aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--fs/open.c12
-rw-r--r--include/linux/security.h48
-rw-r--r--kernel/capability.c227
-rw-r--r--security/commoncap.c29
-rw-r--r--security/security.c18
-rw-r--r--security/selinux/hooks.c10
6 files changed, 61 insertions, 283 deletions
diff --git a/fs/open.c b/fs/open.c
index 83cdb9d..500cc0c 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -441,17 +441,7 @@ asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
current->fsgid = current->gid;
if (!issecure(SECURE_NO_SETUID_FIXUP)) {
- /*
- * Clear the capabilities if we switch to a non-root user
- */
-#ifndef CONFIG_SECURITY_FILE_CAPABILITIES
- /*
- * FIXME: There is a race here against sys_capset. The
- * capabilities can change yet we will restore the old
- * value below. We should hold task_capabilities_lock,
- * but we cannot because user_path_at can sleep.
- */
-#endif /* ndef CONFIG_SECURITY_FILE_CAPABILITIES */
+ /* Clear the capabilities if we switch to a non-root user */
if (current->uid)
old_cap = cap_set_effective(__cap_empty_set);
else
diff --git a/include/linux/security.h b/include/linux/security.h
index 5fe28a6..d1ce8be 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -53,8 +53,8 @@ extern int cap_settime(struct timespec *ts, struct timezone *tz);
extern int cap_ptrace_may_access(struct task_struct *child, unsigned int mode);
extern int cap_ptrace_traceme(struct task_struct *parent);
extern int cap_capget(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted);
-extern int cap_capset_check(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted);
-extern void cap_capset_set(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted);
+extern int cap_capset_check(kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted);
+extern void cap_capset_set(kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted);
extern int cap_bprm_set_security(struct linux_binprm *bprm);
extern void cap_bprm_apply_creds(struct linux_binprm *bprm, int unsafe);
extern int cap_bprm_secureexec(struct linux_binprm *bprm);
@@ -1191,24 +1191,14 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* Return 0 if the capability sets were successfully obtained.
* @capset_check:
* Check permission before setting the @effective, @inheritable, and
- * @permitted capability sets for the @target process.
- * Caveat: @target is also set to current if a set of processes is
- * specified (i.e. all processes other than current and init or a
- * particular process group). Hence, the capset_set hook may need to
- * revalidate permission to the actual target process.
- * @target contains the task_struct structure for target process.
+ * @permitted capability sets for the current process.
* @effective contains the effective capability set.
* @inheritable contains the inheritable capability set.
* @permitted contains the permitted capability set.
* Return 0 if permission is granted.
* @capset_set:
* Set the @effective, @inheritable, and @permitted capability sets for
- * the @target process. Since capset_check cannot always check permission
- * to the real @target process, this hook may also perform permission
- * checking to determine if the current process is allowed to set the
- * capability sets of the @target process. However, this hook has no way
- * of returning an error due to the structure of the sys_capset code.
- * @target contains the task_struct structure for target process.
+ * the current process.
* @effective contains the effective capability set.
* @inheritable contains the inheritable capability set.
* @permitted contains the permitted capability set.
@@ -1303,12 +1293,10 @@ struct security_operations {
int (*capget) (struct task_struct *target,
kernel_cap_t *effective,
kernel_cap_t *inheritable, kernel_cap_t *permitted);
- int (*capset_check) (struct task_struct *target,
- kernel_cap_t *effective,
+ int (*capset_check) (kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted);
- void (*capset_set) (struct task_struct *target,
- kernel_cap_t *effective,
+ void (*capset_set) (kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted);
int (*capable) (struct task_struct *tsk, int cap, int audit);
@@ -1572,12 +1560,10 @@ int security_capget(struct task_struct *target,
kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted);
-int security_capset_check(struct task_struct *target,
- kernel_cap_t *effective,
+int security_capset_check(kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted);
-void security_capset_set(struct task_struct *target,
- kernel_cap_t *effective,
+void security_capset_set(kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted);
int security_capable(struct task_struct *tsk, int cap);
@@ -1769,20 +1755,18 @@ static inline int security_capget(struct task_struct *target,
return cap_capget(target, effective, inheritable, permitted);
}
-static inline int security_capset_check(struct task_struct *target,
- kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
+static inline int security_capset_check(kernel_cap_t *effective,
+ kernel_cap_t *inheritable,
+ kernel_cap_t *permitted)
{
- return cap_capset_check(target, effective, inheritable, permitted);
+ return cap_capset_check(effective, inheritable, permitted);
}
-static inline void security_capset_set(struct task_struct *target,
- kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
+static inline void security_capset_set(kernel_cap_t *effective,
+ kernel_cap_t *inheritable,
+ kernel_cap_t *permitted)
{
- cap_capset_set(target, effective, inheritable, permitted);
+ cap_capset_set(effective, inheritable, permitted);
}
static inline int security_capable(struct task_struct *tsk, int cap)
diff --git a/kernel/capability.c b/kernel/capability.c
index adb262f..58b0051 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -127,160 +127,6 @@ static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
return 0;
}
-#ifndef CONFIG_SECURITY_FILE_CAPABILITIES
-
-/*
- * Without filesystem capability support, we nominally support one process
- * setting the capabilities of another
- */
-static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
- kernel_cap_t *pIp, kernel_cap_t *pPp)
-{
- struct task_struct *target;
- int ret;
-
- spin_lock(&task_capability_lock);
- read_lock(&tasklist_lock);
-
- if (pid && pid != task_pid_vnr(current)) {
- target = find_task_by_vpid(pid);
- if (!target) {
- ret = -ESRCH;
- goto out;
- }
- } else
- target = current;
-
- ret = security_capget(target, pEp, pIp, pPp);
-
-out:
- read_unlock(&tasklist_lock);
- spin_unlock(&task_capability_lock);
-
- return ret;
-}
-
-/*
- * cap_set_pg - set capabilities for all processes in a given process
- * group. We call this holding task_capability_lock and tasklist_lock.
- */
-static inline int cap_set_pg(int pgrp_nr, kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
-{
- struct task_struct *g, *target;
- int ret = -EPERM;
- int found = 0;
- struct pid *pgrp;
-
- spin_lock(&task_capability_lock);
- read_lock(&tasklist_lock);
-
- pgrp = find_vpid(pgrp_nr);
- do_each_pid_task(pgrp, PIDTYPE_PGID, g) {
- target = g;
- while_each_thread(g, target) {
- if (!security_capset_check(target, effective,
- inheritable, permitted)) {
- security_capset_set(target, effective,
- inheritable, permitted);
- ret = 0;
- }
- found = 1;
- }
- } while_each_pid_task(pgrp, PIDTYPE_PGID, g);
-
- read_unlock(&tasklist_lock);
- spin_unlock(&task_capability_lock);
-
- if (!found)
- ret = 0;
- return ret;
-}
-
-/*
- * cap_set_all - set capabilities for all processes other than init
- * and self. We call this holding task_capability_lock and tasklist_lock.
- */
-static inline int cap_set_all(kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
-{
- struct task_struct *g, *target;
- int ret = -EPERM;
- int found = 0;
-
- spin_lock(&task_capability_lock);
- read_lock(&tasklist_lock);
-
- do_each_thread(g, target) {
- if (target == current
- || is_container_init(target->group_leader))
- continue;
- found = 1;
- if (security_capset_check(target, effective, inheritable,
- permitted))
- continue;
- ret = 0;
- security_capset_set(target, effective, inheritable, permitted);
- } while_each_thread(g, target);
-
- read_unlock(&tasklist_lock);
- spin_unlock(&task_capability_lock);
-
- if (!found)
- ret = 0;
-
- return ret;
-}
-
-/*
- * Given the target pid does not refer to the current process we
- * need more elaborate support... (This support is not present when
- * filesystem capabilities are configured.)
- */
-static inline int do_sys_capset_other_tasks(pid_t pid, kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
-{
- struct task_struct *target;
- int ret;
-
- if (!capable(CAP_SETPCAP))
- return -EPERM;
-
- if (pid == -1) /* all procs other than current and init */
- return cap_set_all(effective, inheritable, permitted);
-
- else if (pid < 0) /* all procs in process group */
- return cap_set_pg(-pid, effective, inheritable, permitted);
-
- /* target != current */
- spin_lock(&task_capability_lock);
- read_lock(&tasklist_lock);
-
- target = find_task_by_vpid(pid);
- if (!target)
- ret = -ESRCH;
- else {
- ret = security_capset_check(target, effective, inheritable,
- permitted);
-
- /* having verified that the proposed changes are legal,
- we now put them into effect. */
- if (!ret)
- security_capset_set(target, effective, inheritable,
- permitted);
- }
-
- read_unlock(&tasklist_lock);
- spin_unlock(&task_capability_lock);
-
- return ret;
-}
-
-#else /* ie., def CONFIG_SECURITY_FILE_CAPABILITIES */
-
/*
* If we have configured with filesystem capability support, then the
* only thing that can change the capabilities of the current process
@@ -315,22 +161,6 @@ static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
}
/*
- * With filesystem capability support configured, the kernel does not
- * permit the changing of capabilities in one process by another
- * process. (CAP_SETPCAP has much less broad semantics when configured
- * this way.)
- */
-static inline int do_sys_capset_other_tasks(pid_t pid,
- kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
-{
- return -EPERM;
-}
-
-#endif /* ie., ndef CONFIG_SECURITY_FILE_CAPABILITIES */
-
-/*
* Atomically modify the effective capabilities returning the original
* value. No permission check is performed here - it is assumed that the
* caller is permitted to set the desired effective capabilities.
@@ -424,16 +254,14 @@ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
* @data: pointer to struct that contains the effective, permitted,
* and inheritable capabilities
*
- * Set capabilities for a given process, all processes, or all
- * processes in a given process group.
+ * Set capabilities for the current process only. The ability to any other
+ * process(es) has been deprecated and removed.
*
* The restrictions on setting capabilities are specified as:
*
- * [pid is for the 'target' task. 'current' is the calling task.]
- *
- * I: any raised capabilities must be a subset of the (old current) permitted
- * P: any raised capabilities must be a subset of the (old current) permitted
- * E: must be set to a subset of (new target) permitted
+ * I: any raised capabilities must be a subset of the old permitted
+ * P: any raised capabilities must be a subset of the old permitted
+ * E: must be set to a subset of new permitted
*
* Returns 0 on success and < 0 on error.
*/
@@ -452,10 +280,13 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
if (get_user(pid, &header->pid))
return -EFAULT;
+ /* may only affect current now */
+ if (pid != 0 && pid != task_pid_vnr(current))
+ return -EPERM;
+
if (copy_from_user(&kdata, data, tocopy
- * sizeof(struct __user_cap_data_struct))) {
+ * sizeof(struct __user_cap_data_struct)))
return -EFAULT;
- }
for (i = 0; i < tocopy; i++) {
effective.cap[i] = kdata[i].effective;
@@ -473,32 +304,20 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
if (ret)
return ret;
- if (pid && (pid != task_pid_vnr(current)))
- ret = do_sys_capset_other_tasks(pid, &effective, &inheritable,
- &permitted);
- else {
- /*
- * This lock is required even when filesystem
- * capability support is configured - it protects the
- * sys_capget() call from returning incorrect data in
- * the case that the targeted process is not the
- * current one.
- */
- spin_lock(&task_capability_lock);
-
- ret = security_capset_check(current, &effective, &inheritable,
- &permitted);
- /*
- * Having verified that the proposed changes are
- * legal, we now put them into effect.
- */
- if (!ret)
- security_capset_set(current, &effective, &inheritable,
- &permitted);
- spin_unlock(&task_capability_lock);
- }
-
+ /* This lock is required even when filesystem capability support is
+ * configured - it protects the sys_capget() call from returning
+ * incorrect data in the case that the targeted process is not the
+ * current one.
+ */
+ spin_lock(&task_capability_lock);
+ ret = security_capset_check(&effective, &inheritable, &permitted);
+ /* Having verified that the proposed changes are legal, we now put them
+ * into effect.
+ */
+ if (!ret)
+ security_capset_set(&effective, &inheritable, &permitted);
+ spin_unlock(&task_capability_lock);
return ret;
}
diff --git a/security/commoncap.c b/security/commoncap.c
index 8283271..e3f36ef 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -96,15 +96,6 @@ int cap_capget (struct task_struct *target, kernel_cap_t *effective,
#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)
{
/*
@@ -119,7 +110,6 @@ static inline int cap_limit_ptraced_target(void) { return 1; }
#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; }
static inline int cap_limit_ptraced_target(void)
{
@@ -128,21 +118,18 @@ static inline int cap_limit_ptraced_target(void)
#endif /* def CONFIG_SECURITY_FILE_CAPABILITIES */
-int cap_capset_check (struct task_struct *target, kernel_cap_t *effective,
+int cap_capset_check (kernel_cap_t *effective,
kernel_cap_t *inheritable, kernel_cap_t *permitted)
{
- if (cap_block_setpcap(target)) {
- return -EPERM;
- }
if (cap_inh_is_capped()
&& !cap_issubset(*inheritable,
- cap_combine(target->cap_inheritable,
+ cap_combine(current->cap_inheritable,
current->cap_permitted))) {
/* incapable of using this inheritable set */
return -EPERM;
}
if (!cap_issubset(*inheritable,
- cap_combine(target->cap_inheritable,
+ cap_combine(current->cap_inheritable,
current->cap_bset))) {
/* no new pI capabilities outside bounding set */
return -EPERM;
@@ -150,7 +137,7 @@ int cap_capset_check (struct task_struct *target, kernel_cap_t *effective,
/* verify restrictions on target's new Permitted set */
if (!cap_issubset (*permitted,
- cap_combine (target->cap_permitted,
+ cap_combine (current->cap_permitted,
current->cap_permitted))) {
return -EPERM;
}
@@ -163,12 +150,12 @@ int cap_capset_check (struct task_struct *target, kernel_cap_t *effective,
return 0;
}
-void cap_capset_set (struct task_struct *target, kernel_cap_t *effective,
+void cap_capset_set (kernel_cap_t *effective,
kernel_cap_t *inheritable, kernel_cap_t *permitted)
{
- target->cap_effective = *effective;
- target->cap_inheritable = *inheritable;
- target->cap_permitted = *permitted;
+ current->cap_effective = *effective;
+ current->cap_inheritable = *inheritable;
+ current->cap_permitted = *permitted;
}
static inline void bprm_clear_caps(struct linux_binprm *bprm)
diff --git a/security/security.c b/security/security.c
index 346f21e..dca3738 100644
--- a/security/security.c
+++ b/security/security.c
@@ -145,20 +145,18 @@ int security_capget(struct task_struct *target,
return security_ops->capget(target, effective, inheritable, permitted);
}
-int security_capset_check(struct task_struct *target,
- kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
+int security_capset_check(kernel_cap_t *effective,
+ kernel_cap_t *inheritable,
+ kernel_cap_t *permitted)
{
- return security_ops->capset_check(target, effective, inheritable, permitted);
+ return security_ops->capset_check(effective, inheritable, permitted);
}
-void security_capset_set(struct task_struct *target,
- kernel_cap_t *effective,
- kernel_cap_t *inheritable,
- kernel_cap_t *permitted)
+void security_capset_set(kernel_cap_t *effective,
+ kernel_cap_t *inheritable,
+ kernel_cap_t *permitted)
{
- security_ops->capset_set(target, effective, inheritable, permitted);
+ security_ops->capset_set(effective, inheritable, permitted);
}
int security_capable(struct task_struct *tsk, int cap)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 378dc53..df99869 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1790,22 +1790,22 @@ static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
return secondary_ops->capget(target, effective, inheritable, permitted);
}
-static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
+static int selinux_capset_check(kernel_cap_t *effective,
kernel_cap_t *inheritable, kernel_cap_t *permitted)
{
int error;
- error = secondary_ops->capset_check(target, effective, inheritable, permitted);
+ error = secondary_ops->capset_check(effective, inheritable, permitted);
if (error)
return error;
- return task_has_perm(current, target, PROCESS__SETCAP);
+ return task_has_perm(current, current, PROCESS__SETCAP);
}
-static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
+static void selinux_capset_set(kernel_cap_t *effective,
kernel_cap_t *inheritable, kernel_cap_t *permitted)
{
- secondary_ops->capset_set(target, effective, inheritable, permitted);
+ secondary_ops->capset_set(effective, inheritable, permitted);
}
static int selinux_capable(struct task_struct *tsk, int cap, int audit)