Commit d0d845a7 authored by Hamza Mahfooz's avatar Hamza Mahfooz Committed by John Johansen
Browse files

apparmor: use per file locks for transactional queries 



As made mention of in commit 1dea3b41 ("apparmor: speed up
transactional queries"), a single lock is currently used to synchronize
transactional queries. We can, use the lock allocated for each file by
VFS instead.

Signed-off-by: default avatarHamza Mahfooz <someguy@effective-light.com>
Signed-off-by: default avatarJohn Johansen <john.johansen@canonical.com>
parent aa4ceed7

security/apparmor/apparmorfs.c

+5 −6
Original line number Diff line number Diff line
@@ -811,8 +811,6 @@ struct multi_transaction { 
};



#define MULTI_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct multi_transaction))

/* TODO: replace with per file lock */

static DEFINE_SPINLOCK(multi_transaction_lock);



static void multi_transaction_kref(struct kref *kref)

{
@@ -846,10 +844,10 @@ static void multi_transaction_set(struct file *file, 
	AA_BUG(n > MULTI_TRANSACTION_LIMIT);



	new->size = n;

	spin_lock(&multi_transaction_lock);

	spin_lock(&file->f_lock);

	old = (struct multi_transaction *) file->private_data;

	file->private_data = new;

	spin_unlock(&multi_transaction_lock);

	spin_unlock(&file->f_lock);

	put_multi_transaction(old);

}
@@ -878,9 +876,10 @@ static ssize_t multi_transaction_read(struct file *file, char __user *buf, 
	struct multi_transaction *t;

	ssize_t ret;



	spin_lock(&multi_transaction_lock);

	spin_lock(&file->f_lock);

	t = get_multi_transaction(file->private_data);

	spin_unlock(&multi_transaction_lock);

	spin_unlock(&file->f_lock);



	if (!t)

		return 0;