seqnum_ops api is introduced to be used when a variable is used as
a sequence/stat counter and doesn't guard object lifetimes. This
clearly differentiates atomic_t usages that guard object lifetimes.
seqnum32 variables wrap around to INT_MIN when it overflows and
should not be used to guard resource lifetimes, device usage and
open counts that control state changes, and pm states.
atomic_t variables used for eima_htable.violations and number of stored
measurements and ios_threshold are atomic counters, and violations is
only an idicator and can overflow. No chane to the behavior with this
change.
Signed-off-by: Shuah Khan <sk...@linuxfoundation.org>
---
security/integrity/ima/ima.h | 5 +++--
security/integrity/ima/ima_api.c | 2 +-
security/integrity/ima/ima_fs.c | 4 ++--
security/integrity/ima/ima_queue.c | 7 ++++---
4 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 6ebefec616e4..55fe1d14c67a 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -21,6 +21,7 @@
#include <linux/tpm.h>
#include <linux/audit.h>
#include <crypto/hash_info.h>
+#include <linux/seqnum_ops.h>
#include "../integrity.h"
@@ -174,8 +175,8 @@ int ima_lsm_policy_change(struct notifier_block *nb,
unsigned long event,
extern spinlock_t ima_queue_lock;
struct ima_h_table {
- atomic_long_t len; /* number of stored measurements in the list */
- atomic_long_t violations;
+ struct seqnum64 len; /* number of stored measurements in the list */
+ struct seqnum64 violations;
struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
};
extern struct ima_h_table ima_htable;
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 4f39fb93f278..b1a203435698 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -144,7 +144,7 @@ void ima_add_violation(struct file *file, const unsigned
char *filename,
int result;
/* can overflow, only indicator */
- atomic_long_inc(&ima_htable.violations);
+ seqnum64_inc(&ima_htable.violations);
result = ima_alloc_init_template(&event_data, &entry, NULL);
if (result < 0) {
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index ea8ff8a07b36..03a78b445052 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -39,12 +39,12 @@ __setup("ima_canonical_fmt", default_canonical_fmt_setup);
static int valid_policy = 1;
static ssize_t ima_show_htable_value(char __user *buf, size_t count,
- loff_t *ppos, atomic_long_t *val)
+ loff_t *ppos, struct seqnum64 *val)
{
char tmpbuf[32]; /* greater than largest 'long' string value */
ssize_t len;
- len = scnprintf(tmpbuf, sizeof(tmpbuf), "%li\n", atomic_long_read(val));
+ len = scnprintf(tmpbuf, sizeof(tmpbuf), "%lli\n", seqnum64_read(val));
return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
}
diff --git a/security/integrity/ima/ima_queue.c
b/security/integrity/ima/ima_queue.c
index c096ef8945c7..87db50dd1721 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -17,6 +17,7 @@
#include <linux/rculist.h>
#include <linux/slab.h>
+#include <linux/seqnum_ops.h>
#include "ima.h"
#define AUDIT_CAUSE_LEN_MAX 32
@@ -33,8 +34,8 @@ static unsigned long binary_runtime_size = ULONG_MAX;
/* key: inode (before secure-hashing a file) */
struct ima_h_table ima_htable = {
- .len = ATOMIC_LONG_INIT(0),
- .violations = ATOMIC_LONG_INIT(0),
+ .len = SEQNUM_INIT(0),
+ .violations = SEQNUM_INIT(0),
.queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT
};
@@ -106,7 +107,7 @@ static int ima_add_digest_entry(struct ima_template_entry
*entry,
INIT_LIST_HEAD(&qe->later);
list_add_tail_rcu(&qe->later, &ima_measurements);
- atomic_long_inc(&ima_htable.len);
+ seqnum64_inc(&ima_htable.len);
if (update_htable) {
key = ima_hash_key(entry->digests[ima_hash_algo_idx].digest);
hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
--
2.27.0
