linux-kernel - [PATCH v1.2 1/5] IMA: convert i

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue,  2 Nov 2010 13:08:23 -0400
From:	Mimi Zohar <zohar@...ux.vnet.ibm.com>
To:	linux-kernel@...r.kernel.org
Cc:	Mimi Zohar <zohar@...ux.vnet.ibm.com>,
	linux-security-module@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, jmorris@...ei.org,
	akpm@...ux-foundation.org, torvalds@...ux-foundation.org,
	eparis@...hat.com, viro@...iv.linux.org.uk,
	Dave Chinner <david@...morbit.com>,
	Mimi Zohar <zohar@...ibm.com>
Subject: [PATCH v1.2 1/5] IMA: convert i_readcount to atomic

Convert the inode's i_readcount from an unsigned int to atomic.

Signed-off-by: Mimi Zohar <zohar@...ibm.com>
---
 include/linux/fs.h                |    3 +--
 security/integrity/ima/ima_iint.c |    7 ++++---
 security/integrity/ima/ima_main.c |   11 ++++++-----
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 334d68a..442fceb 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -787,8 +787,7 @@ struct inode {
 	unsigned int		i_flags;
 
 #ifdef CONFIG_IMA
-	/* protected by i_lock */
-	unsigned int		i_readcount; /* struct files open RO */
+	atomic_t		i_readcount; /* struct files open RO */
 #endif
 	atomic_t		i_writecount;
 #ifdef CONFIG_SECURITY
diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c
index c442e47..f005355 100644
--- a/security/integrity/ima/ima_iint.c
+++ b/security/integrity/ima/ima_iint.c
@@ -137,10 +137,11 @@ void ima_inode_free(struct inode *inode)
 {
 	struct ima_iint_cache *iint;
 
-	if (inode->i_readcount)
-		printk(KERN_INFO "%s: readcount: %u\n", __func__, inode->i_readcount);
+	if (atomic_read(&inode->i_readcount))
+		printk(KERN_INFO "%s: readcount: %u\n", __func__,
+		       atomic_read(&inode->i_readcount));
 
-	inode->i_readcount = 0;
+	atomic_set(&inode->i_readcount, 0);
 
 	if (!IS_IMA(inode))
 		return;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 203de97..a189197 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -113,7 +113,7 @@ void ima_counts_get(struct file *file)
 		goto out;
 
 	if (mode & FMODE_WRITE) {
-		if (inode->i_readcount && IS_IMA(inode))
+		if (atomic_read(&inode->i_readcount) && IS_IMA(inode))
 			send_tomtou = true;
 		goto out;
 	}
@@ -127,7 +127,7 @@ void ima_counts_get(struct file *file)
 out:
 	/* remember the vfs deals with i_writecount */
 	if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
-		inode->i_readcount++;
+		atomic_inc(&inode->i_readcount);
 
 	spin_unlock(&inode->i_lock);
 
@@ -149,15 +149,16 @@ static void ima_dec_counts(struct inode *inode, struct file *file)
 	assert_spin_locked(&inode->i_lock);
 
 	if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
-		if (unlikely(inode->i_readcount == 0)) {
+	    	if (unlikely(atomic_read(&inode->i_readcount) == 0)) {
 			if (!ima_limit_imbalance(file)) {
 				printk(KERN_INFO "%s: open/free imbalance (r:%u)\n",
-				       __func__, inode->i_readcount);
+				       __func__,
+				       atomic_read(&inode->i_readcount));
 				dump_stack();
 			}
 			return;
 		}
-		inode->i_readcount--;
+		atomic_dec(&inode->i_readcount);
 	}
 }
 
-- 
1.7.2.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/