diff options
| -rw-r--r-- | security/selinux/hooks.c | 262 |
1 files changed, 101 insertions, 161 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index caf7ca7abfc1..238907d69e8b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -433,16 +433,17 @@ static void superblock_free_security(struct super_block *sb) kfree(sbsec); } +struct selinux_mnt_opts { + const char *fscontext, *context, *rootcontext, *defcontext; +}; + static void selinux_free_mnt_opts(void *mnt_opts) { - struct security_mnt_opts *opts = mnt_opts; - int i; - - if (opts->mnt_opts) - for (i = 0; i < opts->num_mnt_opts; i++) - kfree(opts->mnt_opts[i]); - kfree(opts->mnt_opts); - kfree(opts->mnt_opts_flags); + struct selinux_mnt_opts *opts = mnt_opts; + kfree(opts->fscontext); + kfree(opts->context); + kfree(opts->rootcontext); + kfree(opts->defcontext); kfree(opts); } @@ -624,6 +625,17 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag, return 0; } +static int parse_sid(struct super_block *sb, const char *s, u32 *sid) +{ + int rc = security_context_str_to_sid(&selinux_state, s, + sid, GFP_KERNEL); + if (rc) + pr_warn("SELinux: security_context_str_to_sid" + "(%s) failed for (dev %s, type %s) errno=%d\n", + s, sb->s_id, sb->s_type->name, rc); + return rc; +} + /* * Allow filesystems with binary mount data to explicitly set mount point * labeling information. @@ -634,22 +646,18 @@ static int selinux_set_mnt_opts(struct super_block *sb, unsigned long *set_kern_flags) { const struct cred *cred = current_cred(); - int rc = 0, i; struct superblock_security_struct *sbsec = sb->s_security; - const char *name = sb->s_type->name; struct dentry *root = sbsec->sb->s_root; + struct selinux_mnt_opts *opts = mnt_opts; struct inode_security_struct *root_isec; u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; u32 defcontext_sid = 0; - struct security_mnt_opts *opts = mnt_opts; - char **mount_options = opts ? opts->mnt_opts : NULL; - int *flags = opts ? opts->mnt_opts_flags : NULL; - int num_opts = opts ? opts->num_mnt_opts : 0; + int rc = 0; mutex_lock(&sbsec->lock); if (!selinux_state.initialized) { - if (!num_opts) { + if (!opts) { /* Defer initialization until selinux_complete_init, after the initial policy is loaded and the security server is ready to handle calls. */ @@ -679,7 +687,7 @@ static int selinux_set_mnt_opts(struct super_block *sb, * will be used for both mounts) */ if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) - && (num_opts == 0)) + && !opts) goto out; root_isec = backing_inode_security_novalidate(root); @@ -689,68 +697,48 @@ static int selinux_set_mnt_opts(struct super_block *sb, * also check if someone is trying to mount the same sb more * than once with different security options. */ - for (i = 0; i < num_opts; i++) { - u32 sid; - - if (flags[i] == SBLABEL_MNT) - continue; - rc = security_context_str_to_sid(&selinux_state, - mount_options[i], &sid, - GFP_KERNEL); - if (rc) { - pr_warn("SELinux: security_context_str_to_sid" - "(%s) failed for (dev %s, type %s) errno=%d\n", - mount_options[i], sb->s_id, name, rc); - goto out; - } - switch (flags[i]) { - case FSCONTEXT_MNT: - fscontext_sid = sid; - + if (opts) { + if (opts->fscontext) { + rc = parse_sid(sb, opts->fscontext, &fscontext_sid); + if (rc) + goto out; if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, fscontext_sid)) goto out_double_mount; - sbsec->flags |= FSCONTEXT_MNT; - break; - case CONTEXT_MNT: - context_sid = sid; - + } + if (opts->context) { + rc = parse_sid(sb, opts->context, &context_sid); + if (rc) + goto out; if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, context_sid)) goto out_double_mount; - sbsec->flags |= CONTEXT_MNT; - break; - case ROOTCONTEXT_MNT: - rootcontext_sid = sid; - + } + if (opts->rootcontext) { + rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); + if (rc) + goto out; if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, rootcontext_sid)) goto out_double_mount; - sbsec->flags |= ROOTCONTEXT_MNT; - - break; - case DEFCONTEXT_MNT: - defcontext_sid = sid; - + } + if (opts->defcontext) { + rc = parse_sid(sb, opts->defcontext, &defcontext_sid); + if (rc) + goto out; if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, defcontext_sid)) goto out_double_mount; - sbsec->flags |= DEFCONTEXT_MNT; - - break; - default: - rc = -EINVAL; - goto out; } } if (sbsec->flags & SE_SBINITIALIZED) { /* previously mounted with options, but not on this attempt? */ - if ((sbsec->flags & SE_MNTMASK) && !num_opts) + if ((sbsec->flags & SE_MNTMASK) && !opts) goto out_double_mount; rc = 0; goto out; @@ -883,7 +871,8 @@ out: out_double_mount: rc = -EINVAL; pr_warn("SELinux: mount invalid. Same superblock, different " - "security settings for (dev %s, type %s)\n", sb->s_id, name); + "security settings for (dev %s, type %s)\n", sb->s_id, + sb->s_type->name); goto out; } @@ -998,20 +987,9 @@ out: static int selinux_parse_opts_str(char *options, void **mnt_opts) { + struct selinux_mnt_opts *opts = *mnt_opts; char *p; - char *context = NULL, *defcontext = NULL; - char *fscontext = NULL, *rootcontext = NULL; - int rc, num_mnt_opts = 0; - struct security_mnt_opts *opts = *mnt_opts; - - if (!opts) { - opts = kzalloc(sizeof(struct security_mnt_opts), GFP_KERNEL); - *mnt_opts = opts; - if (!opts) - return -ENOMEM; - } - - opts->num_mnt_opts = 0; + int rc; /* Standard string-based options. */ while ((p = strsep(&options, "|")) != NULL) { @@ -1023,54 +1001,60 @@ static int selinux_parse_opts_str(char *options, token = match_token(p, tokens, args); + if (!opts) { + opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); + if (!opts) + return -ENOMEM; + } + switch (token) { case Opt_context: - if (context || defcontext) { + if (opts->context || opts->defcontext) { rc = -EINVAL; pr_warn(SEL_MOUNT_FAIL_MSG); goto out_err; } - context = match_strdup(&args[0]); - if (!context) { + opts->context = match_strdup(&args[0]); + if (!opts->context) { rc = -ENOMEM; goto out_err; } break; case Opt_fscontext: - if (fscontext) { + if (opts->fscontext) { rc = -EINVAL; pr_warn(SEL_MOUNT_FAIL_MSG); goto out_err; } - fscontext = match_strdup(&args[0]); - if (!fscontext) { + opts->fscontext = match_strdup(&args[0]); + if (!opts->fscontext) { rc = -ENOMEM; goto out_err; } break; case Opt_rootcontext: - if (rootcontext) { + if (opts->rootcontext) { rc = -EINVAL; pr_warn(SEL_MOUNT_FAIL_MSG); goto out_err; } - rootcontext = match_strdup(&args[0]); - if (!rootcontext) { + opts->rootcontext = match_strdup(&args[0]); + if (!opts->rootcontext) { rc = -ENOMEM; goto out_err; } break; case Opt_defcontext: - if (context || defcontext) { + if (opts->context || opts->defcontext) { rc = -EINVAL; pr_warn(SEL_MOUNT_FAIL_MSG); goto out_err; } - defcontext = match_strdup(&args[0]); - if (!defcontext) { + opts->defcontext = match_strdup(&args[0]); + if (!opts->defcontext) { rc = -ENOMEM; goto out_err; } @@ -1084,43 +1068,12 @@ static int selinux_parse_opts_str(char *options, } } - - rc = -ENOMEM; - opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); - if (!opts->mnt_opts) - goto out_err; - - opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), - GFP_KERNEL); - if (!opts->mnt_opts_flags) - goto out_err; - - if (fscontext) { - opts->mnt_opts[num_mnt_opts] = fscontext; - opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; - } - if (context) { - opts->mnt_opts[num_mnt_opts] = context; - opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; - } - if (rootcontext) { - opts->mnt_opts[num_mnt_opts] = rootcontext; - opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; - } - if (defcontext) { - opts->mnt_opts[num_mnt_opts] = defcontext; - opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; - } - - opts->num_mnt_opts = num_mnt_opts; + *mnt_opts = opts; return 0; out_err: - security_free_mnt_opts(mnt_opts); - kfree(context); - kfree(defcontext); - kfree(fscontext); - kfree(rootcontext); + if (opts) + selinux_free_mnt_opts(opts); return rc; } @@ -2752,10 +2705,10 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) { - struct security_mnt_opts *opts = mnt_opts; - int i, *flags; - char **mount_options; + struct selinux_mnt_opts *opts = mnt_opts; struct superblock_security_struct *sbsec = sb->s_security; + u32 sid; + int rc; if (!(sbsec->flags & SE_SBINITIALIZED)) return 0; @@ -2763,48 +2716,35 @@ static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) if (!opts) return 0; - mount_options = opts->mnt_opts; - flags = opts->mnt_opts_flags; - - for (i = 0; i < opts->num_mnt_opts; i++) { - u32 sid; - int rc; - - if (flags[i] == SBLABEL_MNT) - continue; - rc = security_context_str_to_sid(&selinux_state, - mount_options[i], &sid, - GFP_KERNEL); - if (rc) { - pr_warn("SELinux: security_context_str_to_sid" - "(%s) failed for (dev %s, type %s) errno=%d\n", - mount_options[i], sb->s_id, sb->s_type->name, rc); + if (opts->fscontext) { + rc = parse_sid(sb, opts->fscontext, &sid); + if (rc) return rc; - } - 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 = backing_inode_security(sb->s_root); - - 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: - return -EINVAL; - } + if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) + goto out_bad_option; + } + if (opts->context) { + rc = parse_sid(sb, opts->context, &sid); + if (rc) + return rc; + if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) + goto out_bad_option; + } + if (opts->rootcontext) { + struct inode_security_struct *root_isec; + root_isec = backing_inode_security(sb->s_root); + rc = parse_sid(sb, opts->rootcontext, &sid); + if (rc) + return rc; + if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) + goto out_bad_option; + } + if (opts->defcontext) { + rc = parse_sid(sb, opts->defcontext, &sid); + if (rc) + return rc; + if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) + goto out_bad_option; } return 0; |