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=1793831708; b=S5KXO2E7isJLKsD1254ksFR1FT6FM4urzuXuAr1hjtTaD8zY3reE/ZIl7FqwqR/0Ft0f cvTiXUdDg8vMczb9hHnXUH553dAVabdgM+jIC6b75HRUhQPpQfOGnV313rVLTZEhcUFMC OH710//cIiDOknVyIWiKMwqjndE1JYVWdJrGmsKTAD9ERmsm4ST9VtjJfkKk2IhnuWShu vkZ/OMn8jRW2xqZzU2i8+YRNLf9J1PWUnD5AaAIAA5JSiw7bsRKhCN0pHjcXslnsWtp5+ DgftDtrfv6F24CpKBAD+7BHT+GBsL012e8SVx9ezeWuvy/jny2vmOCHNswkS9UOfhyQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793831708; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=EycqpjHVvKIBHEmZH2TWXQ+vYx/UGfaNE2v75f34Me8=; b=j/u15nxj65mTodrPlEniBXlVuw+0Khe+1TNW6HL1xmNMoalolCFfO/+KAGBHAiFheFh2 CqBXptfxsil5IsTl13Q6JmyJnzfutP4sxHfmZ/67OzGHcGlsvbb+mX3yjaEPTsNGrBXVp 5HEFqYJ/mIqFR4s51XQNVucZDsabA6H6v96cttQ3Jx8s6FLJUk39isyJGv5XQpxuyzAyU gTS9kDqrOXJBMqRJMkIcQvB+CG/RdT61uvrS6ARxImMH3ZECEiJfFA25kxpN0041Na9GS VtBqVOcWqviEdnK9/K1YwF7h4lDDZKGt3EWvPdSECVyFyrESRCZ9aMkNuGV6me/HGFw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=SkIHHCCk; 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 8286E606A337; Wed, 4 Nov 2026 22:35:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=SkIHHCCk Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1BE4B1F000C1; Wed, 4 Nov 2026 22:35:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793831708; bh=EycqpjHVvKIBHEmZH2TWXQ+vYx/UGfaNE2v75f34Me8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=SkIHHCCkrM42s+uc4jfmi63QR8UPtG59NGlcQ+G1iVcnjja9KHNSyYe6q0VmZiSJf ITPf07eIg4UruCKMf3FztuoBssoofZ3SlFmsid6BqDxBfA4B0xfMIU9GYbJ37lgW7j aSS3bMJnopBeDTxpAAZzxsFTVInu3BKH3SQDm3SA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, VeroFess , Namjae Jeon Subject: [PATCH 6.18 0866/1005] smb: server: size directory name conversion buffer correctly Date: Wed, 4 Nov 2026 16:09:59 -0500 Message-ID: <20261104211107.532279157@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: VeroFess commit f1f37834eaba5904103af1f18afe3510c7e9dc71 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- fs/smb/server/misc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/fs/smb/server/misc.c +++ b/fs/smb/server/misc.c @@ -291,12 +291,13 @@ char *ksmbd_convert_dir_info_name(struct 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, KSMBD_DEFAULT_GFP); + /* One UTF-16 code unit per input byte, plus the terminating NUL. */ + conv = kmalloc_array((size_t)d_info->name_len + 1, + sizeof(__le16), KSMBD_DEFAULT_GFP); if (!conv) return NULL; @@ -305,7 +306,6 @@ char *ksmbd_convert_dir_info_name(struct 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;