From patchwork Wed Sep 25 09:03:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thorsten Blum X-Patchwork-Id: 13811813 Received: from out-186.mta0.migadu.com (out-186.mta0.migadu.com [91.218.175.186]) (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 97C2215990C for ; Wed, 25 Sep 2024 09:10:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.186 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727255458; cv=none; b=qya0A6aKlFnYslHF5aQWq6SDC0jL2XBBU68xKWi/zVv76XrrHDYVuAuzc7MS2WBEXZe55XN9MPJr42Vi2uQu6UXO22TRQTNDpFQhoQBSk+9Z65/r6Om7T6DqBq95GJHTxeEv7yDRk77CRjhpwY45Su1KGqD/nmtpoAOkrB4yvWg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727255458; c=relaxed/simple; bh=qPOG89odr6nDTu/Y0IRoN41sQE1eJDpORZJc6ao2/mM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=EH/QlxgsiaL0d5TjsEdvVJpef9ZLYhoDxpKQkyOpQqA/u5GVhU0XD7ohHjbxB5e/E08GKyn0+Ticl2EZFocnsr6KFzDcTjdCoJNhhkAouDmbo8BvUJTSDP0i5F52c2WASFwo5OyWHIfmQmdAccxGZD9d1IhPiKaLDeK1w9R3ocM= 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=cLAfyS83; arc=none smtp.client-ip=91.218.175.186 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="cLAfyS83" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1727255453; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=oNcOfjKU7tZbJlgaRWEUdhjUY7VzCvgYazdTewJBeUM=; b=cLAfyS83tgbMVyk6ddVbF2rKh47lmtTJCfz+5gcDdwzjDoHimv3u2jj2SireheVvE7JTHp YcRsPu3P1ZhH9xJWe3kS2Jl7ek9FZEWgVxV+yjmvC8s7Ut9cH0dmhJEu71Bj+MafntYTrR GdzoJTeSCgKbmjKsDDeNcXK9AzmHoHY= From: Thorsten Blum To: Namjae Jeon , Steve French , Sergey Senozhatsky , Tom Talpey , Kees Cook , "Gustavo A. R. Silva" Cc: Thorsten Blum , linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2] ksmbd: Annotate struct copychunk_ioctl_req with __counted_by_le() Date: Wed, 25 Sep 2024 11:03:13 +0200 Message-ID: <20240925090313.22310-2-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Add the __counted_by_le compiler attribute to the flexible array member Chunks to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE. Change the data type of the flexible array member Chunks from __u8[] to struct srv_copychunk[] for ChunkCount to match the number of elements in the Chunks array. (With __u8[], each srv_copychunk would occupy 24 array entries and the __counted_by compiler attribute wouldn't be applicable.) Use struct_size() to calculate the size of the copychunk_ioctl_req. Read Chunks[0] after checking that ChunkCount is not 0. Compile-tested only. Signed-off-by: Thorsten Blum --- Changes in v2: - Change the data type of Chunks from __u8[] to struct srv_copychunk[] as suggested by Tom Talpey - Use struct_size() - Link to v1: https://lore.kernel.org/linux-kernel/20240924102243.239811-2-thorsten.blum@linux.dev/ --- fs/smb/server/smb2pdu.c | 5 ++--- fs/smb/server/smb2pdu.h | 14 +++++++------- 2 files changed, 9 insertions(+), 10 deletions(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 7121266daa02..62312c5e790e 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -7566,7 +7566,6 @@ static int fsctl_copychunk(struct ksmbd_work *work, ci_rsp->TotalBytesWritten = cpu_to_le32(ksmbd_server_side_copy_max_total_size()); - chunks = (struct srv_copychunk *)&ci_req->Chunks[0]; chunk_count = le32_to_cpu(ci_req->ChunkCount); if (chunk_count == 0) goto out; @@ -7574,12 +7573,12 @@ static int fsctl_copychunk(struct ksmbd_work *work, /* verify the SRV_COPYCHUNK_COPY packet */ if (chunk_count > ksmbd_server_side_copy_max_chunk_count() || - input_count < offsetof(struct copychunk_ioctl_req, Chunks) + - chunk_count * sizeof(struct srv_copychunk)) { + input_count < struct_size(ci_req, Chunks, chunk_count)) { rsp->hdr.Status = STATUS_INVALID_PARAMETER; return -EINVAL; } + chunks = &ci_req->Chunks[0]; for (i = 0; i < chunk_count; i++) { if (le32_to_cpu(chunks[i].Length) == 0 || le32_to_cpu(chunks[i].Length) > ksmbd_server_side_copy_max_chunk_size()) diff --git a/fs/smb/server/smb2pdu.h b/fs/smb/server/smb2pdu.h index 73aff20e22d0..649dacf7e8c4 100644 --- a/fs/smb/server/smb2pdu.h +++ b/fs/smb/server/smb2pdu.h @@ -190,13 +190,6 @@ struct resume_key_ioctl_rsp { __u8 Context[4]; /* ignored, Windows sets to 4 bytes of zero */ } __packed; -struct copychunk_ioctl_req { - __le64 ResumeKey[3]; - __le32 ChunkCount; - __le32 Reserved; - __u8 Chunks[]; /* array of srv_copychunk */ -} __packed; - struct srv_copychunk { __le64 SourceOffset; __le64 TargetOffset; @@ -204,6 +197,13 @@ struct srv_copychunk { __le32 Reserved; } __packed; +struct copychunk_ioctl_req { + __le64 ResumeKey[3]; + __le32 ChunkCount; + __le32 Reserved; + struct srv_copychunk Chunks[] __counted_by_le(ChunkCount); +} __packed; + struct copychunk_ioctl_rsp { __le32 ChunksWritten; __le32 ChunkBytesWritten;