^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2010 IBM Corporation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Authors:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Mimi Zohar <zohar@us.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * File: evm_secfs.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * - Used to signal when key is on keyring
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * - Get the key and enable EVM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/audit.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/mutex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include "evm.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static struct dentry *evm_dir;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) static struct dentry *evm_init_tpm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) static struct dentry *evm_symlink;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #ifdef CONFIG_EVM_ADD_XATTRS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) static struct dentry *evm_xattrs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static DEFINE_MUTEX(xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static int evm_xattrs_locked;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * evm_read_key - read() for <securityfs>/evm
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * @filp: file pointer, not actually used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * @buf: where to put the result
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * @count: maximum to send along
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * @ppos: where to start
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * Returns number of bytes read or error code, as appropriate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) static ssize_t evm_read_key(struct file *filp, char __user *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) size_t count, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) char temp[80];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) ssize_t rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) if (*ppos != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) sprintf(temp, "%d", (evm_initialized & ~EVM_SETUP_COMPLETE));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * evm_write_key - write() for <securityfs>/evm
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * @file: file pointer, not actually used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * @buf: where to get the data from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * @count: bytes sent
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) * @ppos: where to start
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) * Used to signal that key is on the kernel key ring.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) * - get the integrity hmac key from the kernel key ring
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * - create list of hmac protected extended attributes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * Returns number of bytes written or error code, as appropriate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) static ssize_t evm_write_key(struct file *file, const char __user *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) size_t count, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) unsigned int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) if (!capable(CAP_SYS_ADMIN) || (evm_initialized & EVM_SETUP_COMPLETE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) return -EPERM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) ret = kstrtouint_from_user(buf, count, 0, &i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) /* Reject invalid values */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) if (!i || (i & ~EVM_INIT_MASK) != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * Don't allow a request to enable metadata writes if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) * an HMAC key is loaded.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) if ((i & EVM_ALLOW_METADATA_WRITES) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) (evm_initialized & EVM_INIT_HMAC) != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) return -EPERM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) if (i & EVM_INIT_HMAC) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) ret = evm_init_key();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) if (ret != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /* Forbid further writes after the symmetric key is loaded */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) i |= EVM_SETUP_COMPLETE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) evm_initialized |= i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) /* Don't allow protected metadata modification if a symmetric key
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) * is loaded
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) if (evm_initialized & EVM_INIT_HMAC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) evm_initialized &= ~(EVM_ALLOW_METADATA_WRITES);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) static const struct file_operations evm_key_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) .read = evm_read_key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) .write = evm_write_key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) #ifdef CONFIG_EVM_ADD_XATTRS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) * evm_read_xattrs - read() for <securityfs>/evm_xattrs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) * @filp: file pointer, not actually used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * @buf: where to put the result
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * @count: maximum to send along
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) * @ppos: where to start
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) * Returns number of bytes read or error code, as appropriate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) static ssize_t evm_read_xattrs(struct file *filp, char __user *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) size_t count, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) char *temp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) int offset = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) ssize_t rc, size = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) struct xattr_list *xattr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) if (*ppos != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) rc = mutex_lock_interruptible(&xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) return -ERESTARTSYS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) list_for_each_entry(xattr, &evm_config_xattrnames, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) size += strlen(xattr->name) + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) temp = kmalloc(size + 1, GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) if (!temp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) mutex_unlock(&xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) list_for_each_entry(xattr, &evm_config_xattrnames, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) sprintf(temp + offset, "%s\n", xattr->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) offset += strlen(xattr->name) + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) mutex_unlock(&xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) kfree(temp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) * evm_write_xattrs - write() for <securityfs>/evm_xattrs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) * @file: file pointer, not actually used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) * @buf: where to get the data from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) * @count: bytes sent
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) * @ppos: where to start
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) * Returns number of bytes written or error code, as appropriate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) static ssize_t evm_write_xattrs(struct file *file, const char __user *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) size_t count, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) int len, err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) struct xattr_list *xattr, *tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) struct audit_buffer *ab;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) struct iattr newattrs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) struct inode *inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) if (!capable(CAP_SYS_ADMIN) || evm_xattrs_locked)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) return -EPERM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) if (*ppos != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) if (count > XATTR_NAME_MAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) return -E2BIG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) ab = audit_log_start(audit_context(), GFP_KERNEL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) AUDIT_INTEGRITY_EVM_XATTR);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) if (!ab)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) xattr = kmalloc(sizeof(struct xattr_list), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) if (!xattr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) xattr->name = memdup_user_nul(buf, count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) if (IS_ERR(xattr->name)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) err = PTR_ERR(xattr->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) xattr->name = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) /* Remove any trailing newline */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) len = strlen(xattr->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) if (len && xattr->name[len-1] == '\n')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) xattr->name[len-1] = '\0';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) audit_log_format(ab, "xattr=");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) audit_log_untrustedstring(ab, xattr->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) if (strcmp(xattr->name, ".") == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) evm_xattrs_locked = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) newattrs.ia_mode = S_IFREG | 0440;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) newattrs.ia_valid = ATTR_MODE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) inode = evm_xattrs->d_inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) inode_lock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) err = simple_setattr(evm_xattrs, &newattrs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) inode_unlock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) if (!err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) err = count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) if (strncmp(xattr->name, XATTR_SECURITY_PREFIX,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) XATTR_SECURITY_PREFIX_LEN) != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) err = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) * xattr_list_mutex guards against races in evm_read_xattrs().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) * Entries are only added to the evm_config_xattrnames list
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) * and never deleted. Therefore, the list is traversed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) * using list_for_each_entry_lockless() without holding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) * the mutex in evm_calc_hmac_or_hash(), evm_find_protected_xattrs()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) * and evm_protected_xattr().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) mutex_lock(&xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) list_for_each_entry(tmp, &evm_config_xattrnames, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) if (strcmp(xattr->name, tmp->name) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) err = -EEXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) mutex_unlock(&xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) list_add_tail_rcu(&xattr->list, &evm_config_xattrnames);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) mutex_unlock(&xattr_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) audit_log_format(ab, " res=0");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) audit_log_end(ab);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) audit_log_format(ab, " res=%d", err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) audit_log_end(ab);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) if (xattr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) kfree(xattr->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) kfree(xattr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) static const struct file_operations evm_xattr_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) .read = evm_read_xattrs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) .write = evm_write_xattrs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) static int evm_init_xattrs(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) evm_xattrs = securityfs_create_file("evm_xattrs", 0660, evm_dir, NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) &evm_xattr_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) if (!evm_xattrs || IS_ERR(evm_xattrs))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) static int evm_init_xattrs(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) int __init evm_init_secfs(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) int error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) evm_dir = securityfs_create_dir("evm", integrity_dir);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) if (!evm_dir || IS_ERR(evm_dir))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) evm_init_tpm = securityfs_create_file("evm", 0660,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) evm_dir, NULL, &evm_key_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) if (!evm_init_tpm || IS_ERR(evm_init_tpm)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) error = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) evm_symlink = securityfs_create_symlink("evm", NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) "integrity/evm/evm", NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) if (!evm_symlink || IS_ERR(evm_symlink)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) error = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) if (evm_init_xattrs() != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) error = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) securityfs_remove(evm_symlink);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) securityfs_remove(evm_init_tpm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) securityfs_remove(evm_dir);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags