This patch renames ima_open_policy() and ima_release_policy() respectively
to ima_open_data_upload() and ima_release_data_upload(). They will be used
to implement file operations for interfaces allowing to load data from user
space.
A new flag (IMA_POLICY_BUSY) has been defined to prevent concurrent policy
upload.
Signed-off-by: Roberto Sassu <roberto.sa...@huawei.com>
---
security/integrity/ima/ima_fs.c | 58 ++++++++++++++++++++++++---------
1 file changed, 43 insertions(+), 15 deletions(-)
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index 9a10b62e380f..c8bbc56f735e 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -386,9 +386,20 @@ static ssize_t ima_write_data(struct file *file, const
char __user *buf,
}
enum ima_fs_flags {
+ IMA_POLICY_BUSY,
IMA_FS_BUSY,
};
+static enum ima_fs_flags ima_get_dentry_flag(struct dentry *dentry)
+{
+ enum ima_fs_flags flag = IMA_FS_BUSY;
+
+ if (dentry == ima_policy)
+ flag = IMA_POLICY_BUSY;
+
+ return flag;
+}
+
static unsigned long ima_fs_flags;
#ifdef CONFIG_IMA_READ_POLICY
@@ -401,22 +412,32 @@ static const struct seq_operations ima_policy_seqops = {
#endif
/*
- * ima_open_policy: sequentialize access to the policy file
+ * ima_open_data_upload: sequentialize access to the data upload interface
*/
-static int ima_open_policy(struct inode *inode, struct file *filp)
+static int ima_open_data_upload(struct inode *inode, struct file *filp)
{
+ struct dentry *dentry = file_dentry(filp);
+ const struct seq_operations *seq_ops = NULL;
+ enum ima_fs_flags flag = ima_get_dentry_flag(dentry);
+ bool read_allowed = false;
+
+ if (dentry == ima_policy) {
+#ifdef CONFIG_IMA_READ_POLICY
+ read_allowed = true;
+ seq_ops = &ima_policy_seqops;
+#endif
+ }
+
if (!(filp->f_flags & O_WRONLY)) {
-#ifndef CONFIG_IMA_READ_POLICY
- return -EACCES;
-#else
+ if (!read_allowed)
+ return -EACCES;
if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
return -EACCES;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- return seq_open(filp, &ima_policy_seqops);
-#endif
+ return seq_open(filp, seq_ops);
}
- if (test_and_set_bit(IMA_FS_BUSY, &ima_fs_flags))
+ if (test_and_set_bit(flag, &ima_fs_flags))
return -EBUSY;
return 0;
}
@@ -428,13 +449,20 @@ static int ima_open_policy(struct inode *inode, struct
file *filp)
* point to the new policy rules, and remove the securityfs policy file,
* assuming a valid policy.
*/
-static int ima_release_policy(struct inode *inode, struct file *file)
+static int ima_release_data_upload(struct inode *inode, struct file *file)
{
+ struct dentry *dentry = file_dentry(file);
const char *cause = valid_policy ? "completed" : "failed";
+ enum ima_fs_flags flag = ima_get_dentry_flag(dentry);
if ((file->f_flags & O_ACCMODE) == O_RDONLY)
return seq_release(inode, file);
+ if (dentry != ima_policy) {
+ clear_bit(flag, &ima_fs_flags);
+ return 0;
+ }
+
if (valid_policy && ima_check_policy() < 0) {
cause = "failed";
valid_policy = 0;
@@ -447,7 +475,7 @@ static int ima_release_policy(struct inode *inode, struct
file *file)
if (!valid_policy) {
ima_delete_rules();
valid_policy = 1;
- clear_bit(IMA_FS_BUSY, &ima_fs_flags);
+ clear_bit(flag, &ima_fs_flags);
return 0;
}
@@ -456,18 +484,18 @@ static int ima_release_policy(struct inode *inode, struct
file *file)
securityfs_remove(ima_policy);
ima_policy = NULL;
#elif defined(CONFIG_IMA_WRITE_POLICY)
- clear_bit(IMA_FS_BUSY, &ima_fs_flags);
+ clear_bit(flag, &ima_fs_flags);
#elif defined(CONFIG_IMA_READ_POLICY)
inode->i_mode &= ~S_IWUSR;
#endif
return 0;
}
-static const struct file_operations ima_measure_policy_ops = {
- .open = ima_open_policy,
+static const struct file_operations ima_data_upload_ops = {
+ .open = ima_open_data_upload,
.write = ima_write_data,
.read = seq_read,
- .release = ima_release_policy,
+ .release = ima_release_data_upload,
.llseek = generic_file_llseek,
};
@@ -511,7 +539,7 @@ int __init ima_fs_init(void)
ima_policy = securityfs_create_file("policy", POLICY_FILE_FLAGS,
ima_dir, NULL,
- &ima_measure_policy_ops);
+ &ima_data_upload_ops);
if (IS_ERR(ima_policy))
goto out;
--
2.17.1
