diff options
Diffstat (limited to 'security')
| -rw-r--r-- | security/commoncap.c | 59 | ||||
| -rw-r--r-- | security/dummy.c | 16 |
2 files changed, 61 insertions, 14 deletions
diff --git a/security/commoncap.c b/security/commoncap.c index 778cb0cfc5d8..48ca5b092768 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -24,6 +24,25 @@ #include <linux/hugetlb.h> #include <linux/mount.h> +#ifdef CONFIG_SECURITY_FILE_CAPABILITIES +/* + * Because of the reduced scope of CAP_SETPCAP when filesystem + * capabilities are in effect, it is safe to allow this capability to + * be available in the default configuration. + */ +# define CAP_INIT_BSET CAP_FULL_SET +#else /* ie. ndef CONFIG_SECURITY_FILE_CAPABILITIES */ +# define CAP_INIT_BSET CAP_INIT_EFF_SET +#endif /* def CONFIG_SECURITY_FILE_CAPABILITIES */ + +kernel_cap_t cap_bset = CAP_INIT_BSET; /* systemwide capability bound */ +EXPORT_SYMBOL(cap_bset); + +/* Global security state */ + +unsigned securebits = SECUREBITS_DEFAULT; /* systemwide security settings */ +EXPORT_SYMBOL(securebits); + int cap_netlink_send(struct sock *sk, struct sk_buff *skb) { NETLINK_CB(skb).eff_cap = current->cap_effective; @@ -73,14 +92,44 @@ int cap_capget (struct task_struct *target, kernel_cap_t *effective, return 0; } +#ifdef CONFIG_SECURITY_FILE_CAPABILITIES + +static inline int cap_block_setpcap(struct task_struct *target) +{ + /* + * No support for remote process capability manipulation with + * filesystem capability support. + */ + return (target != current); +} + +static inline int cap_inh_is_capped(void) +{ + /* + * return 1 if changes to the inheritable set are limited + * to the old permitted set. + */ + return !cap_capable(current, CAP_SETPCAP); +} + +#else /* ie., ndef CONFIG_SECURITY_FILE_CAPABILITIES */ + +static inline int cap_block_setpcap(struct task_struct *t) { return 0; } +static inline int cap_inh_is_capped(void) { return 1; } + +#endif /* def CONFIG_SECURITY_FILE_CAPABILITIES */ + int cap_capset_check (struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted) { - /* Derived from kernel/capability.c:sys_capset. */ - /* verify restrictions on target's new Inheritable set */ - if (!cap_issubset (*inheritable, - cap_combine (target->cap_inheritable, - current->cap_permitted))) { + if (cap_block_setpcap(target)) { + return -EPERM; + } + if (cap_inh_is_capped() + && !cap_issubset(*inheritable, + cap_combine(target->cap_inheritable, + current->cap_permitted))) { + /* incapable of using this inheritable set */ return -EPERM; } diff --git a/security/dummy.c b/security/dummy.c index bc43d4c7383e..6d895ade73de 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -37,15 +37,13 @@ static int dummy_capget (struct task_struct *target, kernel_cap_t * effective, kernel_cap_t * inheritable, kernel_cap_t * permitted) { *effective = *inheritable = *permitted = 0; - if (!issecure(SECURE_NOROOT)) { - if (target->euid == 0) { - *permitted |= (~0 & ~CAP_FS_MASK); - *effective |= (~0 & ~CAP_TO_MASK(CAP_SETPCAP) & ~CAP_FS_MASK); - } - if (target->fsuid == 0) { - *permitted |= CAP_FS_MASK; - *effective |= CAP_FS_MASK; - } + if (target->euid == 0) { + *permitted |= (~0 & ~CAP_FS_MASK); + *effective |= (~0 & ~CAP_TO_MASK(CAP_SETPCAP) & ~CAP_FS_MASK); + } + if (target->fsuid == 0) { + *permitted |= CAP_FS_MASK; + *effective |= CAP_FS_MASK; } return 0; } |