Linux-Integrity Archive on lore.kernel.org
 help / color / Atom feed
From: Tyler Hicks <tyhicks@linux.microsoft.com>
To: Mimi Zohar <zohar@linux.ibm.com>,
	Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: James Morris <jmorris@namei.org>,
	"Serge E . Hallyn" <serge@hallyn.com>,
	Lakshmi Ramasubramanian <nramas@linux.microsoft.com>,
	Prakhar Srivastava <prsriva02@gmail.com>,
	linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org,
	linux-security-module@vger.kernel.org
Subject: [PATCH v2 07/11] ima: Shallow copy the args_p member of ima_rule_entry.lsm elements
Date: Fri, 26 Jun 2020 17:38:56 -0500
Message-ID: <20200626223900.253615-8-tyhicks@linux.microsoft.com> (raw)
In-Reply-To: <20200626223900.253615-1-tyhicks@linux.microsoft.com>

The args_p member is a simple string that is allocated by
ima_rule_init(). Shallow copy it like other non-LSM references in
ima_rule_entry structs.

There are no longer any necessary error path cleanups to do in
ima_lsm_copy_rule().

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
---

* v2
  - Adjusted context to account for ima_lsm_copy_rule() directly calling
    ima_lsm_free_rule() and the lack of explicit reference ownership
    transfers
  - Added comment to ima_lsm_copy_rule() to document the args_p
    reference ownership transfer

 security/integrity/ima/ima_policy.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index f9b1bdb897da..ef69c54266c6 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -300,10 +300,13 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry)
 			continue;
 
 		nentry->lsm[i].type = entry->lsm[i].type;
-		nentry->lsm[i].args_p = kstrdup(entry->lsm[i].args_p,
-						GFP_KERNEL);
-		if (!nentry->lsm[i].args_p)
-			goto out_err;
+		nentry->lsm[i].args_p = entry->lsm[i].args_p;
+		/*
+		 * Remove the reference from entry so that the associated
+		 * memory will not be freed during a later call to
+		 * ima_lsm_free_rule(entry).
+		 */
+		entry->lsm[i].args_p = NULL;
 
 		security_filter_rule_init(nentry->lsm[i].type,
 					  Audit_equal,
@@ -314,11 +317,6 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry)
 				(char *)entry->lsm[i].args_p);
 	}
 	return nentry;
-
-out_err:
-	ima_lsm_free_rule(nentry);
-	kfree(nentry);
-	return NULL;
 }
 
 static int ima_lsm_update_rule(struct ima_rule_entry *entry)
-- 
2.25.1


  parent reply index

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-26 22:38 [PATCH v2 00/11] ima: Fix rule parsing bugs and extend KEXEC_CMDLINE rule support Tyler Hicks
2020-06-26 22:38 ` [PATCH v2 01/11] ima: Have the LSM free its audit rule Tyler Hicks
2020-06-26 22:38 ` [PATCH v2 02/11] ima: Free the entire rule when deleting a list of rules Tyler Hicks
2020-06-26 22:38 ` [PATCH v2 03/11] ima: Free the entire rule if it fails to parse Tyler Hicks
2020-06-26 22:38 ` [PATCH v2 04/11] ima: Fail rule parsing when buffer hook functions have an invalid action Tyler Hicks
2020-06-26 22:38 ` [PATCH v2 05/11] ima: Fail rule parsing when the KEXEC_CMDLINE hook is combined with an invalid cond Tyler Hicks
2020-06-27 23:40   ` Lakshmi Ramasubramanian
2020-06-26 22:38 ` [PATCH v2 06/11] ima: Fail rule parsing when the KEY_CHECK " Tyler Hicks
2020-06-27 23:39   ` Lakshmi Ramasubramanian
2020-06-26 22:38 ` Tyler Hicks [this message]
2020-06-26 22:38 ` [PATCH v2 08/11] ima: Use correct type for the args_p member of ima_rule_entry.lsm elements Tyler Hicks
2020-06-26 22:38 ` [PATCH v2 09/11] ima: Move validation of the keyrings conditional into ima_validate_rule() Tyler Hicks
2020-06-27 23:49   ` Lakshmi Ramasubramanian
2020-06-29 14:16     ` Tyler Hicks
2020-06-30 23:07   ` Mimi Zohar
2020-07-02 22:16     ` Tyler Hicks
2020-07-03 14:15       ` Mimi Zohar
2020-07-06 13:18         ` Tyler Hicks
2020-07-07  3:18           ` Mimi Zohar
2020-06-26 22:38 ` [PATCH v2 10/11] ima: Use the common function to detect LSM conditionals in a rule Tyler Hicks
2020-06-26 22:39 ` [PATCH v2 11/11] ima: Support additional conditionals in the KEXEC_CMDLINE hook function Tyler Hicks
2020-06-28  0:03   ` Lakshmi Ramasubramanian
2020-07-01  8:04   ` Dave Young
2020-07-01 14:38     ` Tyler Hicks
2020-07-01  0:29 ` [PATCH v2 00/11] ima: Fix rule parsing bugs and extend KEXEC_CMDLINE rule support Mimi Zohar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200626223900.253615-8-tyhicks@linux.microsoft.com \
    --to=tyhicks@linux.microsoft.com \
    --cc=dmitry.kasatkin@gmail.com \
    --cc=jmorris@namei.org \
    --cc=linux-integrity@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=nramas@linux.microsoft.com \
    --cc=prsriva02@gmail.com \
    --cc=serge@hallyn.com \
    --cc=zohar@linux.ibm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Integrity Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-integrity/0 linux-integrity/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-integrity linux-integrity/ https://lore.kernel.org/linux-integrity \
		linux-integrity@vger.kernel.org
	public-inbox-index linux-integrity

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-integrity


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git