This is a note to let you know that I've just added the patch titled
IMA: use vfs_getattr_nosec to get the i_version
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ima-use-vfs_getattr_nosec-to-get-the-i_version.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6169658018937657f61d2ef9127d38476faafb14
Author: Jeff Layton <jlayton@xxxxxxxxxx>
Date: Mon Apr 17 12:55:51 2023 -0400
IMA: use vfs_getattr_nosec to get the i_version
[ Upstream commit db1d1e8b9867aae5c3e61ad7859abfcc4a6fd6c7 ]
IMA currently accesses the i_version out of the inode directly when it
does a measurement. This is fine for most simple filesystems, but can be
problematic with more complex setups (e.g. overlayfs).
Make IMA instead call vfs_getattr_nosec to get this info. This allows
the filesystem to determine whether and how to report the i_version, and
should allow IMA to work properly with a broader class of filesystems in
the future.
Reported-and-Tested-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
Reviewed-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 026c8c9db9920..7a244e8ce65a5 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -13,7 +13,6 @@
#include <linux/fs.h>
#include <linux/xattr.h>
#include <linux/evm.h>
-#include <linux/iversion.h>
#include <linux/fsverity.h>
#include "ima.h"
@@ -246,10 +245,11 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
struct inode *real_inode = d_real_inode(file_dentry(file));
const char *filename = file->f_path.dentry->d_name.name;
struct ima_max_digest_data hash;
+ struct kstat stat;
int result = 0;
int length;
void *tmpbuf;
- u64 i_version;
+ u64 i_version = 0;
/*
* Always collect the modsig, because IMA might have already collected
@@ -268,7 +268,10 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
* to an initial measurement/appraisal/audit, but was modified to
* assume the file changed.
*/
- i_version = inode_query_iversion(inode);
+ result = vfs_getattr_nosec(&file->f_path, &stat, STATX_CHANGE_COOKIE,
+ AT_STATX_SYNC_AS_STAT);
+ if (!result && (stat.result_mask & STATX_CHANGE_COOKIE))
+ i_version = stat.change_cookie;
hash.hdr.algo = algo;
hash.hdr.length = hash_digest_size[algo];
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 185666d90eebc..bba421f617312 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -24,7 +24,6 @@
#include <linux/slab.h>
#include <linux/xattr.h>
#include <linux/ima.h>
-#include <linux/iversion.h>
#include <linux/fs.h>
#include <linux/iversion.h>
@@ -164,11 +163,16 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint,
mutex_lock(&iint->mutex);
if (atomic_read(&inode->i_writecount) == 1) {
+ struct kstat stat;
+
update = test_and_clear_bit(IMA_UPDATE_XATTR,
&iint->atomic_flags);
- if (!IS_I_VERSION(inode) ||
- !inode_eq_iversion(inode, iint->version) ||
- (iint->flags & IMA_NEW_FILE)) {
+ if ((iint->flags & IMA_NEW_FILE) ||
+ vfs_getattr_nosec(&file->f_path, &stat,
+ STATX_CHANGE_COOKIE,
+ AT_STATX_SYNC_AS_STAT) ||
+ !(stat.result_mask & STATX_CHANGE_COOKIE) ||
+ stat.change_cookie != iint->version) {
iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
iint->measured_pcrs = 0;
if (update)
