[PATCH 2/2] ima: don't measure/appraise files on configfs
From: Frederick Lawler <hidden>
Date: 2026-08-18 19:35:31
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
When IMA appraises/measures a file configfs, it has an opportunity to hold onto the ima_iint_mutex while another file from a different file system is attempting to appraise/measure. This may cause a cyclical lock dependency. Add configfs to the default don't measure/appraise lists, similarly to other pseudo file systems. Reported-by: syzbot+448c2e24b1ceff13ed2a@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/6a77c7cd.b50370da.49fe0.0031.GAE@google.com/ (local) Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Frederick Lawler <redacted> --- security/integrity/ima/ima_policy.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index f79d07bb63c6fc4ba6fe594140de8d59f57e4f0b..68d9a5e6c232ea0678e9f51f105cebecccccb43e 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c@@ -165,7 +165,10 @@ static struct ima_rule_entry dont_measure_rules[] __ro_after_init = { {.action = DONT_MEASURE, .fsmagic = CGROUP2_SUPER_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC}, - {.action = DONT_MEASURE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC} + {.action = DONT_MEASURE, .fsmagic = EFIVARFS_MAGIC, + .flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE, .fsmagic = CONFIGFS_MAGIC, + .flags = IMA_FSMAGIC} }; static struct ima_rule_entry original_measurement_rules[] __ro_after_init = {
@@ -211,6 +214,8 @@ static struct ima_rule_entry default_appraise_rules[] __ro_after_init = { {.action = DONT_APPRAISE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = CGROUP2_SUPER_MAGIC, .flags = IMA_FSMAGIC}, + {.action = DONT_APPRAISE, .fsmagic = CONFIGFS_MAGIC, + .flags = IMA_FSMAGIC}, #ifdef CONFIG_IMA_WRITE_POLICY {.action = APPRAISE, .func = POLICY_CHECK, .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
--
2.43.0