Commit 26630dd8 authored by GUO Zihua's avatar GUO Zihua Committed by Zheng Zengkai
Browse files

ima: Simplify ima_lsm_copy_rule 

maillist inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I61O87
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=d57378d3aa4d864d9e590482602068af1b20c0c5



--------------------------------

Currently ima_lsm_copy_rule() set the arg_p field of the source rule to
NULL, so that the source rule could be freed afterward. It does not make
sense for this behavior to be inside a "copy" function. So move it
outside and let the caller handle this field.

ima_lsm_copy_rule() now produce a shallow copy of the original entry
including args_p field. Meaning only the lsm.rule and the rule itself
should be freed for the original rule. Thus, instead of calling
ima_lsm_free_rule() which frees lsm.rule as well as args_p field, free
the lsm.rule directly.

Signed-off-by: default avatarGUO Zihua <guozihua@huawei.com>
Reviewed-by: default avatarRoberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: default avatarMimi Zohar <zohar@linux.ibm.com>
Conflicts:
	security/integrity/ima/ima_policy.c
Signed-off-by: default avatarGUO Zihua <guozihua@huawei.com>
Reviewed-by: default avatarXiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: default avatarGUO Zihua <guozihua@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent d4e9835a

security/integrity/ima/ima_policy.c

+3 −7
Original line number Diff line number Diff line
@@ -399,12 +399,6 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) 


		nentry->lsm[i].type = entry->lsm[i].type;

		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;



		ima_filter_rule_init(nentry->lsm[i].type, Audit_equal,

				     nentry->lsm[i].args_p,
@@ -418,6 +412,7 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) 


static int ima_lsm_update_rule(struct ima_rule_entry *entry)

{

	int i;

	struct ima_rule_entry *nentry;



	nentry = ima_lsm_copy_rule(entry);
@@ -432,7 +427,8 @@ static int ima_lsm_update_rule(struct ima_rule_entry *entry) 
	 * references and the entry itself. All other memory refrences will now

	 * be owned by nentry.

	 */

	ima_lsm_free_rule(entry);

	for (i = 0; i < MAX_LSM_RULES; i++)

		ima_filter_rule_free(entry->lsm[i].rule);

	kfree(entry);



	return 0;