlN+" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=pxk76wC4TAnTsZKwj0UIutLV3kMVPp7RrfYY/k2CTxs=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1786609337; v=1; x=1787214137; b=vv4VMlN+Aq0NKxpFuQb0ir6XJ+6PNIVxDZzPs+SAGD635pqIsJp+6rvsO0f+W5v7x1+6JpXE pGK9mi/w4e0McgrsOou83CTfh8GQCxDMeWMqEQXk9GvNhq62X6e1xUZhXrmHdbQxW+LaegsCGBT IN3eh3PZR3RI4aFneNM9XLOM= X-Envelope-To: linux-kernel@vger.kernel.org Received: from fedora.fritz.box (62.216.208.217) by mta10.migadu.com with ESMTPS id 29a3cc04b4b5c0e5; Thu, 13 Aug 2026 08:22:17 +0000 X-Migadu-Flow: FLOW_OUT From: Thorsten Blum To: Mark Pearson , "Derek J. Clark" , Hans de Goede , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Cc: Thorsten Blum , stable@vger.kernel.org, Mark Pearson , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] platform/x86: think-lmi: Fix current password length check Date: Thu, 13 Aug 2026 10:20:49 +0200 Message-ID: <20260813082049.41209-2-thorsten.blum@linux.dev> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1797; i=thorsten.blum@linux.dev; h=from:subject; bh=pxk76wC4TAnTsZKwj0UIutLV3kMVPp7RrfYY/k2CTxs=; b=owGbwMvMwCUWt7pQ4caZUj3G02pJDFm1dYmXFaU2NM1tu81odurZ1+zq19UCbr6eNsX+HB+dO N1mtRp0lLIwiHExyIopsjyY9WOGb2lN5SaTiJ0wc1iZQIYwcHEKwETc1jL8FeG6cXxdudWBPWyL TtQrLXhftOlLdoaXZqzGsxreJzPMdjP84a10nGGp9+9h25yOS1tmuP4wf2PC/76EqeCl+B1p94N F7AA= X-Developer-Key: i=thorsten.blum@linux.dev; a=openpgp; fpr=1D60735E8AEF3BE473B69D84733678FD8DFEEAD4 Content-Transfer-Encoding: 8bit current_password_store() checks the password length before removing the trailing newline, which can reject valid passwords that are exactly ->maxlen bytes long. It also passes ->maxlen to strscpy(), which truncates passwords without a newline. Use strchrnul() to measure the password length up to the newline, then copy that many bytes and add a trailing NUL terminator. Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms") Cc: stable@vger.kernel.org Signed-off-by: Thorsten Blum --- Changes in v2: - Keep and reword the newline comment - v1: https://lore.kernel.org/r/20260810132018.156868-3-thorsten.blum@linux.dev/ --- drivers/platform/x86/lenovo/think-lmi.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/platform/x86/lenovo/think-lmi.c b/drivers/platform/x86/lenovo/think-lmi.c index e215e86e3db7..d0ceb6aaa69e 100644 --- a/drivers/platform/x86/lenovo/think-lmi.c +++ b/drivers/platform/x86/lenovo/think-lmi.c @@ -438,14 +438,14 @@ static ssize_t current_password_store(struct kobject *kobj, struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); size_t pwdlen; - pwdlen = strlen(buf); + /* Strip newline; setting password won't work if one is present. */ + pwdlen = strchrnul(buf, '\n') - buf; /* pwdlen == 0 is allowed to clear the password */ if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) return -EINVAL; - strscpy(setting->password, buf, setting->maxlen); - /* Strip out CR if one is present, setting password won't work if it is present */ - strreplace(setting->password, '\n', '\0'); + memcpy(setting->password, buf, pwdlen); + setting->password[pwdlen] = '\0'; return count; }