From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELtYWfKqMLO+BghTrv9TaS88TZa8L1sN6yVLQ7YkbQ7jxXyFDyFUYf4MM4/NWH7/bkA/5kyw ARC-Seal: i=1; a=rsa-sha256; t=1520528528; cv=none; d=google.com; s=arc-20160816; b=f9S6a4HcmPbj6lNf5AJ3NpUCwg9+grKJaiB/InGCNBdPgjS72TDxHedpVVWj8wo3Jc 8JZKHV0M5CQTMpL6M0bx/rOKyKkp+UyLopTPJX5DYVBENusR9lBI21pWUS9WQVnca2kq +swCBfaZBXeMWSBAeSyCJ1+BMnAhiw4YIyoGRd/dSMp57DkpSgDHyzBi57cDdZfmh+pu rJRTIfDlocgtcQgFXb+eGt7ysu2P6Xj+86xn7snN36Zlyx8UB1a2VDvkYNV6YbKqMeor tnWo4FRIFaaYUpYNUsvu86VoWnwJUzrjqyo2rtko2t2ZqiyCShU8EYonDx4SEQikzGES IdEg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:date:subject:cc:to:from:dkim-signature:delivered-to :list-id:list-subscribe:list-unsubscribe:list-help:list-post :precedence:mailing-list:arc-authentication-results; bh=BAOnLg8xz/HX7iBPazryjgGzDg7+l7+F3AbP7nH4BXY=; b=sAXz6HlHGFLLiNlU//dRWooCRNEfC71QLTmzC59iRWinVDlAyB+Z0xH+YfjE2M/Dxw tcMsz3mYGYWtOWcZeLP0sOQh/cHkcAKo02v7JXAu8cZqT/jcCf2Q5f3d85Y2Dev8BG0W HFZuW5+KB1DjO5Y59WK1fdR5lyj1y+4rOzAdaiC7HBEfn0t8gRyApc1mj4t/mkBEntLh 3J6cfzCo+6Ebf2CBp8s/EpNo3SCWpaUTb6kncPXssuCNrsUXYCnzfjwCjwFsgR7MBnYT wNV7o6DxFCYSkT3c6jJnB6sHnUPUfIONLQeT1SRAtZYw+PAIpbVGElBpNRHqV2KPcao0 MQRA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@tycho-ws.20150623.gappssmtp.com header.s=20150623 header.b=qKanPzRL; spf=pass (google.com: domain of kernel-hardening-return-12238-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12238-gregkh=linuxfoundation.org@lists.openwall.com Authentication-Results: mx.google.com; dkim=pass header.i=@tycho-ws.20150623.gappssmtp.com header.s=20150623 header.b=qKanPzRL; spf=pass (google.com: domain of kernel-hardening-return-12238-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12238-gregkh=linuxfoundation.org@lists.openwall.com Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm List-Post: List-Help: List-Unsubscribe: List-Subscribe: From: Tycho Andersen To: Mimi Zohar , Dmitry Kasatkin Cc: linux-ima-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com, Tycho Andersen Subject: [PATCH] ima: drop vla in ima_audit_measurement() Date: Thu, 8 Mar 2018 10:00:51 -0700 Message-Id: <20180308170051.30840-1-tycho@tycho.ws> X-Mailer: git-send-email 2.14.1 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1594389722092015419?= X-GMAIL-MSGID: =?utf-8?q?1594389722092015419?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: In keeping with the directive to get rid of VLAs [1], let's drop the VLA from ima_audit_measurement(). We need to adjust the return type of ima_audit_measurement, because now this function can fail if an allocation fails. [1]: https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Tycho Andersen --- security/integrity/ima/ima.h | 4 ++-- security/integrity/ima/ima_api.c | 31 +++++++++++++++++++++++-------- security/integrity/ima/ima_main.c | 7 +++++-- 3 files changed, 30 insertions(+), 12 deletions(-) diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index d52b487ad259..8e2470f72f7f 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -201,8 +201,8 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, const unsigned char *filename, struct evm_ima_xattr_data *xattr_value, int xattr_len, int pcr); -void ima_audit_measurement(struct integrity_iint_cache *iint, - const unsigned char *filename); +int ima_audit_measurement(struct integrity_iint_cache *iint, + const unsigned char *filename); int ima_alloc_init_template(struct ima_event_data *event_data, struct ima_template_entry **entry); int ima_store_template(struct ima_template_entry *entry, int violation, diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index 08fe405338e1..008d3887ae00 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -304,17 +304,28 @@ void ima_store_measurement(struct integrity_iint_cache *iint, ima_free_template_entry(entry); } -void ima_audit_measurement(struct integrity_iint_cache *iint, - const unsigned char *filename) +int ima_audit_measurement(struct integrity_iint_cache *iint, + const unsigned char *filename) { struct audit_buffer *ab; - char hash[(iint->ima_hash->length * 2) + 1]; + char *hash, *algo_hash; const char *algo_name = hash_algo_name[iint->ima_hash->algo]; - char algo_hash[sizeof(hash) + strlen(algo_name) + 2]; - int i; + int i, hash_len, algo_hash_len; if (iint->flags & IMA_AUDITED) - return; + return 0; + + hash_len = (iint->ima_hash->length * 2) + 1; + hash = kzalloc(hash_len, GFP_KERNEL); + if (!hash) + return -ENOMEM; + + algo_hash_len = hash_len + strlen(algo_name) + 2; + algo_hash = kzalloc(algo_hash_len, GFP_KERNEL); + if (!algo_hash) { + kfree(hash); + return -ENOMEM; + } for (i = 0; i < iint->ima_hash->length; i++) hex_byte_pack(hash + (i * 2), iint->ima_hash->digest[i]); @@ -323,18 +334,22 @@ void ima_audit_measurement(struct integrity_iint_cache *iint, ab = audit_log_start(current->audit_context, GFP_KERNEL, AUDIT_INTEGRITY_RULE); if (!ab) - return; + goto out; audit_log_format(ab, "file="); audit_log_untrustedstring(ab, filename); audit_log_format(ab, " hash="); - snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash); + snprintf(algo_hash, algo_hash_len, "%s:%s", algo_name, hash); audit_log_untrustedstring(ab, algo_hash); audit_log_task_info(ab, current); audit_log_end(ab); iint->flags |= IMA_AUDITED; +out: + kfree(hash); + kfree(algo_hash); + return 0; } /* diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 2cfb0c714967..356faae6f09c 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -288,8 +288,11 @@ static int process_measurement(struct file *file, char *buf, loff_t size, xattr_value, xattr_len, opened); inode_unlock(inode); } - if (action & IMA_AUDIT) - ima_audit_measurement(iint, pathname); + if (action & IMA_AUDIT) { + rc = ima_audit_measurement(iint, pathname); + if (rc < 0) + goto out_locked; + } if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO)) rc = 0; -- 2.14.1