IMA: update ima_counts_put
- As ima_counts_put() may be called after the inode has been freed,
verify that the inode is not NULL, before dereferencing it.
- Maintain the IMA file counters in may_open() properly, decrementing
any counter increments on subsequent errors.
Reported-by: Ciprian Docan <docan@eden.rutgers.edu>
Reported-by: J.R. Okajima <hooanon05@yahoo.co.jp>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/fs/namei.c b/fs/namei.c
index f3c5b27..1f13751 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1542,28 +1542,31 @@
* An append-only file must be opened in append mode for writing.
*/
if (IS_APPEND(inode)) {
+ error = -EPERM;
if ((flag & FMODE_WRITE) && !(flag & O_APPEND))
- return -EPERM;
+ goto err_out;
if (flag & O_TRUNC)
- return -EPERM;
+ goto err_out;
}
/* O_NOATIME can only be set by the owner or superuser */
if (flag & O_NOATIME)
- if (!is_owner_or_cap(inode))
- return -EPERM;
+ if (!is_owner_or_cap(inode)) {
+ error = -EPERM;
+ goto err_out;
+ }
/*
* Ensure there are no outstanding leases on the file.
*/
error = break_lease(inode, flag);
if (error)
- return error;
+ goto err_out;
if (flag & O_TRUNC) {
error = get_write_access(inode);
if (error)
- return error;
+ goto err_out;
/*
* Refuse to truncate files with mandatory locks held on them.
@@ -1581,12 +1584,17 @@
}
put_write_access(inode);
if (error)
- return error;
+ goto err_out;
} else
if (flag & FMODE_WRITE)
vfs_dq_init(inode);
return 0;
+err_out:
+ ima_counts_put(path, acc_mode ?
+ acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) :
+ ACC_MODE(flag) & (MAY_READ | MAY_WRITE));
+ return error;
}
/*