From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9156780624; Fri, 2 Feb 2024 18:39:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706899184; cv=none; b=REWheEnoQ1hab6JrHSj95C7wAdnmHHdDhWtjAwNfI2ahp5M44iGiUQ9IGBLVRSii8rWkgcDhfQ5NpHs+Tb3MmVz9lLVSMgTWGtrzhliLsz3UNIsVbuNXgC1XTA54qPPZooHud3kNf95SkLaRg27Yb4l3QNemHRlPSCA+q1MmrhI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706899184; c=relaxed/simple; bh=J6bA4o8fW0UxqsXB3iPmtz3AJS29SvbfvIeBU08bDl0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XIBXvJrduslLk/3o4keCq7I4nrdrazf8KDej87nUNopHsGolYvjIODcBOokKtmPxC2MeuqaMknAzVrmqOKl0E96WC/IcuXA/zKXqyxjv/cGbYstwottXprE6pmqKMo+zmKKgFc+rWw4sp4bIWdNqbcMoU1FpMc10xGtk30hoTj0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=A2bMl2pJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="A2bMl2pJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E991AC433F1; Fri, 2 Feb 2024 18:39:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706899184; bh=J6bA4o8fW0UxqsXB3iPmtz3AJS29SvbfvIeBU08bDl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A2bMl2pJK9r63jCBUnsFZR9DQs68EMe40IeTQ0SClx2dLnuvXgrNmexk1jCa+a4ak MaYLJs4rYAUch5yxsEIzE7TY8zAIKihgFJzUiIiCsR9OHfIrP58s2fPtClwpEf40aU BHhzCWpMhHZbIpe7/vWESnSyZNIDmF13r6uzjvquFUuxH+KHBsNRLybNjBoJBHZob7 lMi+6EDAmEkUy1CpEUEHucDUL+E69oRR2dSi+ko04NUSdgTWIYzp3ZABQLeASXQ3V4 IJZcwFY7ATSDtvB4U7BdgNBuqeoqebKV1hf7Gu/xe7pq9m9p//XhOWbidUzZIZOAWU znoqe5HLee85w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kees Cook , Nathan Chancellor , Steve French , Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Tom Talpey , linux-cifs@vger.kernel.org, llvm@lists.linux.dev, Steve French , Sasha Levin , samba-technical@lists.samba.org Subject: [PATCH AUTOSEL 6.7 11/23] smb: Work around Clang __bdos() type confusion Date: Fri, 2 Feb 2024 13:39:07 -0500 Message-ID: <20240202183926.540467-11-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240202183926.540467-1-sashal@kernel.org> References: <20240202183926.540467-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.7.3 Content-Transfer-Encoding: 8bit From: Kees Cook [ Upstream commit 8deb05c84b63b4fdb8549e08942867a68924a5b8 ] Recent versions of Clang gets confused about the possible size of the "user" allocation, and CONFIG_FORTIFY_SOURCE ends up emitting a warning[1]: repro.c:126:4: warning: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] 126 | __write_overflow_field(p_size_field, size); | ^ for this memset(): int len; __le16 *user; ... len = ses->user_name ? strlen(ses->user_name) : 0; user = kmalloc(2 + (len * 2), GFP_KERNEL); ... if (len) { ... } else { memset(user, '\0', 2); } While Clang works on this bug[2], switch to using a direct assignment, which avoids memset() entirely which both simplifies the code and silences the false positive warning. (Making "len" size_t also silences the warning, but the direct assignment seems better.) Reported-by: Nathan Chancellor Closes: https://github.com/ClangBuiltLinux/linux/issues/1966 [1] Link: https://github.com/llvm/llvm-project/issues/77813 [2] Cc: Steve French Cc: Paulo Alcantara Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: linux-cifs@vger.kernel.org Cc: llvm@lists.linux.dev Signed-off-by: Kees Cook Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/smb/client/cifsencrypt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/smb/client/cifsencrypt.c b/fs/smb/client/cifsencrypt.c index ef4c2e3c9fa6..6322f0f68a17 100644 --- a/fs/smb/client/cifsencrypt.c +++ b/fs/smb/client/cifsencrypt.c @@ -572,7 +572,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash, len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp); UniStrupr(user); } else { - memset(user, '\0', 2); + *(u16 *)user = 0; } rc = crypto_shash_update(ses->server->secmech.hmacmd5, -- 2.43.0