[PATCH v2 07/11] ima: Shallow copy the args_p member of ima_rule_entry.lsm elements
From: Tyler Hicks <hidden>
Date: 2020-06-26 22:40:00
Also in:
linux-integrity, lkml
Subsystem:
extended verification module (evm), integrity measurement architecture (ima), security subsystem, the rest · Maintainers:
Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
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 <redacted>
---
* 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