diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 235 |
1 files changed, 187 insertions, 48 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 61a53367d029..c956390a9136 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -51,6 +51,7 @@ #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/net_namespace.h> #include <net/netlabel.h> @@ -60,7 +61,7 @@ #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> @@ -80,6 +81,7 @@ #include <linux/syslog.h> #include <linux/user_namespace.h> #include <linux/export.h> +#include <linux/security.h> #include <linux/msg.h> #include <linux/shm.h> @@ -283,13 +285,14 @@ 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); @@ -551,7 +554,9 @@ 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 +584,12 @@ 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 @@ -669,14 +680,21 @@ 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((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; + } } - /* 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 +709,11 @@ 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 +745,8 @@ 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 +774,37 @@ 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 +819,14 @@ 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 +859,7 @@ 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 +1003,7 @@ 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); @@ -1190,6 +1245,8 @@ 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; @@ -1515,6 +1572,18 @@ static inline int path_has_perm(const struct cred *cred, return inode_has_perm(cred, inode, av, &ad, 0); } +/* 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, 0); +} + /* Check whether a task can use an open file descriptor to access an inode in a given way. Check access to the descriptor itself, and then use dentry_has_perm to @@ -1528,7 +1597,7 @@ static int file_has_perm(const struct cred *cred, u32 av) { struct file_security_struct *fsec = file->f_security; - struct inode *inode = file->f_path.dentry->d_inode; + struct inode *inode = file_inode(file); struct common_audit_data ad; u32 sid = cred_sid(cred); int rc; @@ -1957,7 +2026,7 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm) struct task_security_struct *new_tsec; struct inode_security_struct *isec; struct common_audit_data ad; - struct inode *inode = bprm->file->f_path.dentry->d_inode; + struct inode *inode = file_inode(bprm->file); int rc; rc = cap_bprm_set_creds(bprm); @@ -2109,14 +2178,14 @@ 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); @@ -2483,6 +2552,40 @@ 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, void **value, size_t *len) @@ -2817,7 +2920,10 @@ 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; } @@ -2905,6 +3011,7 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name, if (rc) return rc; + isec->sclass = inode_mode_to_security_class(inode->i_mode); isec->sid = newsid; isec->initialized = 1; return 0; @@ -2929,7 +3036,7 @@ static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) static int selinux_revalidate_file_permission(struct file *file, int mask) { const struct cred *cred = current_cred(); - struct inode *inode = file->f_path.dentry->d_inode; + struct inode *inode = file_inode(file); /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) @@ -2941,7 +3048,7 @@ static int selinux_revalidate_file_permission(struct file *file, int mask) static int selinux_file_permission(struct file *file, int mask) { - struct inode *inode = file->f_path.dentry->d_inode; + struct inode *inode = file_inode(file); struct file_security_struct *fsec = file->f_security; struct inode_security_struct *isec = inode->i_security; u32 sid = current_sid(); @@ -3135,11 +3242,6 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, switch (cmd) { case F_SETFL: - if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { - err = -EINVAL; - break; - } - if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { err = file_has_perm(cred, file, FILE__WRITE); break; @@ -3162,10 +3264,6 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, case F_SETLK64: case F_SETLKW64: #endif - if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { - err = -EINVAL; - break; - } err = file_has_perm(cred, file, FILE__LOCK); break; } @@ -3218,7 +3316,7 @@ static int selinux_file_open(struct file *file, const struct cred *cred) struct inode_security_struct *isec; fsec = file->f_security; - isec = file->f_path.dentry->d_inode->i_security; + isec = file_inode(file)->i_security; /* * Save inode label and policy sequence number * at open-time so that selinux_file_permission @@ -3236,7 +3334,7 @@ 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 */ @@ -4372,6 +4470,11 @@ 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; @@ -4399,6 +4502,24 @@ static void selinux_req_classify_flow(const struct request_sock *req, fl->flowi_secid = req->secid; } +static int selinux_tun_dev_alloc_security(void **security) +{ + struct tun_security_struct *tunsec; + + tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); + if (!tunsec) + return -ENOMEM; + tunsec->sid = current_sid(); + + *security = tunsec; + return 0; +} + +static void selinux_tun_dev_free_security(void *security) +{ + kfree(security); +} + static int selinux_tun_dev_create(void) { u32 sid = current_sid(); @@ -4414,8 +4535,17 @@ static int selinux_tun_dev_create(void) NULL); } -static void selinux_tun_dev_post_create(struct sock *sk) +static int selinux_tun_dev_attach_queue(void *security) +{ + struct tun_security_struct *tunsec = security; + + return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, + TUN_SOCKET__ATTACH_QUEUE, NULL); +} + +static int selinux_tun_dev_attach(struct sock *sk, void *security) { + struct tun_security_struct *tunsec = security; struct sk_security_struct *sksec = sk->sk_security; /* we don't currently perform any NetLabel based labeling here and it @@ -4425,20 +4555,19 @@ static void selinux_tun_dev_post_create(struct sock *sk) * cause confusion to the TUN user that had no idea network labeling * protocols were being used */ - /* see the comments in selinux_tun_dev_create() about why we don't use - * the sockcreate SID here */ - - sksec->sid = current_sid(); + sksec->sid = tunsec->sid; sksec->sclass = SECCLASS_TUN_SOCKET; + + return 0; } -static int selinux_tun_dev_attach(struct sock *sk) +static int selinux_tun_dev_open(void *security) { - struct sk_security_struct *sksec = sk->sk_security; + struct tun_security_struct *tunsec = security; u32 sid = current_sid(); int err; - err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, + err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__RELABELFROM, NULL); if (err) return err; @@ -4446,8 +4575,7 @@ static int selinux_tun_dev_attach(struct sock *sk) TUN_SOCKET__RELABELTO, NULL); if (err) return err; - - sksec->sid = sid; + tunsec->sid = sid; return 0; } @@ -4459,7 +4587,7 @@ 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; } @@ -5367,6 +5495,11 @@ 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); @@ -5509,6 +5642,7 @@ 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, @@ -5604,6 +5738,7 @@ 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, @@ -5642,9 +5777,13 @@ static struct security_operations selinux_ops = { .secmark_refcount_inc = selinux_secmark_refcount_inc, .secmark_refcount_dec = selinux_secmark_refcount_dec, .req_classify_flow = selinux_req_classify_flow, + .tun_dev_alloc_security = selinux_tun_dev_alloc_security, + .tun_dev_free_security = selinux_tun_dev_free_security, .tun_dev_create = selinux_tun_dev_create, - .tun_dev_post_create = selinux_tun_dev_post_create, + .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, |