From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from omta040.useast.a.cloudfilter.net (omta040.useast.a.cloudfilter.net [44.202.169.39]) (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 C1AC639FD8 for ; Tue, 19 Mar 2024 18:44:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=44.202.169.39 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710873856; cv=none; b=W+NK2KrpSkUHJSNxfda1cgoAsRDIuq1s4JRz3ic3n2mKTDYZ0ytBUlp8xP1RLySZF8o+Tmgo2ZhjkSP+j4sPmiFf7C/u7H4KtIIG6r1S9/DqDQc57zKwaYsDWbN4xpgVYGpbN03/mEcbHxSTgZSRQTlKiQMb/jIwgt+bNSrd6UQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710873856; c=relaxed/simple; bh=iYAowg/p3SZt/jzyDoICds4PpBwrKLStcTMZ4bVn/rI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=i64GZDcQeNl/ihLIm+VbdT2YQN/J9gQe0tEVrx1gzsDfTgT+G9AtraA4S86n98U4EvYcjZukQClPhlQ5sRdUie3zdm9tMxxQ0NYR1aeUMZ9KypvDASBqM8j+x0glI3c2UgKEEuQWL6B+GLL4rSRU7r3CspZ1LreY5n94dEcAmzw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=embeddedor.com; spf=pass smtp.mailfrom=embeddedor.com; dkim=pass (2048-bit key) header.d=embeddedor.com header.i=@embeddedor.com header.b=ohl1YzCB; arc=none smtp.client-ip=44.202.169.39 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=embeddedor.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=embeddedor.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=embeddedor.com header.i=@embeddedor.com header.b="ohl1YzCB" Received: from eig-obgw-6010a.ext.cloudfilter.net ([10.0.30.248]) by cmsmtp with ESMTPS id md6zrTyjAl9dRmeRYrLGHD; Tue, 19 Mar 2024 18:44:12 +0000 Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with ESMTPS id meRXrdxrZQufZmeRXrf6js; Tue, 19 Mar 2024 18:44:12 +0000 X-Authority-Analysis: v=2.4 cv=eK4Vjmp1 c=1 sm=1 tr=0 ts=65f9dcfc a=1YbLdUo/zbTtOZ3uB5T3HA==:117 a=UtBFqMlDG83dypD0sxEoAQ==:17 a=IkcTkHD0fZMA:10 a=K6JAEmCyrfEA:10 a=wYkD_t78qR0A:10 a=VwQbUJbxAAAA:8 a=d3QQw60kZKcH4I2Fy2IA:9 a=QEXdDO2ut3YA:10 a=AjGcO6oz07-iQ99wixmX:22 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=embeddedor.com; s=default; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ydgYrx4mSNkCluaznyOIwLt873FVEZ38n23EhvbjbYg=; b=ohl1YzCBoSgJM3bZqMkwrinrCd TJXoN2aGs/7ypt907+FfzadI8+O7PJK1DUjo32eRE5j4xShV0YLhFmYCoTfmBqDer5Sg1NmL3wm3M NpXy383Y4hxJSnhzn3rzVIgdCOZAMuj4gTGkoIqp7EU4lJ6DMkimyA3QXrsvHSysto2jtd9zAKDcz aPxOlGudB99Mg7MenOEkXy4fJPqa2uj1r7PK3vWT9YyBsre+ffHApCf2mRkiv6riMCmk7goCqISq8 fVZSPJS4FSrYsTjxcQPQVz9MfhnbCmnXaXOKvXFvG23FFYrgWdpnqOG2UWrGySG8KN63Mo5ps1UYB llvAOYTQ==; Received: from [201.172.174.229] (port=46584 helo=[192.168.15.10]) by gator4166.hostgator.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.96.2) (envelope-from ) id 1rmeRW-00047P-3C; Tue, 19 Mar 2024 13:44:11 -0500 Message-ID: <626c234a-64ab-4449-a6d8-faeb24dd0abf@embeddedor.com> Date: Tue, 19 Mar 2024 12:44:09 -0600 Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH][next] integrity: Avoid -Wflex-array-member-not-at-end warnings Content-Language: en-US To: "Gustavo A. R. Silva" , Mimi Zohar , Roberto Sassu , Dmitry Kasatkin , Eric Snowberg , Paul Moore , James Morris , "Serge E. Hallyn" Cc: linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, Kees Cook References: From: "Gustavo A. R. Silva" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 201.172.174.229 X-Source-L: No X-Exim-ID: 1rmeRW-00047P-3C X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: ([192.168.15.10]) [201.172.174.229]:46584 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 5 X-Org: HG=hgshared;ORG=hostgator; X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-CMAE-Envelope: MS4xfIAwjhMsSnEdeNxCu5hnoDtB3JsasOoM37yiIfi93VX+WRj0ChbGVu5GfL8V/rvNwq05kYk1d4STn+zrP2M+TQNCeIwPffGU7uenE6f4ys5zVdZ2UzGt xi72mpYj/aJeTh8FZ3XJpKb6KbNbDN+zmBIW32nnm5pY/7Xxp/TQpwNi08rAyU8jpwJ1++HyyeIg3oQhADfHFCvJOLf9AD+aM93LBU/MI+/mveTAC1nDgDJf Hi all, Friendly ping: who can take this, please? :) Thanks! -- Gustavo On 3/4/24 11:52, Gustavo A. R. Silva wrote: > -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting > ready to enable it globally. > > There is currently an object (`hdr)` in `struct ima_max_digest_data` > that contains a flexible structure (`struct ima_digest_data`): > > struct ima_max_digest_data { > struct ima_digest_data hdr; > u8 digest[HASH_MAX_DIGESTSIZE]; > } __packed; > > So, in order to avoid ending up with a flexible-array member in the > middle of another struct, we use the `struct_group_tagged()` helper to > separate the flexible array from the rest of the members in the flexible > structure: > > struct ima_digest_data { > struct_group_tagged(ima_digest_data_hdr, hdr, > > ... the rest of the members > > ); > u8 digest[]; > } __packed; > > With the change described above, we can now declare an object of the > type of the tagged struct, without embedding the flexible array in the > middle of another struct: > > struct ima_max_digest_data { > struct ima_digest_data_hdr hdr; > u8 digest[HASH_MAX_DIGESTSIZE]; > } __packed; > > We also use `container_of()` whenever we need to retrieve a pointer to > the flexible structure. > > So, with these changes, fix the following warnings: > > security/integrity/evm/evm.h:45:32: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > security/integrity/evm/evm.h:45:32: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > security/integrity/evm/evm.h:45:32: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > > Signed-off-by: Gustavo A. R. Silva > --- > security/integrity/ima/ima_api.c | 6 ++++-- > security/integrity/ima/ima_appraise.c | 4 +++- > security/integrity/ima/ima_init.c | 6 ++++-- > security/integrity/ima/ima_main.c | 6 ++++-- > security/integrity/ima/ima_template_lib.c | 10 ++++++---- > security/integrity/integrity.h | 4 +++- > 6 files changed, 24 insertions(+), 12 deletions(-) > > diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c > index b37d043d5748..c7c8d1bffb17 100644 > --- a/security/integrity/ima/ima_api.c > +++ b/security/integrity/ima/ima_api.c > @@ -247,6 +247,8 @@ int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file, > struct inode *real_inode = d_real_inode(file_dentry(file)); > const char *filename = file->f_path.dentry->d_name.name; > struct ima_max_digest_data hash; > + struct ima_digest_data *hash_hdr = container_of(&hash.hdr, > + struct ima_digest_data, hdr); > struct kstat stat; > int result = 0; > int length; > @@ -286,9 +288,9 @@ int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file, > result = -ENODATA; > } > } else if (buf) { > - result = ima_calc_buffer_hash(buf, size, &hash.hdr); > + result = ima_calc_buffer_hash(buf, size, hash_hdr); > } else { > - result = ima_calc_file_hash(file, &hash.hdr); > + result = ima_calc_file_hash(file, hash_hdr); > } > > if (result && result != -EBADF && result != -EINVAL) > diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c > index 3497741caea9..656c709b974f 100644 > --- a/security/integrity/ima/ima_appraise.c > +++ b/security/integrity/ima/ima_appraise.c > @@ -378,7 +378,9 @@ static int xattr_verify(enum ima_hooks func, struct ima_iint_cache *iint, > } > > rc = calc_file_id_hash(IMA_VERITY_DIGSIG, iint->ima_hash->algo, > - iint->ima_hash->digest, &hash.hdr); > + iint->ima_hash->digest, > + container_of(&hash.hdr, > + struct ima_digest_data, hdr)); > if (rc) { > *cause = "sigv3-hashing-error"; > *status = INTEGRITY_FAIL; > diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c > index 393f5c7912d5..4e208239a40e 100644 > --- a/security/integrity/ima/ima_init.c > +++ b/security/integrity/ima/ima_init.c > @@ -48,12 +48,14 @@ static int __init ima_add_boot_aggregate(void) > struct ima_event_data event_data = { .iint = iint, > .filename = boot_aggregate_name }; > struct ima_max_digest_data hash; > + struct ima_digest_data *hash_hdr = container_of(&hash.hdr, > + struct ima_digest_data, hdr); > int result = -ENOMEM; > int violation = 0; > > memset(iint, 0, sizeof(*iint)); > memset(&hash, 0, sizeof(hash)); > - iint->ima_hash = &hash.hdr; > + iint->ima_hash = hash_hdr; > iint->ima_hash->algo = ima_hash_algo; > iint->ima_hash->length = hash_digest_size[ima_hash_algo]; > > @@ -70,7 +72,7 @@ static int __init ima_add_boot_aggregate(void) > * is not found. > */ > if (ima_tpm_chip) { > - result = ima_calc_boot_aggregate(&hash.hdr); > + result = ima_calc_boot_aggregate(hash_hdr); > if (result < 0) { > audit_cause = "hashing_error"; > goto err_out; > diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c > index c84e8c55333d..0d3a7c864fd4 100644 > --- a/security/integrity/ima/ima_main.c > +++ b/security/integrity/ima/ima_main.c > @@ -941,6 +941,8 @@ int process_buffer_measurement(struct mnt_idmap *idmap, > .buf_len = size}; > struct ima_template_desc *template; > struct ima_max_digest_data hash; > + struct ima_digest_data *hash_hdr = container_of(&hash.hdr, > + struct ima_digest_data, hdr); > char digest_hash[IMA_MAX_DIGEST_SIZE]; > int digest_hash_len = hash_digest_size[ima_hash_algo]; > int violation = 0; > @@ -979,7 +981,7 @@ int process_buffer_measurement(struct mnt_idmap *idmap, > if (!pcr) > pcr = CONFIG_IMA_MEASURE_PCR_IDX; > > - iint.ima_hash = &hash.hdr; > + iint.ima_hash = hash_hdr; > iint.ima_hash->algo = ima_hash_algo; > iint.ima_hash->length = hash_digest_size[ima_hash_algo]; > > @@ -990,7 +992,7 @@ int process_buffer_measurement(struct mnt_idmap *idmap, > } > > if (buf_hash) { > - memcpy(digest_hash, hash.hdr.digest, digest_hash_len); > + memcpy(digest_hash, hash_hdr->digest, digest_hash_len); > > ret = ima_calc_buffer_hash(digest_hash, digest_hash_len, > iint.ima_hash); > diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c > index 6cd0add524cd..74198d7619da 100644 > --- a/security/integrity/ima/ima_template_lib.c > +++ b/security/integrity/ima/ima_template_lib.c > @@ -339,6 +339,8 @@ int ima_eventdigest_init(struct ima_event_data *event_data, > struct ima_field_data *field_data) > { > struct ima_max_digest_data hash; > + struct ima_digest_data *hash_hdr = container_of(&hash.hdr, > + struct ima_digest_data, hdr); > u8 *cur_digest = NULL; > u32 cur_digestsize = 0; > struct inode *inode; > @@ -358,7 +360,7 @@ int ima_eventdigest_init(struct ima_event_data *event_data, > if ((const char *)event_data->filename == boot_aggregate_name) { > if (ima_tpm_chip) { > hash.hdr.algo = HASH_ALGO_SHA1; > - result = ima_calc_boot_aggregate(&hash.hdr); > + result = ima_calc_boot_aggregate(hash_hdr); > > /* algo can change depending on available PCR banks */ > if (!result && hash.hdr.algo != HASH_ALGO_SHA1) > @@ -368,7 +370,7 @@ int ima_eventdigest_init(struct ima_event_data *event_data, > memset(&hash, 0, sizeof(hash)); > } > > - cur_digest = hash.hdr.digest; > + cur_digest = hash_hdr->digest; > cur_digestsize = hash_digest_size[HASH_ALGO_SHA1]; > goto out; > } > @@ -379,14 +381,14 @@ int ima_eventdigest_init(struct ima_event_data *event_data, > inode = file_inode(event_data->file); > hash.hdr.algo = ima_template_hash_algo_allowed(ima_hash_algo) ? > ima_hash_algo : HASH_ALGO_SHA1; > - result = ima_calc_file_hash(event_data->file, &hash.hdr); > + result = ima_calc_file_hash(event_data->file, hash_hdr); > if (result) { > integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, > event_data->filename, "collect_data", > "failed", result, 0); > return result; > } > - cur_digest = hash.hdr.digest; > + cur_digest = hash_hdr->digest; > cur_digestsize = hash.hdr.length; > out: > return ima_eventdigest_init_common(cur_digest, cur_digestsize, > diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h > index 50d6f798e613..fc1952da02ea 100644 > --- a/security/integrity/integrity.h > +++ b/security/integrity/integrity.h > @@ -44,6 +44,7 @@ struct evm_xattr { > #define IMA_MAX_DIGEST_SIZE HASH_MAX_DIGESTSIZE > > struct ima_digest_data { > + struct_group_tagged(ima_digest_data_hdr, hdr, > u8 algo; > u8 length; > union { > @@ -57,6 +58,7 @@ struct ima_digest_data { > } ng; > u8 data[2]; > } xattr; > + ); > u8 digest[]; > } __packed; > > @@ -65,7 +67,7 @@ struct ima_digest_data { > * with the maximum hash size, define ima_max_digest_data struct. > */ > struct ima_max_digest_data { > - struct ima_digest_data hdr; > + struct ima_digest_data_hdr hdr; > u8 digest[HASH_MAX_DIGESTSIZE]; > } __packed; >