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 13700132476; Fri, 2 Feb 2024 18:40:32 +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=1706899233; cv=none; b=Rnl92QbGZJ0yZHygigb+YHQKrmBVlY5rj4/jVIrjCqBqaCJC47jOZA+6Bbj8nmqdERpHkG9kWqBOoan/jtAyhIAQGr2IyNYeq7BgpLDv8S14T01xquXLBXgV1u+E0N1WUCCLz9l9fJ5DBrZZsd8Z67u9HvrQy4swWA4WzBwOJxw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706899233; c=relaxed/simple; bh=J6bA4o8fW0UxqsXB3iPmtz3AJS29SvbfvIeBU08bDl0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UezaAFeaiwFMzKLXDwvTKJdFFapiJNG/gZ3vYj26hXIGVSM538hNgIEdeeqbDzY/i2hhgX3TyquQYOWkkeEJJ+4Lu0E0iXmfuz0aAVAKmsNZtyRbOc4DqMoVNd6B8QkbsfSwfhO84Xagd11vUYhP/VLPDWrXonfaueJ4PGQjMek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=B78oDhuh; 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="B78oDhuh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 308F7C433F1; Fri, 2 Feb 2024 18:40:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706899232; bh=J6bA4o8fW0UxqsXB3iPmtz3AJS29SvbfvIeBU08bDl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B78oDhuhjS7Jr5FWICVGfwpHYvR49YLX5ozaaj4KFzQ4qOrJXTWXMNGdSA32O5NOE uVPuB3F8J9BrAtXKE1HOiJhOALiUg48tCnKRYo3KKVXum+keHN/fhWpBQKAYsJ8RpA e2BFbajLaeptjLigzDXlHAUjTPwP1Mx2i5rjO0zbKFBVQj0DrHCHLrNGHHHCDhZcc6 BU2JuO5HK6QHiTrXuF+wlCV1GGcSNVX70RA2PU9URKH/1ga/swJ/YVpGl6WN7/W4wS DqMTFFz9P7fn8yClV9Epu0QvFW2G/PCNjlIP+LMOq19xu0MrnTASMqywCNoaKn/y8g pqOpwhnA+ddWQ== 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 6.6 10/21] smb: Work around Clang __bdos() type confusion Date: Fri, 2 Feb 2024 13:39:57 -0500 Message-ID: <20240202184015.540966-10-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240202184015.540966-1-sashal@kernel.org> References: <20240202184015.540966-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.15 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