diff options
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 2 | ||||
| -rw-r--r-- | include/linux/capability.h | 36 | ||||
| -rw-r--r-- | include/linux/cred.h | 4 | ||||
| -rw-r--r-- | include/linux/security.h | 28 | ||||
| -rw-r--r-- | kernel/capability.c | 42 | ||||
| -rw-r--r-- | kernel/cred.c | 6 | ||||
| -rw-r--r-- | security/apparmor/lsm.c | 5 | ||||
| -rw-r--r-- | security/commoncap.c | 38 | ||||
| -rw-r--r-- | security/security.c | 16 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 13 |
10 files changed, 144 insertions, 46 deletions
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index c85438a..a8a277a 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -369,7 +369,7 @@ pci_read_config(struct file *filp, struct kobject *kobj, u8 *data = (u8*) buf; /* Several chips lock up trying to read undefined config space */ - if (security_capable(filp->f_cred, CAP_SYS_ADMIN) == 0) { + if (security_capable(&init_user_ns, filp->f_cred, CAP_SYS_ADMIN) == 0) { size = dev->cfg_size; } else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) { size = 128; diff --git a/include/linux/capability.h b/include/linux/capability.h index fb16a36..7c9c829 100644 --- a/include/linux/capability.h +++ b/include/linux/capability.h @@ -368,6 +368,17 @@ struct cpu_vfs_cap_data { #ifdef __KERNEL__ +struct dentry; +struct user_namespace; + +extern struct user_namespace init_user_ns; + +struct user_namespace *current_user_ns(void); + +extern const kernel_cap_t __cap_empty_set; +extern const kernel_cap_t __cap_full_set; +extern const kernel_cap_t __cap_init_eff_set; + /* * Internal kernel functions only */ @@ -530,10 +541,6 @@ static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a, cap_intersect(permitted, __cap_nfsd_set)); } -extern const kernel_cap_t __cap_empty_set; -extern const kernel_cap_t __cap_full_set; -extern const kernel_cap_t __cap_init_eff_set; - /** * has_capability - Determine if a task has a superior capability available * @t: The task in question @@ -544,7 +551,7 @@ extern const kernel_cap_t __cap_init_eff_set; * * Note that this does not set PF_SUPERPRIV on the task. */ -#define has_capability(t, cap) (security_real_capable((t), (cap)) == 0) +#define has_capability(t, cap) (security_real_capable((t), &init_user_ns, (cap)) == 0) /** * has_capability_noaudit - Determine if a task has a superior capability available (unaudited) @@ -558,12 +565,25 @@ extern const kernel_cap_t __cap_init_eff_set; * Note that this does not set PF_SUPERPRIV on the task. */ #define has_capability_noaudit(t, cap) \ - (security_real_capable_noaudit((t), (cap)) == 0) + (security_real_capable_noaudit((t), &init_user_ns, (cap)) == 0) -extern int capable(int cap); +extern bool capable(int cap); +extern bool ns_capable(struct user_namespace *ns, int cap); +extern bool task_ns_capable(struct task_struct *t, int cap); + +/** + * nsown_capable - Check superior capability to one's own user_ns + * @cap: The capability in question + * + * Return true if the current task has the given superior capability + * targeted at its own user namespace. + */ +static inline bool nsown_capable(int cap) +{ + return ns_capable(current_user_ns(), cap); +} /* audit system wants to get cap info from files as well */ -struct dentry; extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps); #endif /* __KERNEL__ */ diff --git a/include/linux/cred.h b/include/linux/cred.h index 4aaeab3..9aeeb0b 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -354,9 +354,11 @@ static inline void put_cred(const struct cred *_cred) #define current_fsgid() (current_cred_xxx(fsgid)) #define current_cap() (current_cred_xxx(cap_effective)) #define current_user() (current_cred_xxx(user)) -#define current_user_ns() (current_cred_xxx(user)->user_ns) +#define _current_user_ns() (current_cred_xxx(user)->user_ns) #define current_security() (current_cred_xxx(security)) +extern struct user_namespace *current_user_ns(void); + #define current_uid_gid(_uid, _gid) \ do { \ const struct cred *__cred; \ diff --git a/include/linux/security.h b/include/linux/security.h index 56cac52..ca02f17 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -47,13 +47,14 @@ struct ctl_table; struct audit_krule; +struct user_namespace; /* * These functions are in security/capability.c and are used * as the default capabilities functions */ extern int cap_capable(struct task_struct *tsk, const struct cred *cred, - int cap, int audit); + struct user_namespace *ns, int cap, int audit); extern int cap_settime(const struct timespec *ts, const struct timezone *tz); extern int cap_ptrace_access_check(struct task_struct *child, unsigned int mode); extern int cap_ptrace_traceme(struct task_struct *parent); @@ -1262,6 +1263,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * credentials. * @tsk contains the task_struct for the process. * @cred contains the credentials to use. + * @ns contains the user namespace we want the capability in * @cap contains the capability <include/linux/capability.h>. * @audit: Whether to write an audit message or not * Return 0 if the capability is granted for @tsk. @@ -1384,7 +1386,7 @@ struct security_operations { const kernel_cap_t *inheritable, const kernel_cap_t *permitted); int (*capable) (struct task_struct *tsk, const struct cred *cred, - int cap, int audit); + struct user_namespace *ns, int cap, int audit); int (*quotactl) (int cmds, int type, int id, struct super_block *sb); int (*quota_on) (struct dentry *dentry); int (*syslog) (int type); @@ -1665,9 +1667,12 @@ int security_capset(struct cred *new, const struct cred *old, const kernel_cap_t *effective, const kernel_cap_t *inheritable, const kernel_cap_t *permitted); -int security_capable(const struct cred *cred, int cap); -int security_real_capable(struct task_struct *tsk, int cap); -int security_real_capable_noaudit(struct task_struct *tsk, int cap); +int security_capable(struct user_namespace *ns, const struct cred *cred, + int cap); +int security_real_capable(struct task_struct *tsk, struct user_namespace *ns, + int cap); +int security_real_capable_noaudit(struct task_struct *tsk, + struct user_namespace *ns, int cap); int security_quotactl(int cmds, int type, int id, struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); @@ -1860,28 +1865,29 @@ static inline int security_capset(struct cred *new, return cap_capset(new, old, effective, inheritable, permitted); } -static inline int security_capable(const struct cred *cred, int cap) +static inline int security_capable(struct user_namespace *ns, + const struct cred *cred, int cap) { - return cap_capable(current, cred, cap, SECURITY_CAP_AUDIT); + return cap_capable(current, cred, ns, cap, SECURITY_CAP_AUDIT); } -static inline int security_real_capable(struct task_struct *tsk, int cap) +static inline int security_real_capable(struct task_struct *tsk, struct user_namespace *ns, int cap) { int ret; rcu_read_lock(); - ret = cap_capable(tsk, __task_cred(tsk), cap, SECURITY_CAP_AUDIT); + ret = cap_capable(tsk, __task_cred(tsk), ns, cap, SECURITY_CAP_AUDIT); rcu_read_unlock(); return ret; } static inline -int security_real_capable_noaudit(struct task_struct *tsk, int cap) +int security_real_capable_noaudit(struct task_struct *tsk, struct user_namespace *ns, int cap) { int ret; rcu_read_lock(); - ret = cap_capable(tsk, __task_cred(tsk), cap, + ret = cap_capable(tsk, __task_cred(tsk), ns, cap, SECURITY_CAP_NOAUDIT); rcu_read_unlock(); return ret; diff --git a/kernel/capability.c b/kernel/capability.c index 9e9385f..0a3d2c8 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -14,6 +14,7 @@ #include <linux/security.h> #include <linux/syscalls.h> #include <linux/pid_namespace.h> +#include <linux/user_namespace.h> #include <asm/uaccess.h> /* @@ -299,17 +300,48 @@ error: * This sets PF_SUPERPRIV on the task if the capability is available on the * assumption that it's about to be used. */ -int capable(int cap) +bool capable(int cap) +{ + return ns_capable(&init_user_ns, cap); +} +EXPORT_SYMBOL(capable); + +/** + * ns_capable - Determine if the current task has a superior capability in effect + * @ns: The usernamespace we want the capability in + * @cap: The capability to be tested for + * + * Return true if the current task has the given superior capability currently + * available for use, false if not. + * + * This sets PF_SUPERPRIV on the task if the capability is available on the + * assumption that it's about to be used. + */ +bool ns_capable(struct user_namespace *ns, int cap) { if (unlikely(!cap_valid(cap))) { printk(KERN_CRIT "capable() called with invalid cap=%u\n", cap); BUG(); } - if (security_capable(current_cred(), cap) == 0) { + if (security_capable(ns, current_cred(), cap) == 0) { current->flags |= PF_SUPERPRIV; - return 1; + return true; } - return 0; + return false; } -EXPORT_SYMBOL(capable); +EXPORT_SYMBOL(ns_capable); + +/** + * task_ns_capable - Determine whether current task has a superior + * capability targeted at a specific task's user namespace. + * @t: The task whose user namespace is targeted. + * @cap: The capability in question. + * + * Return true if it does, false otherwise. + */ +bool task_ns_capable(struct task_struct *t, int cap) +{ + return ns_capable(task_cred_xxx(t, user)->user_ns, cap); +} +EXPORT_SYMBOL(task_ns_capable); diff --git a/kernel/cred.c b/kernel/cred.c index 2343c132..5557b55 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -741,6 +741,12 @@ int set_create_files_as(struct cred *new, struct inode *inode) } EXPORT_SYMBOL(set_create_files_as); +struct user_namespace *current_user_ns(void) +{ + return _current_user_ns(); +} +EXPORT_SYMBOL(current_user_ns); + #ifdef CONFIG_DEBUG_CREDENTIALS bool creds_are_invalid(const struct cred *cred) diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index d21a427..ae3a698 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -22,6 +22,7 @@ #include <linux/ctype.h> #include <linux/sysctl.h> #include <linux/audit.h> +#include <linux/user_namespace.h> #include <net/sock.h> #include "include/apparmor.h" @@ -136,11 +137,11 @@ static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective, } static int apparmor_capable(struct task_struct *task, const struct cred *cred, - int cap, int audit) + struct user_namespace *ns, int cap, int audit) { struct aa_profile *profile; /* cap_capable returns 0 on success, else -EPERM */ - int error = cap_capable(task, cred, cap, audit); + int error = cap_capable(task, cred, ns, cap, audit); if (!error) { profile = aa_cred_profile(cred); if (!unconfined(profile)) diff --git a/security/commoncap.c b/security/commoncap.c index 49c57fd..43a205b 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -27,6 +27,7 @@ #include <linux/sched.h> #include <linux/prctl.h> #include <linux/securebits.h> +#include <linux/user_namespace.h> /* * If a non-root user executes a setuid-root binary in @@ -67,6 +68,7 @@ EXPORT_SYMBOL(cap_netlink_recv); * cap_capable - Determine whether a task has a particular effective capability * @tsk: The task to query * @cred: The credentials to use + * @ns: The user namespace in which we need the capability * @cap: The capability to check for * @audit: Whether to write an audit message or not * @@ -78,10 +80,30 @@ EXPORT_SYMBOL(cap_netlink_recv); * cap_has_capability() returns 0 when a task has a capability, but the * kernel's capable() and has_capability() returns 1 for this case. */ -int cap_capable(struct task_struct *tsk, const struct cred *cred, int cap, - int audit) +int cap_capable(struct task_struct *tsk, const struct cred *cred, + struct user_namespace *targ_ns, int cap, int audit) { - return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; + for (;;) { + /* The creator of the user namespace has all caps. */ + if (targ_ns != &init_user_ns && targ_ns->creator == cred->user) + return 0; + + /* Do we have the necessary capabilities? */ + if (targ_ns == cred->user->user_ns) + return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; + + /* Have we tried all of the parent namespaces? */ + if (targ_ns == &init_user_ns) + return -EPERM; + + /* + *If you have a capability in a parent user ns, then you have + * it over all children user namespaces as well. + */ + targ_ns = targ_ns->creator->user_ns; + } + + /* We never get here */ } /** @@ -176,7 +198,8 @@ static inline int cap_inh_is_capped(void) /* they are so limited unless the current task has the CAP_SETPCAP * capability */ - if (cap_capable(current, current_cred(), CAP_SETPCAP, + if (cap_capable(current, current_cred(), + current_cred()->user->user_ns, CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0) return 0; return 1; @@ -828,7 +851,8 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, & (new->securebits ^ arg2)) /*[1]*/ || ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/ || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/ - || (cap_capable(current, current_cred(), CAP_SETPCAP, + || (cap_capable(current, current_cred(), + current_cred()->user->user_ns, CAP_SETPCAP, SECURITY_CAP_AUDIT) != 0) /*[4]*/ /* * [1] no changing of bits that are locked @@ -893,7 +917,7 @@ int cap_vm_enough_memory(struct mm_struct *mm, long pages) { int cap_sys_admin = 0; - if (cap_capable(current, current_cred(), CAP_SYS_ADMIN, + if (cap_capable(current, current_cred(), &init_user_ns, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT) == 0) cap_sys_admin = 1; return __vm_enough_memory(mm, pages, cap_sys_admin); @@ -920,7 +944,7 @@ int cap_file_mmap(struct file *file, unsigned long reqprot, int ret = 0; if (addr < dac_mmap_min_addr) { - ret = cap_capable(current, current_cred(), CAP_SYS_RAWIO, + ret = cap_capable(current, current_cred(), &init_user_ns, CAP_SYS_RAWIO, SECURITY_CAP_AUDIT); /* set PF_SUPERPRIV if it turns out we allow the low mmap */ if (ret == 0) diff --git a/security/security.c b/security/security.c index 9187665..1011423 100644 --- a/security/security.c +++ b/security/security.c @@ -154,29 +154,33 @@ int security_capset(struct cred *new, const struct cred *old, effective, inheritable, permitted); } -int security_capable(const struct cred *cred, int cap) +int security_capable(struct user_namespace *ns, const struct cred *cred, + int cap) { - return security_ops->capable(current, cred, cap, SECURITY_CAP_AUDIT); + return security_ops->capable(current, cred, ns, cap, + SECURITY_CAP_AUDIT); } -int security_real_capable(struct task_struct *tsk, int cap) +int security_real_capable(struct task_struct *tsk, struct user_namespace *ns, + int cap) { const struct cred *cred; int ret; cred = get_task_cred(tsk); - ret = security_ops->capable(tsk, cred, cap, SECURITY_CAP_AUDIT); + ret = security_ops->capable(tsk, cred, ns, cap, SECURITY_CAP_AUDIT); put_cred(cred); return ret; } -int security_real_capable_noaudit(struct task_struct *tsk, int cap) +int security_real_capable_noaudit(struct task_struct *tsk, + struct user_namespace *ns, int cap) { const struct cred *cred; int ret; cred = get_task_cred(tsk); - ret = security_ops->capable(tsk, cred, cap, SECURITY_CAP_NOAUDIT); + ret = security_ops->capable(tsk, cred, ns, cap, SECURITY_CAP_NOAUDIT); put_cred(cred); return ret; } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 6475e1f..c67f863 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -79,6 +79,7 @@ #include <linux/mutex.h> #include <linux/posix-timers.h> #include <linux/syslog.h> +#include <linux/user_namespace.h> #include "avc.h" #include "objsec.h" @@ -1846,11 +1847,11 @@ static int selinux_capset(struct cred *new, const struct cred *old, */ static int selinux_capable(struct task_struct *tsk, const struct cred *cred, - int cap, int audit) + struct user_namespace *ns, int cap, int audit) { int rc; - rc = cap_capable(tsk, cred, cap, audit); + rc = cap_capable(tsk, cred, ns, cap, audit); if (rc) return rc; @@ -1931,7 +1932,8 @@ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) { int rc, cap_sys_admin = 0; - rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN, + rc = selinux_capable(current, current_cred(), + &init_user_ns, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT); if (rc == 0) cap_sys_admin = 1; @@ -2834,7 +2836,8 @@ static int selinux_inode_getsecurity(const struct inode *inode, const char *name * and lack of permission just means that we fall back to the * in-core context value, not a denial. */ - error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN, + error = selinux_capable(current, current_cred(), + &init_user_ns, CAP_MAC_ADMIN, SECURITY_CAP_NOAUDIT); if (!error) error = security_sid_to_context_force(isec->sid, &context, @@ -2968,7 +2971,7 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd, case KDSKBENT: case KDSKBSENT: error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG, - SECURITY_CAP_AUDIT); + SECURITY_CAP_AUDIT); break; /* default case assumes that the command will go |
