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-rw-r--r--kernel/capability.c227
1 files changed, 23 insertions, 204 deletions
diff --git a/kernel/capability.c b/kernel/capability.c
index adb262f83de..58b00519624 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;
}
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 12:44:25 +0000