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[147.75.48.161]) by mx.google.com with ESMTPS id m185-20020a6326c2000000b005cdf878b0f5si1572820pgm.856.2024.01.26.11.34.38 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Jan 2024 11:34:38 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-40573-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161; Authentication-Results: mx.google.com; arc=pass (i=1 spf=pass spfdomain=altlinux.org); spf=pass (google.com: domain of linux-kernel+bounces-40573-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) smtp.mailfrom="linux-kernel+bounces-40573-ouuuleilei=gmail.com@vger.kernel.org" Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sy.mirrors.kernel.org (Postfix) with ESMTPS id CE55EB24F1D for ; Fri, 26 Jan 2024 19:33:31 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 9FF4A24A11; Fri, 26 Jan 2024 19:32:17 +0000 (UTC) Received: from air.basealt.ru (air.basealt.ru [194.107.17.39]) (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 638932375C; Fri, 26 Jan 2024 19:32:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.107.17.39 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706297535; cv=none; b=bj7Zt1ogeAX4LG+vGwhVOovqOYG7v2tAqBDmpGqE7z0GF9fVNqriEAp7h6ecOfZ9HsP1TLBwgVTj9FHI21TSrI50e1RpkjArOhB+WNkxEdz/6kFZjx9X2kpUQRYzApWuV5F1OgxCNB/An1K0kYfKc26gw7kVQ+v6QIsgtdlEnbQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706297535; c=relaxed/simple; bh=kBUsdBRGibggPisS6UgH+qECKvgWl3qwx3c5ZrsthAo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Z7cjrlUYqn6WoU7/ayv/hko/KCo7O2KgbwfFkVgBuUlz823keMJKzLsRSG26/AUuXbIlkjUe9tafAVnxG7D86vr/VAHXYcuO5E/btwZndGIacC2+BYNnz6r2VnRKHSK+j/n9SH7UAX1Bc40pER3brIOyZvHf15/wpwH2tF5Ksts= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=altlinux.org; spf=pass smtp.mailfrom=altlinux.org; arc=none smtp.client-ip=194.107.17.39 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=altlinux.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=altlinux.org Received: by air.basealt.ru (Postfix, from userid 490) id 3A0182F2023E; Fri, 26 Jan 2024 19:32:10 +0000 (UTC) X-Spam-Level: Received: from altlinux.ipa.basealt.ru (unknown [178.76.204.78]) by air.basealt.ru (Postfix) with ESMTPSA id 5C7532F20238; Fri, 26 Jan 2024 19:32:05 +0000 (UTC) From: kovalev@altlinux.org To: stable@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org Cc: keescook@chromium.org, sfrench@samba.org, corbet@lwn.net, natechancellor@gmail.com, ndesaulniers@google.com, kovalev@altlinux.org, Arnd Bergmann , "Gustavo A. R. Silva" Subject: [PATCH 1/2] stddef: Introduce DECLARE_FLEX_ARRAY() helper Date: Fri, 26 Jan 2024 22:31:42 +0300 Message-Id: <20240126193143.245122-2-kovalev@altlinux.org> X-Mailer: git-send-email 2.33.8 In-Reply-To: <20240126193143.245122-1-kovalev@altlinux.org> References: <20240126193143.245122-1-kovalev@altlinux.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1789182794830130184 X-GMAIL-MSGID: 1789182794830130184 From: Kees Cook commit 3080ea5553cc909b000d1f1d964a9041962f2c5b upstream. There are many places where kernel code wants to have several different typed trailing flexible arrays. This would normally be done with multiple flexible arrays in a union, but since GCC and Clang don't (on the surface) allow this, there have been many open-coded workarounds, usually involving neighboring 0-element arrays at the end of a structure. For example, instead of something like this: struct thing { ... union { struct type1 foo[]; struct type2 bar[]; }; }; code works around the compiler with: struct thing { ... struct type1 foo[0]; struct type2 bar[]; }; Another case is when a flexible array is wanted as the single member within a struct (which itself is usually in a union). For example, this would be worked around as: union many { ... struct { struct type3 baz[0]; }; }; These kinds of work-arounds cause problems with size checks against such zero-element arrays (for example when building with -Warray-bounds and -Wzero-length-bounds, and with the coming FORTIFY_SOURCE improvements), so they must all be converted to "real" flexible arrays, avoiding warnings like this: fs/hpfs/anode.c: In function 'hpfs_add_sector_to_btree': fs/hpfs/anode.c:209:27: warning: array subscript 0 is outside the bounds of an interior zero-length array 'struct bplus_internal_node[0]' [-Wzero-length-bounds] 209 | anode->btree.u.internal[0].down = cpu_to_le32(a); | ~~~~~~~~~~~~~~~~~~~~~~~^~~ In file included from fs/hpfs/hpfs_fn.h:26, from fs/hpfs/anode.c:10: fs/hpfs/hpfs.h:412:32: note: while referencing 'internal' 412 | struct bplus_internal_node internal[0]; /* (internal) 2-word entries giving | ^~~~~~~~ drivers/net/can/usb/etas_es58x/es58x_fd.c: In function 'es58x_fd_tx_can_msg': drivers/net/can/usb/etas_es58x/es58x_fd.c:360:35: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[]'} [-Wzero-length-bounds] 360 | tx_can_msg = (typeof(tx_can_msg))&es58x_fd_urb_cmd->raw_msg[msg_len]; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from drivers/net/can/usb/etas_es58x/es58x_core.h:22, from drivers/net/can/usb/etas_es58x/es58x_fd.c:17: drivers/net/can/usb/etas_es58x/es58x_fd.h:231:6: note: while referencing 'raw_msg' 231 | u8 raw_msg[0]; | ^~~~~~~ However, it _is_ entirely possible to have one or more flexible arrays in a struct or union: it just has to be in another struct. And since it cannot be alone in a struct, such a struct must have at least 1 other named member -- but that member can be zero sized. Wrap all this nonsense into the new DECLARE_FLEX_ARRAY() in support of having flexible arrays in unions (or alone in a struct). As with struct_group(), since this is needed in UAPI headers as well, implement the core there, with a non-UAPI wrapper. Additionally update kernel-doc to understand its existence. https://github.com/KSPP/linux/issues/137 Cc: Arnd Bergmann Cc: "Gustavo A. R. Silva" Signed-off-by: Kees Cook Signed-off-by: Vasiliy Kovalev --- include/linux/stddef.h | 13 +++++++++++++ include/uapi/linux/stddef.h | 16 ++++++++++++++++ scripts/kernel-doc | 3 ++- 3 files changed, 31 insertions(+), 1 deletion(-) diff --git a/include/linux/stddef.h b/include/linux/stddef.h index 938216f8ab7e7c..31fdbb784c24e2 100644 --- a/include/linux/stddef.h +++ b/include/linux/stddef.h @@ -84,4 +84,17 @@ enum { #define struct_group_tagged(TAG, NAME, MEMBERS...) \ __struct_group(TAG, NAME, /* no attrs */, MEMBERS) +/** + * DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union + * + * @TYPE: The type of each flexible array element + * @NAME: The name of the flexible array member + * + * In order to have a flexible array member in a union or alone in a + * struct, it needs to be wrapped in an anonymous struct with at least 1 + * named member, but that member can be empty. + */ +#define DECLARE_FLEX_ARRAY(TYPE, NAME) \ + __DECLARE_FLEX_ARRAY(TYPE, NAME) + #endif diff --git a/include/uapi/linux/stddef.h b/include/uapi/linux/stddef.h index c3725b49226323..7837ba4fe72890 100644 --- a/include/uapi/linux/stddef.h +++ b/include/uapi/linux/stddef.h @@ -28,4 +28,20 @@ struct { MEMBERS } ATTRS; \ struct TAG { MEMBERS } ATTRS NAME; \ } + +/** + * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union + * + * @TYPE: The type of each flexible array element + * @NAME: The name of the flexible array member + * + * In order to have a flexible array member in a union or alone in a + * struct, it needs to be wrapped in an anonymous struct with at least 1 + * named member, but that member can be empty. + */ +#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ + struct { \ + struct { } __empty_ ## NAME; \ + TYPE NAME[]; \ + } #endif diff --git a/scripts/kernel-doc b/scripts/kernel-doc index 19af6dd160e6b7..7a04d4c0532607 100755 --- a/scripts/kernel-doc +++ b/scripts/kernel-doc @@ -1232,7 +1232,8 @@ sub dump_struct($$) { $members =~ s/DECLARE_KFIFO\s*\(([^,)]+),\s*([^,)]+),\s*([^,)]+)\)/$2 \*$1/gos; # replace DECLARE_KFIFO_PTR $members =~ s/DECLARE_KFIFO_PTR\s*\(([^,)]+),\s*([^,)]+)\)/$2 \*$1/gos; - + # replace DECLARE_FLEX_ARRAY + $members =~ s/(?:__)?DECLARE_FLEX_ARRAY\s*\($args,\s*$args\)/$1 $2\[\]/gos; my $declaration = $members; # Split nested struct/union elements as newer ones From patchwork Fri Jan 26 19:31:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasiliy Kovalev X-Patchwork-Id: 192768 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:7301:2395:b0:106:343:edcb with SMTP id gw21csp104352dyb; Fri, 26 Jan 2024 11:34:08 -0800 (PST) X-Google-Smtp-Source: AGHT+IFu06+J1ASQ7Q53OGFfb3Y4pbV330RDIBpofXG2Oxhq0DKxeEN4MDZ/GSuHFY+1f4LGIuWq X-Received: by 2002:a17:90a:9b07:b0:293:f430:2c25 with SMTP id f7-20020a17090a9b0700b00293f4302c25mr333963pjp.5.1706297648657; Fri, 26 Jan 2024 11:34:08 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1706297648; cv=pass; d=google.com; s=arc-20160816; b=bLtNXfHeXNwb1vT4H0fOfGIC9Dbaev4Q8PFN4wv3qaXH8RPrTk7ouEcGPvOr4K5r+X oa42oyQCPUqlhxxtNqy32L22NxWxI42f1ussOcpTZ7b61V+nUWb+ZcXEiLE+iwsvAsT0 POuYEOA9o8bb6yDEjsLqy9Oa3OHFPHSft5pZIAAQKI6fSCwM7BqaWFd1SEXrSUPyg7zY 7e6U75UVvxV0IsCGMnw0OuF8cpQlfVe/EHhSsBncNmbWfW8LEORl1kFt+Xcf7VU+N6Yr umXjSM01YV6NPePsnlIq60jNgpLU2zrBFgaHk359AwsjEs+DyS6urXQVgerfQEWAfquG J/wg== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:list-unsubscribe :list-subscribe:list-id:precedence:references:in-reply-to:message-id :date:subject:cc:to:from; bh=h1p58mxLrxCR+ElXXRtul4MYui91IiabsC2ss3x7r4c=; fh=qYHSTmKnrhPlH+yuXveiuhpz2oCK1oAtcAiSPh6mYXc=; b=BtXOAeQPgkBVyw0tbhaZ8fmcDmC/1xw5hOQh/yWleKNwAcOOhcgle/OsmNMg+Su1Ek Bkt+zthBFGhv1aVsmj04gldhELyeEeOBqrJmgA8Vfiy5T1MmCCYq8qloMR4IVag65BNF OkUM8B2xthxw2+T2adO+SXyyfsNLEuCQRunmRtqeFYLcVuQQ6Bx2YEV/4s/jR3d6iIlb 7zQstJZZVYdkxitFLMlcKrOCNdE5J2HMsyxgWZBNbwuYmM7T0Bv5k/imekotaJ3ClJ0X LOWz7/rOGg4B+rbsfaMTjfE8LL3hMdlaC8LV8RxUyQQ9kv/l7eV7iKlqYeKUk9awZdRr 0KnA== ARC-Authentication-Results: i=2; mx.google.com; arc=pass (i=1 spf=pass spfdomain=altlinux.org); spf=pass (google.com: domain of linux-kernel+bounces-40574-ouuuleilei=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-40574-ouuuleilei=gmail.com@vger.kernel.org" Received: from sv.mirrors.kernel.org (sv.mirrors.kernel.org. [2604:1380:45e3:2400::1]) by mx.google.com with ESMTPS id 3-20020a17090a098300b0028e114463b1si1594086pjo.60.2024.01.26.11.34.08 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Jan 2024 11:34:08 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-40574-ouuuleilei=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1; Authentication-Results: mx.google.com; arc=pass (i=1 spf=pass spfdomain=altlinux.org); spf=pass (google.com: domain of linux-kernel+bounces-40574-ouuuleilei=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-40574-ouuuleilei=gmail.com@vger.kernel.org" Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id C030A284ECF for ; Fri, 26 Jan 2024 19:33:44 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6AB8D250EA; Fri, 26 Jan 2024 19:32:20 +0000 (UTC) Received: from air.basealt.ru (air.basealt.ru [194.107.17.39]) (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 5123D23758; Fri, 26 Jan 2024 19:32:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.107.17.39 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706297537; cv=none; b=HCeiLQz7ERpD0sIOnPBu0ZWibCdFAn9UyfdjJmqwitHNk2cacpZ4yH/3DIO7GsImdlH2yseCKCYkBC5cLBcqbS2at/pXLcvnOPhxW0S5fWn/TBlj4Nfx/YGXf6nCVjwft3/06KbgHgWF4dzEdd4kEHfXyF8Y2RsSMah/Na8r47M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706297537; c=relaxed/simple; bh=mLtfa9rwa4Wd1aOztK+WeQOfWlOnVbtGjfUfZIKPPZ8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=MHPJFMNK0ueA9m5GWjTZKErkrDZ48+5l/wnj2Wln8+VQ++/nhbjY4euMVGTx0lrALAvNSVD4dTe3hNU5we5nZbuCsa7HyZYSVClZb4QcQ3jwbjTRR3hs4zxYnSwiuTo7ZJRr0qaVQYNTkVoO2Sig5/2JYTygjhESyAxCgHQ4/Mw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=altlinux.org; spf=pass smtp.mailfrom=altlinux.org; arc=none smtp.client-ip=194.107.17.39 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=altlinux.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=altlinux.org Received: by air.basealt.ru (Postfix, from userid 490) id 157FB2F20236; Fri, 26 Jan 2024 19:32:12 +0000 (UTC) X-Spam-Level: Received: from altlinux.ipa.basealt.ru (unknown [178.76.204.78]) by air.basealt.ru (Postfix) with ESMTPSA id 3EFD22F2023B; Fri, 26 Jan 2024 19:32:06 +0000 (UTC) From: kovalev@altlinux.org To: stable@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org Cc: keescook@chromium.org, sfrench@samba.org, corbet@lwn.net, natechancellor@gmail.com, ndesaulniers@google.com, kovalev@altlinux.org, Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Tom Talpey , Namjae Jeon , Sergey Senozhatsky , Steve French Subject: [PATCH 2/2] smb3: Replace smb2pdu 1-element arrays with flex-arrays Date: Fri, 26 Jan 2024 22:31:43 +0300 Message-Id: <20240126193143.245122-3-kovalev@altlinux.org> X-Mailer: git-send-email 2.33.8 In-Reply-To: <20240126193143.245122-1-kovalev@altlinux.org> References: <20240126193143.245122-1-kovalev@altlinux.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1789182763385463207 X-GMAIL-MSGID: 1789182763385463207 From: Kees Cook commit eb3e28c1e89b4984308777231887e41aa8a0151f upstream. The kernel is globally removing the ambiguous 0-length and 1-element arrays in favor of flexible arrays, so that we can gain both compile-time and run-time array bounds checking[1]. Replace the trailing 1-element array with a flexible array in the following structures: struct smb2_err_rsp struct smb2_tree_connect_req struct smb2_negotiate_rsp struct smb2_sess_setup_req struct smb2_sess_setup_rsp struct smb2_read_req struct smb2_read_rsp struct smb2_write_req struct smb2_write_rsp struct smb2_query_directory_req struct smb2_query_directory_rsp struct smb2_set_info_req struct smb2_change_notify_rsp struct smb2_create_rsp struct smb2_query_info_req struct smb2_query_info_rsp Replace the trailing 1-element array with a flexible array, but leave the existing structure padding: struct smb2_file_all_info struct smb2_lock_req Adjust all related size calculations to match the changes to sizeof(). No machine code output or .data section differences are produced after these changes. [1] For lots of details, see both: https://docs.kernel.org/process/deprecated.html#zero-length-and-one-element-arrays https://people.kernel.org/kees/bounded-flexible-arrays-in-c Cc: Steve French Cc: Paulo Alcantara Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Namjae Jeon Cc: Sergey Senozhatsky Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Reviewed-by: Namjae Jeon Signed-off-by: Kees Cook Signed-off-by: Steve French Signed-off-by: Vasiliy Kovalev --- fs/cifs/smb2misc.c | 2 +- fs/cifs/smb2ops.c | 14 +++++++------- fs/cifs/smb2pdu.c | 13 ++++++------- fs/cifs/smb2pdu.h | 42 ++++++++++++++++++++++++------------------ 4 files changed, 38 insertions(+), 33 deletions(-) diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c index b98bba887f84b0..660e00eb42060a 100644 --- a/fs/cifs/smb2misc.c +++ b/fs/cifs/smb2misc.c @@ -117,7 +117,7 @@ static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len, } else if (nc_offset + 1 == non_ctxlen) { cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n"); size_of_pad_before_neg_ctxts = 0; - } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE) + } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1) /* has padding, but no SPNEGO blob */ size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1; else diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 26edaeb4245d8c..84850a55c8b7e7 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -5561,7 +5561,7 @@ struct smb_version_values smb20_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, @@ -5583,7 +5583,7 @@ struct smb_version_values smb21_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, @@ -5604,7 +5604,7 @@ struct smb_version_values smb3any_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, @@ -5625,7 +5625,7 @@ struct smb_version_values smbdefault_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, @@ -5646,7 +5646,7 @@ struct smb_version_values smb30_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, @@ -5667,7 +5667,7 @@ struct smb_version_values smb302_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, @@ -5688,7 +5688,7 @@ struct smb_version_values smb311_values = { .header_size = sizeof(struct smb2_sync_hdr), .header_preamble_size = 0, .max_header_size = MAX_SMB2_HDR_SIZE, - .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .read_rsp_size = sizeof(struct smb2_read_rsp), .lock_cmd = SMB2_LOCK, .cap_unix = 0, .cap_nt_find = SMB2_NT_FIND, diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 76679dc4e63288..4aec01841f0f26 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1261,7 +1261,7 @@ SMB2_sess_sendreceive(struct SMB2_sess_data *sess_data) /* Testing shows that buffer offset must be at location of Buffer[0] */ req->SecurityBufferOffset = - cpu_to_le16(sizeof(struct smb2_sess_setup_req) - 1 /* pad */); + cpu_to_le16(sizeof(struct smb2_sess_setup_req)); req->SecurityBufferLength = cpu_to_le16(sess_data->iov[1].iov_len); memset(&rqst, 0, sizeof(struct smb_rqst)); @@ -1760,8 +1760,7 @@ SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree, iov[0].iov_len = total_len - 1; /* Testing shows that buffer offset must be at location of Buffer[0] */ - req->PathOffset = cpu_to_le16(sizeof(struct smb2_tree_connect_req) - - 1 /* pad */); + req->PathOffset = cpu_to_le16(sizeof(struct smb2_tree_connect_req)); req->PathLength = cpu_to_le16(unc_path_len - 2); iov[1].iov_base = unc_path; iov[1].iov_len = unc_path_len; @@ -4676,7 +4675,7 @@ int SMB2_query_directory_init(const unsigned int xid, memcpy(bufptr, &asteriks, len); req->FileNameOffset = - cpu_to_le16(sizeof(struct smb2_query_directory_req) - 1); + cpu_to_le16(sizeof(struct smb2_query_directory_req)); req->FileNameLength = cpu_to_le16(len); /* * BB could be 30 bytes or so longer if we used SMB2 specific @@ -4873,7 +4872,7 @@ SMB2_set_info_init(struct cifs_tcon *tcon, struct TCP_Server_Info *server, req->AdditionalInformation = cpu_to_le32(additional_info); req->BufferOffset = - cpu_to_le16(sizeof(struct smb2_set_info_req) - 1); + cpu_to_le16(sizeof(struct smb2_set_info_req)); req->BufferLength = cpu_to_le32(*size); memcpy(req->Buffer, *data, *size); @@ -5105,9 +5104,9 @@ build_qfs_info_req(struct kvec *iov, struct cifs_tcon *tcon, req->VolatileFileId = volatile_fid; /* 1 for pad */ req->InputBufferOffset = - cpu_to_le16(sizeof(struct smb2_query_info_req) - 1); + cpu_to_le16(sizeof(struct smb2_query_info_req)); req->OutputBufferLength = cpu_to_le32( - outbuf_len + sizeof(struct smb2_query_info_rsp) - 1); + outbuf_len + sizeof(struct smb2_query_info_rsp)); iov->iov_base = (char *)req; iov->iov_len = total_len; diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 89a732b31390ea..eaa873175318a0 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -220,7 +220,7 @@ struct smb2_err_rsp { __le16 StructureSize; __le16 Reserved; /* MBZ */ __le32 ByteCount; /* even if zero, at least one byte follows */ - __u8 ErrorData[1]; /* variable length */ + __u8 ErrorData[]; /* variable length */ } __packed; #define SYMLINK_ERROR_TAG 0x4c4d5953 @@ -464,7 +464,7 @@ struct smb2_negotiate_rsp { __le16 SecurityBufferOffset; __le16 SecurityBufferLength; __le32 NegotiateContextOffset; /* Pre:SMB3.1.1 was reserved/ignored */ - __u8 Buffer[1]; /* variable length GSS security buffer */ + __u8 Buffer[]; /* variable length GSS security buffer */ } __packed; /* Flags */ @@ -481,7 +481,7 @@ struct smb2_sess_setup_req { __le16 SecurityBufferOffset; __le16 SecurityBufferLength; __u64 PreviousSessionId; - __u8 Buffer[1]; /* variable length GSS security buffer */ + __u8 Buffer[]; /* variable length GSS security buffer */ } __packed; /* Currently defined SessionFlags */ @@ -494,7 +494,7 @@ struct smb2_sess_setup_rsp { __le16 SessionFlags; __le16 SecurityBufferOffset; __le16 SecurityBufferLength; - __u8 Buffer[1]; /* variable length GSS security buffer */ + __u8 Buffer[]; /* variable length GSS security buffer */ } __packed; struct smb2_logoff_req { @@ -520,7 +520,7 @@ struct smb2_tree_connect_req { __le16 Flags; /* Reserved MBZ for dialects prior to SMB3.1.1 */ __le16 PathOffset; __le16 PathLength; - __u8 Buffer[1]; /* variable length */ + __u8 Buffer[]; /* variable length */ } __packed; /* See MS-SMB2 section 2.2.9.2 */ @@ -828,7 +828,7 @@ struct smb2_create_rsp { __u64 VolatileFileId; /* opaque endianness */ __le32 CreateContextsOffset; __le32 CreateContextsLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct create_context { @@ -1289,7 +1289,7 @@ struct smb2_read_plain_req { __le32 RemainingBytes; __le16 ReadChannelInfoOffset; __le16 ReadChannelInfoLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* Read flags */ @@ -1304,7 +1304,7 @@ struct smb2_read_rsp { __le32 DataLength; __le32 DataRemaining; __u32 Flags; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* For write request Flags field below the following flags are defined: */ @@ -1324,7 +1324,7 @@ struct smb2_write_req { __le16 WriteChannelInfoOffset; __le16 WriteChannelInfoLength; __le32 Flags; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_write_rsp { @@ -1335,7 +1335,7 @@ struct smb2_write_rsp { __le32 DataLength; __le32 DataRemaining; __u32 Reserved2; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* notify flags */ @@ -1371,7 +1371,7 @@ struct smb2_change_notify_rsp { __le16 StructureSize; /* Must be 9 */ __le16 OutputBufferOffset; __le32 OutputBufferLength; - __u8 Buffer[1]; /* array of file notify structs */ + __u8 Buffer[]; /* array of file notify structs */ } __packed; #define SMB2_LOCKFLAG_SHARED_LOCK 0x0001 @@ -1394,7 +1394,10 @@ struct smb2_lock_req { __u64 PersistentFileId; /* opaque endianness */ __u64 VolatileFileId; /* opaque endianness */ /* Followed by at least one */ - struct smb2_lock_element locks[1]; + union { + struct smb2_lock_element lock; + DECLARE_FLEX_ARRAY(struct smb2_lock_element, locks); + }; } __packed; struct smb2_lock_rsp { @@ -1434,7 +1437,7 @@ struct smb2_query_directory_req { __le16 FileNameOffset; __le16 FileNameLength; __le32 OutputBufferLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_query_directory_rsp { @@ -1442,7 +1445,7 @@ struct smb2_query_directory_rsp { __le16 StructureSize; /* Must be 9 */ __le16 OutputBufferOffset; __le32 OutputBufferLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* Possible InfoType values */ @@ -1483,7 +1486,7 @@ struct smb2_query_info_req { __le32 Flags; __u64 PersistentFileId; /* opaque endianness */ __u64 VolatileFileId; /* opaque endianness */ - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_query_info_rsp { @@ -1491,7 +1494,7 @@ struct smb2_query_info_rsp { __le16 StructureSize; /* Must be 9 */ __le16 OutputBufferOffset; __le32 OutputBufferLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* @@ -1514,7 +1517,7 @@ struct smb2_set_info_req { __le32 AdditionalInformation; __u64 PersistentFileId; /* opaque endianness */ __u64 VolatileFileId; /* opaque endianness */ - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_set_info_rsp { @@ -1716,7 +1719,10 @@ struct smb2_file_all_info { /* data block encoding of response to level 18 */ __le32 Mode; __le32 AlignmentRequirement; __le32 FileNameLength; - char FileName[1]; + union { + char __pad; /* Legacy structure padding */ + DECLARE_FLEX_ARRAY(char, FileName); + }; } __packed; /* level 18 Query */ struct smb2_file_eof_info { /* encoding of request for level 10 */