^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) 2012 Red Hat, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/efi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/ctype.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/kmemleak.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/uuid.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include "internal.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) struct inode *efivarfs_get_inode(struct super_block *sb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) const struct inode *dir, int mode,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) dev_t dev, bool is_removable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct inode *inode = new_inode(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) if (inode) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) inode->i_ino = get_next_ino();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) inode->i_mode = mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) inode->i_flags = is_removable ? 0 : S_IMMUTABLE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) switch (mode & S_IFMT) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) case S_IFREG:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) inode->i_fop = &efivarfs_file_operations;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) case S_IFDIR:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) inode->i_op = &efivarfs_dir_inode_operations;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) inode->i_fop = &simple_dir_operations;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) inc_nlink(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) return inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) * Return true if 'str' is a valid efivarfs filename of the form,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) * VariableName-12345678-1234-1234-1234-1234567891bc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) bool efivarfs_valid_name(const char *str, int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) const char *s = str + len - EFI_VARIABLE_GUID_LEN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * We need a GUID, plus at least one letter for the variable name,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * plus the '-' separator
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) if (len < EFI_VARIABLE_GUID_LEN + 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) /* GUID must be preceded by a '-' */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) if (*(s - 1) != '-')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) * Validate that 's' is of the correct format, e.g.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * 12345678-1234-1234-1234-123456789abc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) return uuid_is_valid(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) static int efivarfs_create(struct inode *dir, struct dentry *dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) umode_t mode, bool excl)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) struct inode *inode = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) struct efivar_entry *var;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) int namelen, i = 0, err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) bool is_removable = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) if (!efivarfs_valid_name(dentry->d_name.name, dentry->d_name.len))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) var = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) if (!var)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /* length of the variable name itself: remove GUID and separator */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) namelen = dentry->d_name.len - EFI_VARIABLE_GUID_LEN - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) err = guid_parse(dentry->d_name.name + namelen + 1, &var->var.VendorGuid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) if (efivar_variable_is_removable(var->var.VendorGuid,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) dentry->d_name.name, namelen))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) is_removable = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) inode = efivarfs_get_inode(dir->i_sb, dir, mode, 0, is_removable);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) if (!inode) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) for (i = 0; i < namelen; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) var->var.VariableName[i] = dentry->d_name.name[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) var->var.VariableName[i] = '\0';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) inode->i_private = var;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) kmemleak_ignore(var);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) err = efivar_entry_add(var, &efivarfs_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) d_instantiate(dentry, inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) dget(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) kfree(var);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) if (inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) iput(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) static int efivarfs_unlink(struct inode *dir, struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) struct efivar_entry *var = d_inode(dentry)->i_private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) if (efivar_entry_delete(var))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) drop_nlink(d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) dput(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) const struct inode_operations efivarfs_dir_inode_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) .lookup = simple_lookup,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) .unlink = efivarfs_unlink,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) .create = efivarfs_create,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) };
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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