linux-stable/include/linux/ima.h
Roberto Sassu 1cb936fee7 ima: Align ima_file_mmap() parameters with mmap_file LSM hook
commit 4971c268b8 upstream.

Commit 98de59bfe4 ("take calculation of final prot in
security_mmap_file() into a helper") moved the code to update prot, to be
the actual protections applied to the kernel, to a new helper called
mmap_prot().

However, while without the helper ima_file_mmap() was getting the updated
prot, with the helper ima_file_mmap() gets the original prot, which
contains the protections requested by the application.

A possible consequence of this change is that, if an application calls
mmap() with only PROT_READ, and the kernel applies PROT_EXEC in addition,
that application would have access to executable memory without having this
event recorded in the IMA measurement list. This situation would occur for
example if the application, before mmap(), calls the personality() system
call with READ_IMPLIES_EXEC as the first argument.

Align ima_file_mmap() parameters with those of the mmap_file LSM hook, so
that IMA can receive both the requested prot and the final prot. Since the
requested protections are stored in a new variable, and the final
protections are stored in the existing variable, this effectively restores
the original behavior of the MMAP_CHECK hook.

Cc: stable@vger.kernel.org
Fixes: 98de59bfe4 ("take calculation of final prot in security_mmap_file() into a helper")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10 09:40:03 +01:00

223 lines
5.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2008 IBM Corporation
* Author: Mimi Zohar <zohar@us.ibm.com>
*/
#ifndef _LINUX_IMA_H
#define _LINUX_IMA_H
#include <linux/kernel_read_file.h>
#include <linux/fs.h>
#include <linux/security.h>
#include <linux/kexec.h>
#include <crypto/hash_info.h>
struct linux_binprm;
#ifdef CONFIG_IMA
extern enum hash_algo ima_get_current_hash_algo(void);
extern int ima_bprm_check(struct linux_binprm *bprm);
extern int ima_file_check(struct file *file, int mask);
extern void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
struct inode *inode);
extern void ima_file_free(struct file *file);
extern int ima_file_mmap(struct file *file, unsigned long reqprot,
unsigned long prot, unsigned long flags);
extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot);
extern int ima_load_data(enum kernel_load_data_id id, bool contents);
extern int ima_post_load_data(char *buf, loff_t size,
enum kernel_load_data_id id, char *description);
extern int ima_read_file(struct file *file, enum kernel_read_file_id id,
bool contents);
extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
enum kernel_read_file_id id);
extern void ima_post_path_mknod(struct user_namespace *mnt_userns,
struct dentry *dentry);
extern int ima_file_hash(struct file *file, char *buf, size_t buf_size);
extern int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size);
extern void ima_kexec_cmdline(int kernel_fd, const void *buf, int size);
extern int ima_measure_critical_data(const char *event_label,
const char *event_name,
const void *buf, size_t buf_len,
bool hash, u8 *digest, size_t digest_len);
#ifdef CONFIG_IMA_APPRAISE_BOOTPARAM
extern void ima_appraise_parse_cmdline(void);
#else
static inline void ima_appraise_parse_cmdline(void) {}
#endif
#ifdef CONFIG_IMA_KEXEC
extern void ima_add_kexec_buffer(struct kimage *image);
#endif
#ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
extern bool arch_ima_get_secureboot(void);
extern const char * const *arch_get_ima_policy(void);
#else
static inline bool arch_ima_get_secureboot(void)
{
return false;
}
static inline const char * const *arch_get_ima_policy(void)
{
return NULL;
}
#endif
#else
static inline enum hash_algo ima_get_current_hash_algo(void)
{
return HASH_ALGO__LAST;
}
static inline int ima_bprm_check(struct linux_binprm *bprm)
{
return 0;
}
static inline int ima_file_check(struct file *file, int mask)
{
return 0;
}
static inline void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
struct inode *inode)
{
}
static inline void ima_file_free(struct file *file)
{
return;
}
static inline int ima_file_mmap(struct file *file, unsigned long reqprot,
unsigned long prot, unsigned long flags)
{
return 0;
}
static inline int ima_file_mprotect(struct vm_area_struct *vma,
unsigned long prot)
{
return 0;
}
static inline int ima_load_data(enum kernel_load_data_id id, bool contents)
{
return 0;
}
static inline int ima_post_load_data(char *buf, loff_t size,
enum kernel_load_data_id id,
char *description)
{
return 0;
}
static inline int ima_read_file(struct file *file, enum kernel_read_file_id id,
bool contents)
{
return 0;
}
static inline int ima_post_read_file(struct file *file, void *buf, loff_t size,
enum kernel_read_file_id id)
{
return 0;
}
static inline void ima_post_path_mknod(struct user_namespace *mnt_userns,
struct dentry *dentry)
{
return;
}
static inline int ima_file_hash(struct file *file, char *buf, size_t buf_size)
{
return -EOPNOTSUPP;
}
static inline int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size)
{
return -EOPNOTSUPP;
}
static inline void ima_kexec_cmdline(int kernel_fd, const void *buf, int size) {}
static inline int ima_measure_critical_data(const char *event_label,
const char *event_name,
const void *buf, size_t buf_len,
bool hash, u8 *digest,
size_t digest_len)
{
return -ENOENT;
}
#endif /* CONFIG_IMA */
#ifndef CONFIG_IMA_KEXEC
struct kimage;
static inline void ima_add_kexec_buffer(struct kimage *image)
{}
#endif
#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
extern void ima_post_key_create_or_update(struct key *keyring,
struct key *key,
const void *payload, size_t plen,
unsigned long flags, bool create);
#else
static inline void ima_post_key_create_or_update(struct key *keyring,
struct key *key,
const void *payload,
size_t plen,
unsigned long flags,
bool create) {}
#endif /* CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS */
#ifdef CONFIG_IMA_APPRAISE
extern bool is_ima_appraise_enabled(void);
extern void ima_inode_post_setattr(struct user_namespace *mnt_userns,
struct dentry *dentry);
extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
const void *xattr_value, size_t xattr_value_len);
extern int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name);
#else
static inline bool is_ima_appraise_enabled(void)
{
return 0;
}
static inline void ima_inode_post_setattr(struct user_namespace *mnt_userns,
struct dentry *dentry)
{
return;
}
static inline int ima_inode_setxattr(struct dentry *dentry,
const char *xattr_name,
const void *xattr_value,
size_t xattr_value_len)
{
return 0;
}
static inline int ima_inode_removexattr(struct dentry *dentry,
const char *xattr_name)
{
return 0;
}
#endif /* CONFIG_IMA_APPRAISE */
#if defined(CONFIG_IMA_APPRAISE) && defined(CONFIG_INTEGRITY_TRUSTED_KEYRING)
extern bool ima_appraise_signature(enum kernel_read_file_id func);
#else
static inline bool ima_appraise_signature(enum kernel_read_file_id func)
{
return false;
}
#endif /* CONFIG_IMA_APPRAISE && CONFIG_INTEGRITY_TRUSTED_KEYRING */
#endif /* _LINUX_IMA_H */