diff options
| -rw-r--r-- | security/integrity/ima/ima_main.c | 62 |
1 files changed, 53 insertions, 9 deletions
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 16dc57d247d0..a89f44d5e030 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -35,6 +35,55 @@ static int __init hash_setup(char *str) } __setup("ima_hash=", hash_setup); +struct ima_imbalance { + struct hlist_node node; + unsigned long fsmagic; +}; + +/* + * ima_limit_imbalance - emit one imbalance message per filesystem type + * + * Maintain list of filesystem types that do not measure files properly. + * Return false if unknown, true if known. + */ +static bool ima_limit_imbalance(struct file *file) +{ + static DEFINE_SPINLOCK(ima_imbalance_lock); + static HLIST_HEAD(ima_imbalance_list); + + struct super_block *sb = file->f_dentry->d_sb; + struct ima_imbalance *entry; + struct hlist_node *node; + bool found = false; + + rcu_read_lock(); + hlist_for_each_entry_rcu(entry, node, &ima_imbalance_list, node) { + if (entry->fsmagic == sb->s_magic) { + found = true; + break; + } + } + rcu_read_unlock(); + if (found) + goto out; + + entry = kmalloc(sizeof(*entry), GFP_NOFS); + if (!entry) + goto out; + entry->fsmagic = sb->s_magic; + spin_lock(&ima_imbalance_lock); + /* + * we could have raced and something else might have added this fs + * to the list, but we don't really care + */ + hlist_add_head_rcu(&entry->node, &ima_imbalance_list); + spin_unlock(&ima_imbalance_lock); + printk(KERN_INFO "IMA: unmeasured files on fsmagic: %lX\n", + entry->fsmagic); +out: + return found; +} + /* * Update the counts given an fmode_t */ @@ -69,15 +118,10 @@ static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode, } } - if ((iint->opencount < 0) || - (iint->readcount < 0) || - (iint->writecount < 0)) { - static int dumped; - - if (dumped) - return; - dumped = 1; - + if (((iint->opencount < 0) || + (iint->readcount < 0) || + (iint->writecount < 0)) && + !ima_limit_imbalance(file)) { printk(KERN_INFO "%s: open/free imbalance (r:%ld w:%ld o:%ld)\n", __FUNCTION__, iint->readcount, iint->writecount, iint->opencount); |