diff options
| -rw-r--r-- | security/selinux/hooks.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 3decf07b8dc1..f2f3cf2e806d 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2363,6 +2363,91 @@ out: return rc; } +static int selinux_sb_remount(struct super_block *sb, void *data) +{ + int rc, i, *flags; + struct security_mnt_opts opts; + char *secdata, **mount_options; + struct superblock_security_struct *sbsec = sb->s_security; + + if (!(sbsec->flags & SE_SBINITIALIZED)) + return 0; + + if (!data) + return 0; + + if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) + return 0; + + security_init_mnt_opts(&opts); + secdata = alloc_secdata(); + if (!secdata) + return -ENOMEM; + rc = selinux_sb_copy_data(data, secdata); + if (rc) + goto out_free_secdata; + + rc = selinux_parse_opts_str(secdata, &opts); + if (rc) + goto out_free_secdata; + + mount_options = opts.mnt_opts; + flags = opts.mnt_opts_flags; + + for (i = 0; i < opts.num_mnt_opts; i++) { + u32 sid; + size_t len; + + if (flags[i] == SE_SBLABELSUPP) + continue; + len = strlen(mount_options[i]); + rc = security_context_to_sid(mount_options[i], len, &sid); + if (rc) { + printk(KERN_WARNING "SELinux: security_context_to_sid" + "(%s) failed for (dev %s, type %s) errno=%d\n", + mount_options[i], sb->s_id, sb->s_type->name, rc); + goto out_free_opts; + } + rc = -EINVAL; + switch (flags[i]) { + case FSCONTEXT_MNT: + if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) + goto out_bad_option; + break; + case CONTEXT_MNT: + if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) + goto out_bad_option; + break; + case ROOTCONTEXT_MNT: { + struct inode_security_struct *root_isec; + root_isec = sb->s_root->d_inode->i_security; + + if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) + goto out_bad_option; + break; + } + case DEFCONTEXT_MNT: + if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) + goto out_bad_option; + break; + default: + goto out_free_opts; + } + } + + rc = 0; +out_free_opts: + security_free_mnt_opts(&opts); +out_free_secdata: + free_secdata(secdata); + return rc; +out_bad_option: + printk(KERN_WARNING "SELinux: unable to change security options " + "during remount (dev %s, type=%s)\n", sb->s_id, + sb->s_type->name); + goto out_free_opts; +} + static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) { const struct cred *cred = current_cred(); @@ -5356,6 +5441,7 @@ static struct security_operations selinux_ops = { .sb_alloc_security = selinux_sb_alloc_security, .sb_free_security = selinux_sb_free_security, .sb_copy_data = selinux_sb_copy_data, + .sb_remount = selinux_sb_remount, .sb_kern_mount = selinux_sb_kern_mount, .sb_show_options = selinux_sb_show_options, .sb_statfs = selinux_sb_statfs, |