diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 565 |
1 files changed, 419 insertions, 146 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 2fa28c88900..83d06db34d0 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -51,7 +51,9 @@ #include <linux/tty.h> #include <net/icmp.h> #include <net/ip.h> /* for local_port_range[] */ +#include <net/sock.h> #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ +#include <net/inet_connection_sock.h> #include <net/net_namespace.h> #include <net/netlabel.h> #include <linux/uaccess.h> @@ -60,7 +62,7 @@ #include <linux/bitops.h> #include <linux/interrupt.h> #include <linux/netdevice.h> /* for network interface checks */ -#include <linux/netlink.h> +#include <net/netlink.h> #include <linux/tcp.h> #include <linux/udp.h> #include <linux/dccp.h> @@ -93,8 +95,6 @@ #include "audit.h" #include "avc_ss.h" -#define NUM_SEL_MNT_OPTS 5 - extern struct security_operations *security_ops; /* SECMARK reference count */ @@ -106,7 +106,7 @@ int selinux_enforcing; static int __init enforcing_setup(char *str) { unsigned long enforcing; - if (!strict_strtoul(str, 0, &enforcing)) + if (!kstrtoul(str, 0, &enforcing)) selinux_enforcing = enforcing ? 1 : 0; return 1; } @@ -119,7 +119,7 @@ int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; static int __init selinux_enabled_setup(char *str) { unsigned long enabled; - if (!strict_strtoul(str, 0, &enabled)) + if (!kstrtoul(str, 0, &enabled)) selinux_enabled = enabled ? 1 : 0; return 1; } @@ -137,12 +137,28 @@ static struct kmem_cache *sel_inode_cache; * This function checks the SECMARK reference counter to see if any SECMARK * targets are currently configured, if the reference counter is greater than * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is - * enabled, false (0) if SECMARK is disabled. + * enabled, false (0) if SECMARK is disabled. If the always_check_network + * policy capability is enabled, SECMARK is always considered enabled. * */ static int selinux_secmark_enabled(void) { - return (atomic_read(&selinux_secmark_refcount) > 0); + return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); +} + +/** + * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled + * + * Description: + * This function checks if NetLabel or labeled IPSEC is enabled. Returns true + * (1) if any are enabled or false (0) if neither are enabled. If the + * always_check_network policy capability is enabled, peer labeling + * is always considered enabled. + * + */ +static int selinux_peerlbl_enabled(void) +{ + return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); } /* @@ -217,6 +233,14 @@ static int inode_alloc_security(struct inode *inode) return 0; } +static void inode_free_rcu(struct rcu_head *head) +{ + struct inode_security_struct *isec; + + isec = container_of(head, struct inode_security_struct, rcu); + kmem_cache_free(sel_inode_cache, isec); +} + static void inode_free_security(struct inode *inode) { struct inode_security_struct *isec = inode->i_security; @@ -227,8 +251,16 @@ static void inode_free_security(struct inode *inode) list_del_init(&isec->list); spin_unlock(&sbsec->isec_lock); - inode->i_security = NULL; - kmem_cache_free(sel_inode_cache, isec); + /* + * The inode may still be referenced in a path walk and + * a call to selinux_inode_permission() can be made + * after inode_free_security() is called. Ideally, the VFS + * wouldn't do this, but fixing that is a much harder + * job. For now, simply free the i_security via RCU, and + * leave the current inode->i_security pointer intact. + * The inode will be freed after the RCU grace period too. + */ + call_rcu(&isec->rcu, inode_free_rcu); } static int file_alloc_security(struct file *file) @@ -283,13 +315,14 @@ static void superblock_free_security(struct super_block *sb) /* The file system's label must be initialized prior to use. */ -static const char *labeling_behaviors[6] = { +static const char *labeling_behaviors[7] = { "uses xattr", "uses transition SIDs", "uses task SIDs", "uses genfs_contexts", "not configured for labeling", "uses mountpoint labeling", + "uses native labeling", }; static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); @@ -306,8 +339,11 @@ enum { Opt_defcontext = 3, Opt_rootcontext = 4, Opt_labelsupport = 5, + Opt_nextmntopt = 6, }; +#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) + static const match_table_t tokens = { {Opt_context, CONTEXT_STR "%s"}, {Opt_fscontext, FSCONTEXT_STR "%s"}, @@ -352,6 +388,29 @@ static int may_context_mount_inode_relabel(u32 sid, return rc; } +static int selinux_is_sblabel_mnt(struct super_block *sb) +{ + struct superblock_security_struct *sbsec = sb->s_security; + + if (sbsec->behavior == SECURITY_FS_USE_XATTR || + sbsec->behavior == SECURITY_FS_USE_TRANS || + sbsec->behavior == SECURITY_FS_USE_TASK) + return 1; + + /* Special handling for sysfs. Is genfs but also has setxattr handler*/ + if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) + return 1; + + /* + * Special handling for rootfs. Is genfs but supports + * setting SELinux context on in-core inodes. + */ + if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0) + return 1; + + return 0; +} + static int sb_finish_set_opts(struct super_block *sb) { struct superblock_security_struct *sbsec = sb->s_security; @@ -385,8 +444,6 @@ static int sb_finish_set_opts(struct super_block *sb) } } - sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); - if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", sb->s_id, sb->s_type->name); @@ -395,15 +452,9 @@ static int sb_finish_set_opts(struct super_block *sb) sb->s_id, sb->s_type->name, labeling_behaviors[sbsec->behavior-1]); - if (sbsec->behavior == SECURITY_FS_USE_GENFS || - sbsec->behavior == SECURITY_FS_USE_MNTPOINT || - sbsec->behavior == SECURITY_FS_USE_NONE || - sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) - sbsec->flags &= ~SE_SBLABELSUPP; - - /* Special handling for sysfs. Is genfs but also has setxattr handler*/ - if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) - sbsec->flags |= SE_SBLABELSUPP; + sbsec->flags |= SE_SBINITIALIZED; + if (selinux_is_sblabel_mnt(sb)) + sbsec->flags |= SBLABEL_MNT; /* Initialize the root inode. */ rc = inode_doinit_with_dentry(root_inode, root); @@ -457,15 +508,18 @@ static int selinux_get_mnt_opts(const struct super_block *sb, if (!ss_initialized) return -EINVAL; + /* make sure we always check enough bits to cover the mask */ + BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); + tmp = sbsec->flags & SE_MNTMASK; /* count the number of mount options for this sb */ - for (i = 0; i < 8; i++) { + for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { if (tmp & 0x01) opts->num_mnt_opts++; tmp >>= 1; } /* Check if the Label support flag is set */ - if (sbsec->flags & SE_SBLABELSUPP) + if (sbsec->flags & SBLABEL_MNT) opts->num_mnt_opts++; opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); @@ -512,9 +566,9 @@ static int selinux_get_mnt_opts(const struct super_block *sb, opts->mnt_opts[i] = context; opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; } - if (sbsec->flags & SE_SBLABELSUPP) { + if (sbsec->flags & SBLABEL_MNT) { opts->mnt_opts[i] = NULL; - opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; + opts->mnt_opts_flags[i++] = SBLABEL_MNT; } BUG_ON(i != opts->num_mnt_opts); @@ -551,7 +605,9 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag, * labeling information. */ static int selinux_set_mnt_opts(struct super_block *sb, - struct security_mnt_opts *opts) + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags) { const struct cred *cred = current_cred(); int rc = 0, i; @@ -579,6 +635,12 @@ static int selinux_set_mnt_opts(struct super_block *sb, "before the security server is initialized\n"); goto out; } + if (kern_flags && !set_kern_flags) { + /* Specifying internal flags without providing a place to + * place the results is not allowed */ + rc = -EINVAL; + goto out; + } /* * Binary mount data FS will come through this function twice. Once @@ -603,10 +665,10 @@ static int selinux_set_mnt_opts(struct super_block *sb, for (i = 0; i < num_opts; i++) { u32 sid; - if (flags[i] == SE_SBLABELSUPP) + if (flags[i] == SBLABEL_MNT) continue; rc = security_context_to_sid(mount_options[i], - strlen(mount_options[i]), &sid); + strlen(mount_options[i]), &sid, GFP_KERNEL); if (rc) { printk(KERN_WARNING "SELinux: security_context_to_sid" "(%s) failed for (dev %s, type %s) errno=%d\n", @@ -669,14 +731,19 @@ static int selinux_set_mnt_opts(struct super_block *sb, if (strcmp(sb->s_type->name, "proc") == 0) sbsec->flags |= SE_SBPROC; - /* Determine the labeling behavior to use for this filesystem type. */ - rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); - if (rc) { - printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", - __func__, sb->s_type->name, rc); - goto out; + if (!sbsec->behavior) { + /* + * Determine the labeling behavior to use for this + * filesystem type. + */ + rc = security_fs_use(sb); + if (rc) { + printk(KERN_WARNING + "%s: security_fs_use(%s) returned %d\n", + __func__, sb->s_type->name, rc); + goto out; + } } - /* sets the context of the superblock for the fs being mounted. */ if (fscontext_sid) { rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); @@ -691,6 +758,11 @@ static int selinux_set_mnt_opts(struct super_block *sb, * sets the label used on all file below the mountpoint, and will set * the superblock context if not already set. */ + if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { + sbsec->behavior = SECURITY_FS_USE_NATIVE; + *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; + } + if (context_sid) { if (!fscontext_sid) { rc = may_context_mount_sb_relabel(context_sid, sbsec, @@ -722,7 +794,8 @@ static int selinux_set_mnt_opts(struct super_block *sb, } if (defcontext_sid) { - if (sbsec->behavior != SECURITY_FS_USE_XATTR) { + if (sbsec->behavior != SECURITY_FS_USE_XATTR && + sbsec->behavior != SECURITY_FS_USE_NATIVE) { rc = -EINVAL; printk(KERN_WARNING "SELinux: defcontext option is " "invalid for this filesystem type\n"); @@ -750,7 +823,37 @@ out_double_mount: goto out; } -static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, +static int selinux_cmp_sb_context(const struct super_block *oldsb, + const struct super_block *newsb) +{ + struct superblock_security_struct *old = oldsb->s_security; + struct superblock_security_struct *new = newsb->s_security; + char oldflags = old->flags & SE_MNTMASK; + char newflags = new->flags & SE_MNTMASK; + + if (oldflags != newflags) + goto mismatch; + if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) + goto mismatch; + if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) + goto mismatch; + if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) + goto mismatch; + if (oldflags & ROOTCONTEXT_MNT) { + struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security; + struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security; + if (oldroot->sid != newroot->sid) + goto mismatch; + } + return 0; +mismatch: + printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " + "different security settings for (dev %s, " + "type %s)\n", newsb->s_id, newsb->s_type->name); + return -EBUSY; +} + +static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, struct super_block *newsb) { const struct superblock_security_struct *oldsbsec = oldsb->s_security; @@ -765,14 +868,14 @@ static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, * mount options. thus we can safely deal with this superblock later */ if (!ss_initialized) - return; + return 0; /* how can we clone if the old one wasn't set up?? */ BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); - /* if fs is reusing a sb, just let its options stand... */ + /* if fs is reusing a sb, make sure that the contexts match */ if (newsbsec->flags & SE_SBINITIALIZED) - return; + return selinux_cmp_sb_context(oldsb, newsb); mutex_lock(&newsbsec->lock); @@ -805,6 +908,7 @@ static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, sb_finish_set_opts(newsb); mutex_unlock(&newsbsec->lock); + return 0; } static int selinux_parse_opts_str(char *options, @@ -948,7 +1052,7 @@ static int superblock_doinit(struct super_block *sb, void *data) goto out_err; out: - rc = selinux_set_mnt_opts(sb, &opts); + rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); out_err: security_free_mnt_opts(&opts); @@ -982,7 +1086,7 @@ static void selinux_write_opts(struct seq_file *m, case DEFCONTEXT_MNT: prefix = DEFCONTEXT_STR; break; - case SE_SBLABELSUPP: + case SBLABEL_MNT: seq_putc(m, ','); seq_puts(m, LABELSUPP_STR); continue; @@ -1190,6 +1294,8 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent } switch (sbsec->behavior) { + case SECURITY_FS_USE_NATIVE: + break; case SECURITY_FS_USE_XATTR: if (!inode->i_op->getxattr) { isec->sid = sbsec->def_sid; @@ -1312,15 +1418,33 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent isec->sid = sbsec->sid; if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { - if (opt_dentry) { - isec->sclass = inode_mode_to_security_class(inode->i_mode); - rc = selinux_proc_get_sid(opt_dentry, - isec->sclass, - &sid); - if (rc) - goto out_unlock; - isec->sid = sid; - } + /* We must have a dentry to determine the label on + * procfs inodes */ + if (opt_dentry) + /* Called from d_instantiate or + * d_splice_alias. */ + dentry = dget(opt_dentry); + else + /* Called from selinux_complete_init, try to + * find a dentry. */ + dentry = d_find_alias(inode); + /* + * This can be hit on boot when a file is accessed + * before the policy is loaded. When we load policy we + * may find inodes that have no dentry on the + * sbsec->isec_head list. No reason to complain as + * these will get fixed up the next time we go through + * inode_doinit() with a dentry, before these inodes + * could be used again by userspace. + */ + if (!dentry) + goto out_unlock; + isec->sclass = inode_mode_to_security_class(inode->i_mode); + rc = selinux_proc_get_sid(dentry, isec->sclass, &sid); + dput(dentry); + if (rc) + goto out_unlock; + isec->sid = sid; } break; } @@ -1445,7 +1569,7 @@ static int cred_has_capability(const struct cred *cred, rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); if (audit == SECURITY_CAP_AUDIT) { - int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); + int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); if (rc2) return rc2; } @@ -1468,8 +1592,7 @@ static int task_has_system(struct task_struct *tsk, static int inode_has_perm(const struct cred *cred, struct inode *inode, u32 perms, - struct common_audit_data *adp, - unsigned flags) + struct common_audit_data *adp) { struct inode_security_struct *isec; u32 sid; @@ -1482,7 +1605,7 @@ static int inode_has_perm(const struct cred *cred, sid = cred_sid(cred); isec = inode->i_security; - return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags); + return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); } /* Same as inode_has_perm, but pass explicit audit data containing @@ -1497,7 +1620,7 @@ static inline int dentry_has_perm(const struct cred *cred, ad.type = LSM_AUDIT_DATA_DENTRY; ad.u.dentry = dentry; - return inode_has_perm(cred, inode, av, &ad, 0); + return inode_has_perm(cred, inode, av, &ad); } /* Same as inode_has_perm, but pass explicit audit data containing @@ -1512,7 +1635,19 @@ static inline int path_has_perm(const struct cred *cred, ad.type = LSM_AUDIT_DATA_PATH; ad.u.path = *path; - return inode_has_perm(cred, inode, av, &ad, 0); + return inode_has_perm(cred, inode, av, &ad); +} + +/* Same as path_has_perm, but uses the inode from the file struct. */ +static inline int file_path_has_perm(const struct cred *cred, + struct file *file, + u32 av) +{ + struct common_audit_data ad; + + ad.type = LSM_AUDIT_DATA_PATH; + ad.u.path = file->f_path; + return inode_has_perm(cred, file_inode(file), av, &ad); } /* Check whether a task can use an open file descriptor to @@ -1548,7 +1683,7 @@ static int file_has_perm(const struct cred *cred, /* av is zero if only checking access to the descriptor. */ rc = 0; if (av) - rc = inode_has_perm(cred, inode, av, &ad, 0); + rc = inode_has_perm(cred, inode, av, &ad); out: return rc; @@ -1581,7 +1716,7 @@ static int may_create(struct inode *dir, if (rc) return rc; - if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { + if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { rc = security_transition_sid(sid, dsec->sid, tclass, &dentry->d_name, &newsid); if (rc) @@ -1988,11 +2123,13 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm) new_tsec->exec_sid = 0; /* - * Minimize confusion: if no_new_privs and a transition is - * explicitly requested, then fail the exec. + * Minimize confusion: if no_new_privs or nosuid and a + * transition is explicitly requested, then fail the exec. */ if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) return -EPERM; + if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) + return -EACCES; } else { /* Check for a default transition on this program. */ rc = security_transition_sid(old_tsec->sid, isec->sid, @@ -2109,14 +2246,14 @@ static inline void flush_unauthorized_files(const struct cred *cred, struct tty_file_private *file_priv; /* Revalidate access to controlling tty. - Use path_has_perm on the tty path directly rather - than using file_has_perm, as this particular open - file may belong to another process and we are only - interested in the inode-based check here. */ + Use file_path_has_perm on the tty path directly + rather than using file_has_perm, as this particular + open file may belong to another process and we are + only interested in the inode-based check here. */ file_priv = list_first_entry(&tty->tty_files, struct tty_file_private, list); file = file_priv->file; - if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE)) + if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) drop_tty = 1; } spin_unlock(&tty_files_lock); @@ -2369,10 +2506,11 @@ static int selinux_sb_remount(struct super_block *sb, void *data) u32 sid; size_t len; - if (flags[i] == SE_SBLABELSUPP) + if (flags[i] == SBLABEL_MNT) continue; len = strlen(mount_options[i]); - rc = security_context_to_sid(mount_options[i], len, &sid); + rc = security_context_to_sid(mount_options[i], len, &sid, + GFP_KERNEL); if (rc) { printk(KERN_WARNING "SELinux: security_context_to_sid" "(%s) failed for (dev %s, type %s) errno=%d\n", @@ -2483,8 +2621,43 @@ static void selinux_inode_free_security(struct inode *inode) inode_free_security(inode); } +static int selinux_dentry_init_security(struct dentry *dentry, int mode, + struct qstr *name, void **ctx, + u32 *ctxlen) +{ + const struct cred *cred = current_cred(); + struct task_security_struct *tsec; + struct inode_security_struct *dsec; + struct superblock_security_struct *sbsec; + struct inode *dir = dentry->d_parent->d_inode; + u32 newsid; + int rc; + + tsec = cred->security; + dsec = dir->i_security; + sbsec = dir->i_sb->s_security; + + if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { + newsid = tsec->create_sid; + } else { + rc = security_transition_sid(tsec->sid, dsec->sid, + inode_mode_to_security_class(mode), + name, + &newsid); + if (rc) { + printk(KERN_WARNING + "%s: security_transition_sid failed, rc=%d\n", + __func__, -rc); + return rc; + } + } + + return security_sid_to_context(newsid, (char **)ctx, ctxlen); +} + static int selinux_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, char **name, + const struct qstr *qstr, + const char **name, void **value, size_t *len) { const struct task_security_struct *tsec = current_security(); @@ -2492,7 +2665,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, struct superblock_security_struct *sbsec; u32 sid, newsid, clen; int rc; - char *namep = NULL, *context; + char *context; dsec = dir->i_security; sbsec = dir->i_sb->s_security; @@ -2503,7 +2676,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, if ((sbsec->flags & SE_SBINITIALIZED) && (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) newsid = sbsec->mntpoint_sid; - else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { + else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { rc = security_transition_sid(sid, dsec->sid, inode_mode_to_security_class(inode->i_mode), qstr, &newsid); @@ -2525,22 +2698,16 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, isec->initialized = 1; } - if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) + if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) return -EOPNOTSUPP; - if (name) { - namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); - if (!namep) - return -ENOMEM; - *name = namep; - } + if (name) + *name = XATTR_SELINUX_SUFFIX; if (value && len) { rc = security_sid_to_context_force(newsid, &context, &clen); - if (rc) { - kfree(namep); + if (rc) return rc; - } *value = context; *len = clen; } @@ -2605,6 +2772,7 @@ static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *na static noinline int audit_inode_permission(struct inode *inode, u32 perms, u32 audited, u32 denied, + int result, unsigned flags) { struct common_audit_data ad; @@ -2615,7 +2783,7 @@ static noinline int audit_inode_permission(struct inode *inode, ad.u.inode = inode; rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, - audited, denied, &ad, flags); + audited, denied, result, &ad, flags); if (rc) return rc; return 0; @@ -2657,7 +2825,7 @@ static int selinux_inode_permission(struct inode *inode, int mask) if (likely(!audited)) return rc; - rc2 = audit_inode_permission(inode, perms, audited, denied, flags); + rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); if (rc2) return rc2; return rc; @@ -2733,7 +2901,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name, return selinux_inode_setotherxattr(dentry, name); sbsec = inode->i_sb->s_security; - if (!(sbsec->flags & SE_SBLABELSUPP)) + if (!(sbsec->flags & SBLABEL_MNT)) return -EOPNOTSUPP; if (!inode_owner_or_capable(inode)) @@ -2747,7 +2915,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name, if (rc) return rc; - rc = security_context_to_sid(value, size, &newsid); + rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); if (rc == -EINVAL) { if (!capable(CAP_MAC_ADMIN)) { struct audit_buffer *ab; @@ -2817,7 +2985,10 @@ static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, return; } + isec->sclass = inode_mode_to_security_class(inode->i_mode); isec->sid = newsid; + isec->initialized = 1; + return; } @@ -2901,10 +3072,11 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name, if (!value || !size) return -EACCES; - rc = security_context_to_sid((void *)value, size, &newsid); + rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL); if (rc) return rc; + isec->sclass = inode_mode_to_security_class(inode->i_mode); isec->sid = newsid; isec->initialized = 1; return 0; @@ -3054,24 +3226,20 @@ error: static int selinux_mmap_addr(unsigned long addr) { - int rc = 0; - u32 sid = current_sid(); + int rc; + + /* do DAC check on address space usage */ + rc = cap_mmap_addr(addr); + if (rc) + return rc; - /* - * notice that we are intentionally putting the SELinux check before - * the secondary cap_file_mmap check. This is such a likely attempt - * at bad behaviour/exploit that we always want to get the AVC, even - * if DAC would have also denied the operation. - */ if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { + u32 sid = current_sid(); rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, MEMPROTECT__MMAP_ZERO, NULL); - if (rc) - return rc; } - /* do DAC check on address space usage */ - return cap_mmap_addr(addr); + return rc; } static int selinux_mmap_file(struct file *file, unsigned long reqprot, @@ -3152,6 +3320,9 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, case F_GETLK: case F_SETLK: case F_SETLKW: + case F_OFD_GETLK: + case F_OFD_SETLK: + case F_OFD_SETLKW: #if BITS_PER_LONG == 32 case F_GETLK64: case F_SETLK64: @@ -3227,7 +3398,7 @@ static int selinux_file_open(struct file *file, const struct cred *cred) * new inode label or new policy. * This check is not redundant - do not remove. */ - return path_has_perm(cred, &file->f_path, open_file_to_av(file)); + return file_path_has_perm(cred, file, open_file_to_av(file)); } /* task security operations */ @@ -3690,8 +3861,12 @@ static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) u32 nlbl_sid; u32 nlbl_type; - selinux_skb_xfrm_sid(skb, &xfrm_sid); - selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); + err = selinux_xfrm_skb_sid(skb, &xfrm_sid); + if (unlikely(err)) + return -EACCES; + err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); + if (unlikely(err)) + return -EACCES; err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); if (unlikely(err)) { @@ -3704,6 +3879,30 @@ static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) return 0; } +/** + * selinux_conn_sid - Determine the child socket label for a connection + * @sk_sid: the parent socket's SID + * @skb_sid: the packet's SID + * @conn_sid: the resulting connection SID + * + * If @skb_sid is valid then the user:role:type information from @sk_sid is + * combined with the MLS information from @skb_sid in order to create + * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy + * of @sk_sid. Returns zero on success, negative values on failure. + * + */ +static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) +{ + int err = 0; + + if (skb_sid != SECSID_NULL) + err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid); + else + *conn_sid = sk_sid; + + return err; +} + /* socket security operations */ static int socket_sockcreate_sid(const struct task_security_struct *tsec, @@ -3827,7 +4026,7 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in if (snum) { int low, high; - inet_get_local_port_range(&low, &high); + inet_get_local_port_range(sock_net(sk), &low, &high); if (snum < max(PROT_SOCK, low) || snum > high) { err = sel_netport_sid(sk->sk_protocol, @@ -4145,7 +4344,7 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) return selinux_sock_rcv_skb_compat(sk, skb, family); secmark_active = selinux_secmark_enabled(); - peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); + peerlbl_active = selinux_peerlbl_enabled(); if (!secmark_active && !peerlbl_active) return 0; @@ -4171,8 +4370,10 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) } err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, PEER__RECV, &ad); - if (err) + if (err) { selinux_netlbl_err(skb, err, 0); + return err; + } } if (secmark_active) { @@ -4309,27 +4510,18 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, { struct sk_security_struct *sksec = sk->sk_security; int err; - u16 family = sk->sk_family; - u32 newsid; + u16 family = req->rsk_ops->family; + u32 connsid; u32 peersid; - /* handle mapped IPv4 packets arriving via IPv6 sockets */ - if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) - family = PF_INET; - err = selinux_skb_peerlbl_sid(skb, family, &peersid); if (err) return err; - if (peersid == SECSID_NULL) { - req->secid = sksec->sid; - req->peer_secid = SECSID_NULL; - } else { - err = security_sid_mls_copy(sksec->sid, peersid, &newsid); - if (err) - return err; - req->secid = newsid; - req->peer_secid = peersid; - } + err = selinux_conn_sid(sksec->sid, peersid, &connsid); + if (err) + return err; + req->secid = connsid; + req->peer_secid = peersid; return selinux_netlbl_inet_conn_request(req, family); } @@ -4363,6 +4555,11 @@ static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); } +static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk) +{ + skb_set_owner_w(skb, sk); +} + static int selinux_secmark_relabel_packet(u32 sid) { const struct task_security_struct *__tsec; @@ -4475,7 +4672,7 @@ static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) struct nlmsghdr *nlh; struct sk_security_struct *sksec = sk->sk_security; - if (skb->len < NLMSG_SPACE(0)) { + if (skb->len < NLMSG_HDRLEN) { err = -EINVAL; goto out; } @@ -4522,7 +4719,7 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, secmark_active = selinux_secmark_enabled(); netlbl_active = netlbl_enabled(); - peerlbl_active = netlbl_active || selinux_xfrm_enabled(); + peerlbl_active = selinux_peerlbl_enabled(); if (!secmark_active && !peerlbl_active) return NF_ACCEPT; @@ -4561,7 +4758,7 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, return NF_ACCEPT; } -static unsigned int selinux_ipv4_forward(unsigned int hooknum, +static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, @@ -4571,7 +4768,7 @@ static unsigned int selinux_ipv4_forward(unsigned int hooknum, } #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) -static unsigned int selinux_ipv6_forward(unsigned int hooknum, +static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, @@ -4584,6 +4781,7 @@ static unsigned int selinux_ipv6_forward(unsigned int hooknum, static unsigned int selinux_ip_output(struct sk_buff *skb, u16 family) { + struct sock *sk; u32 sid; if (!netlbl_enabled()) @@ -4592,8 +4790,27 @@ static unsigned int selinux_ip_output(struct sk_buff *skb, /* we do this in the LOCAL_OUT path and not the POST_ROUTING path * because we want to make sure we apply the necessary labeling * before IPsec is applied so we can leverage AH protection */ - if (skb->sk) { - struct sk_security_struct *sksec = skb->sk->sk_security; + sk = skb->sk; + if (sk) { + struct sk_security_struct *sksec; + + if (sk->sk_state == TCP_LISTEN) + /* if the socket is the listening state then this + * packet is a SYN-ACK packet which means it needs to + * be labeled based on the connection/request_sock and + * not the parent socket. unfortunately, we can't + * lookup the request_sock yet as it isn't queued on + * the parent socket until after the SYN-ACK is sent. + * the "solution" is to simply pass the packet as-is + * as any IP option based labeling should be copied + * from the initial connection request (in the IP + * layer). it is far from ideal, but until we get a + * security label in the packet itself this is the + * best we can do. */ + return NF_ACCEPT; + + /* standard practice, label using the parent socket */ + sksec = sk->sk_security; sid = sksec->sid; } else sid = SECINITSID_KERNEL; @@ -4603,7 +4820,7 @@ static unsigned int selinux_ip_output(struct sk_buff *skb, return NF_ACCEPT; } -static unsigned int selinux_ipv4_output(unsigned int hooknum, +static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, @@ -4663,27 +4880,36 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, * as fast and as clean as possible. */ if (!selinux_policycap_netpeer) return selinux_ip_postroute_compat(skb, ifindex, family); + + secmark_active = selinux_secmark_enabled(); + peerlbl_active = selinux_peerlbl_enabled(); + if (!secmark_active && !peerlbl_active) + return NF_ACCEPT; + + sk = skb->sk; + #ifdef CONFIG_XFRM /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec * packet transformation so allow the packet to pass without any checks * since we'll have another chance to perform access control checks * when the packet is on it's final way out. * NOTE: there appear to be some IPv6 multicast cases where skb->dst - * is NULL, in this case go ahead and apply access control. */ - if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) + * is NULL, in this case go ahead and apply access control. + * NOTE: if this is a local socket (skb->sk != NULL) that is in the + * TCP listening state we cannot wait until the XFRM processing + * is done as we will miss out on the SA label if we do; + * unfortunately, this means more work, but it is only once per + * connection. */ + if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && + !(sk != NULL && sk->sk_state == TCP_LISTEN)) return NF_ACCEPT; #endif - secmark_active = selinux_secmark_enabled(); - peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); - if (!secmark_active && !peerlbl_active) - return NF_ACCEPT; - /* if the packet is being forwarded then get the peer label from the - * packet itself; otherwise check to see if it is from a local - * application or the kernel, if from an application get the peer label - * from the sending socket, otherwise use the kernel's sid */ - sk = skb->sk; if (sk == NULL) { + /* Without an associated socket the packet is either coming + * from the kernel or it is being forwarded; check the packet + * to determine which and if the packet is being forwarded + * query the packet directly to determine the security label. */ if (skb->skb_iif) { secmark_perm = PACKET__FORWARD_OUT; if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) @@ -4692,7 +4918,45 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, secmark_perm = PACKET__SEND; peer_sid = SECINITSID_KERNEL; } + } else if (sk->sk_state == TCP_LISTEN) { + /* Locally generated packet but the associated socket is in the + * listening state which means this is a SYN-ACK packet. In + * this particular case the correct security label is assigned + * to the connection/request_sock but unfortunately we can't + * query the request_sock as it isn't queued on the parent + * socket until after the SYN-ACK packet is sent; the only + * viable choice is to regenerate the label like we do in + * selinux_inet_conn_request(). See also selinux_ip_output() + * for similar problems. */ + u32 skb_sid; + struct sk_security_struct *sksec = sk->sk_security; + if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) + return NF_DROP; + /* At this point, if the returned skb peerlbl is SECSID_NULL + * and the packet has been through at least one XFRM + * transformation then we must be dealing with the "final" + * form of labeled IPsec packet; since we've already applied + * all of our access controls on this packet we can safely + * pass the packet. */ + if (skb_sid == SECSID_NULL) { + switch (family) { + case PF_INET: + if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) + return NF_ACCEPT; + break; + case PF_INET6: + if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) + return NF_ACCEPT; + default: + return NF_DROP_ERR(-ECONNREFUSED); + } + } + if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) + return NF_DROP; + secmark_perm = PACKET__SEND; } else { + /* Locally generated packet, fetch the security label from the + * associated socket. */ struct sk_security_struct *sksec = sk->sk_security; peer_sid = sksec->sid; secmark_perm = PACKET__SEND; @@ -4730,7 +4994,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, return NF_ACCEPT; } -static unsigned int selinux_ipv4_postroute(unsigned int hooknum, +static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, @@ -4740,7 +5004,7 @@ static unsigned int selinux_ipv4_postroute(unsigned int hooknum, } #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) -static unsigned int selinux_ipv6_postroute(unsigned int hooknum, +static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, @@ -5286,7 +5550,7 @@ static int selinux_setprocattr(struct task_struct *p, str[size-1] = 0; size--; } - error = security_context_to_sid(value, size, &sid); + error = security_context_to_sid(value, size, &sid, GFP_KERNEL); if (error == -EINVAL && !strcmp(name, "fscreate")) { if (!capable(CAP_MAC_ADMIN)) { struct audit_buffer *ab; @@ -5356,11 +5620,11 @@ static int selinux_setprocattr(struct task_struct *p, /* Check for ptracing, and update the task SID if ok. Otherwise, leave SID unchanged and fail. */ ptsid = 0; - task_lock(p); + rcu_read_lock(); tracer = ptrace_parent(p); if (tracer) ptsid = task_sid(tracer); - task_unlock(p); + rcu_read_unlock(); if (tracer) { error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, @@ -5383,6 +5647,11 @@ abort_change: return error; } +static int selinux_ismaclabel(const char *name) +{ + return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); +} + static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return security_sid_to_context(secid, secdata, seclen); @@ -5390,7 +5659,7 @@ static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) { - return security_context_to_sid(secdata, seclen, secid); + return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); } static void selinux_release_secctx(char *secdata, u32 seclen) @@ -5456,7 +5725,7 @@ static void selinux_key_free(struct key *k) static int selinux_key_permission(key_ref_t key_ref, const struct cred *cred, - key_perm_t perm) + unsigned perm) { struct key *key; struct key_security_struct *ksec; @@ -5525,6 +5794,7 @@ static struct security_operations selinux_ops = { .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, .sb_parse_opts_str = selinux_parse_opts_str, + .dentry_init_security = selinux_dentry_init_security, .inode_alloc_security = selinux_inode_alloc_security, .inode_free_security = selinux_inode_free_security, @@ -5620,6 +5890,7 @@ static struct security_operations selinux_ops = { .getprocattr = selinux_getprocattr, .setprocattr = selinux_setprocattr, + .ismaclabel = selinux_ismaclabel, .secid_to_secctx = selinux_secid_to_secctx, .secctx_to_secid = selinux_secctx_to_secid, .release_secctx = selinux_release_secctx, @@ -5664,13 +5935,15 @@ static struct security_operations selinux_ops = { .tun_dev_attach_queue = selinux_tun_dev_attach_queue, .tun_dev_attach = selinux_tun_dev_attach, .tun_dev_open = selinux_tun_dev_open, + .skb_owned_by = selinux_skb_owned_by, #ifdef CONFIG_SECURITY_NETWORK_XFRM .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, .xfrm_policy_clone_security = selinux_xfrm_policy_clone, .xfrm_policy_free_security = selinux_xfrm_policy_free, .xfrm_policy_delete_security = selinux_xfrm_policy_delete, - .xfrm_state_alloc_security = selinux_xfrm_state_alloc, + .xfrm_state_alloc = selinux_xfrm_state_alloc, + .xfrm_state_alloc_acquire = selinux_xfrm_state_alloc_acquire, .xfrm_state_free_security = selinux_xfrm_state_free, .xfrm_state_delete_security = selinux_xfrm_state_delete, .xfrm_policy_lookup = selinux_xfrm_policy_lookup, |
