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=1793898830; b=WjH0O3rrYhxyVPu8XlrrIdzyntP//ZZbOdyPyMrCS1IgLOepUvNkFdNiyGsQ5DdFKEK8 K+q/dE77wHk1lRU4+mhKvwxw8tRrioy6KclBzdNB4JBudb3i4C3tZHpBQx5WhhlatMd7y cEAXyr4m+feq23Kwt8TgquFh0JLaUwu1xX389TxfxszbZW8bAmujhuK5sf6Si7BTr9b15 zkSgslLgxoGa2kZWmPVKAbqH7w3CTmFGzpWaUZymVtyFplVCrFwN/AwrIziw6P66Pavsl LZqdWbbL6pIG7RcsjzYuCwJOOFdL30oSknGge5khUBec+09R5LEOZrAzNBK1QcznBEQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793898830; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=e9lbHjL1/Sm4sdjLBSc6zBB9t6Ek9LZiuMFNDdw3z94=; b=IizghSPLbR3F+A+r1ACz5cUz5S/5jMCtHrTR+crg0n1HyoJc2P/WLdU3vuLgTC9LakA/ YfJG1HPPoQqgEhBlFHq648si83Gmrc71snGW9yQvCKt18djny5l0ktruS+6fXwGksscWY AoPu1rBm2ugzxhO6qmwqOJFWdlYlmpWbY2qKHce3iLwqTEBPv+tgIZYRuEYrHbYWR7HgK 9Zk+J6taFqlbWo/3mkIwx2mEfw9XLlsi7ynDNb4OSwWgGME/+mYmLA2Vr3WzszXg74Ems dw+pEMZz23YwZNppntH//azN+XGJSjRJ+2nDG3GTJv5hgCAa66vYMkUJECRgYv62GyQ== 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=CJZD6iPE; 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 F1699606D822 for ; Thu, 5 Nov 2026 17:13:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=CJZD6iPE Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20D8D1F000C1; Thu, 5 Nov 2026 17:13:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793898829; bh=e9lbHjL1/Sm4sdjLBSc6zBB9t6Ek9LZiuMFNDdw3z94=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CJZD6iPEWVQhhufMFCs2qSw3Dl33p+B5JNCciY0Qxn/RlEQuXDq5T7hNCmod3aLGC 6i4DztO/R2HnNEjx82MKNxA8Ck012O9xVCuGwmZYcAcBHh5GYgfOrq2xJizk54NPeS sVIocPW8LLnJerBxnLjyA8nm2B+/d30MDyss2/HcTt8P/zy07mQbQsCUquHTWncaM0 pBHa8b0/hWIXO98jmpX47npFJ5qg+kVJjo3QfGTKEhD0O9objoC9xn6GI6fN1utqhU 6YOJ2+AB0XFfYQDtfcUuqs18uJSg39JqXaS8fiezonAUoOEC6XCyN6FHVbDhMSqBz+ RY0nqYggS3FwA== From: Sasha Levin To: stable@vger.kernel.org Cc: VeroFess , Namjae Jeon , Sasha Levin Subject: [PATCH 6.6.y] smb: server: size directory name conversion buffer correctly Date: Thu, 5 Nov 2026 12:13:47 -0500 Message-ID: <20261105171319.2151172-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026110424-submarine-stool-e2c1@gregkh> References: <2026110424-submarine-stool-e2c1@gregkh> 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: VeroFess [ Upstream commit f1f37834eaba5904103af1f18afe3510c7e9dc71 ] A 2048-byte ASCII directory name needs 4098 bytes when converted to UTF-16, including the terminator. ksmbd_convert_dir_info_name() caps its allocation at PATH_MAX and writes past the end of that buffer. Allocate space for one UTF-16 code unit per input byte plus the terminator. Use kmalloc_array() to check the size calculation. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Cc: stable@vger.kernel.org Assisted-by: gpt 6 sol with daybreak blue Signed-off-by: VeroFess Signed-off-by: Namjae Jeon [ sashal: Retained GFP_KERNEL instead of KSMBD_DEFAULT_GFP because the latter is unavailable. ] Signed-off-by: Sasha Levin --- fs/smb/server/misc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/smb/server/misc.c b/fs/smb/server/misc.c index 79de46a0283ab..604d8584fb2bd 100644 --- a/fs/smb/server/misc.c +++ b/fs/smb/server/misc.c @@ -290,12 +290,13 @@ char *ksmbd_convert_dir_info_name(struct ksmbd_dir_info *d_info, int *conv_len) { char *conv; - int sz = min(4 * d_info->name_len, PATH_MAX); - if (!sz) + if (d_info->name_len <= 0) return NULL; - conv = kmalloc(sz, GFP_KERNEL); + /* One UTF-16 code unit per input byte, plus the terminating NUL. */ + conv = kmalloc_array((size_t)d_info->name_len + 1, + sizeof(__le16), GFP_KERNEL); if (!conv) return NULL; @@ -304,7 +305,6 @@ char *ksmbd_convert_dir_info_name(struct ksmbd_dir_info *d_info, d_info->name_len, local_nls, 0); *conv_len *= 2; - /* We allocate buffer twice bigger than needed. */ conv[*conv_len] = 0x00; conv[*conv_len + 1] = 0x00; return conv; -- 2.53.0