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-rw-r--r--kernel/futex_compat.c202
1 files changed, 0 insertions, 202 deletions
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
deleted file mode 100644
index 83f830acbb5f..000000000000
--- a/kernel/futex_compat.c
+++ /dev/null
@@ -1,202 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * linux/kernel/futex_compat.c
- *
- * Futex compatibililty routines.
- *
- * Copyright 2006, Red Hat, Inc., Ingo Molnar
- */
-
-#include <linux/linkage.h>
-#include <linux/compat.h>
-#include <linux/nsproxy.h>
-#include <linux/futex.h>
-#include <linux/ptrace.h>
-#include <linux/syscalls.h>
-
-#include <linux/uaccess.h>
-
-
-/*
- * Fetch a robust-list pointer. Bit 0 signals PI futexes:
- */
-static inline int
-fetch_robust_entry(compat_uptr_t *uentry, struct robust_list __user **entry,
- compat_uptr_t __user *head, unsigned int *pi)
-{
- if (get_user(*uentry, head))
- return -EFAULT;
-
- *entry = compat_ptr((*uentry) & ~1);
- *pi = (unsigned int)(*uentry) & 1;
-
- return 0;
-}
-
-static void __user *futex_uaddr(struct robust_list __user *entry,
- compat_long_t futex_offset)
-{
- compat_uptr_t base = ptr_to_compat(entry);
- void __user *uaddr = compat_ptr(base + futex_offset);
-
- return uaddr;
-}
-
-/*
- * Walk curr->robust_list (very carefully, it's a userspace list!)
- * and mark any locks found there dead, and notify any waiters.
- *
- * We silently return on any sign of list-walking problem.
- */
-void compat_exit_robust_list(struct task_struct *curr)
-{
- struct compat_robust_list_head __user *head = curr->compat_robust_list;
- struct robust_list __user *entry, *next_entry, *pending;
- unsigned int limit = ROBUST_LIST_LIMIT, pi, pip;
- unsigned int uninitialized_var(next_pi);
- compat_uptr_t uentry, next_uentry, upending;
- compat_long_t futex_offset;
- int rc;
-
- if (!futex_cmpxchg_enabled)
- return;
-
- /*
- * Fetch the list head (which was registered earlier, via
- * sys_set_robust_list()):
- */
- if (fetch_robust_entry(&uentry, &entry, &head->list.next, &pi))
- return;
- /*
- * Fetch the relative futex offset:
- */
- if (get_user(futex_offset, &head->futex_offset))
- return;
- /*
- * Fetch any possibly pending lock-add first, and handle it
- * if it exists:
- */
- if (fetch_robust_entry(&upending, &pending,
- &head->list_op_pending, &pip))
- return;
-
- next_entry = NULL; /* avoid warning with gcc */
- while (entry != (struct robust_list __user *) &head->list) {
- /*
- * Fetch the next entry in the list before calling
- * handle_futex_death:
- */
- rc = fetch_robust_entry(&next_uentry, &next_entry,
- (compat_uptr_t __user *)&entry->next, &next_pi);
- /*
- * A pending lock might already be on the list, so
- * dont process it twice:
- */
- if (entry != pending) {
- void __user *uaddr = futex_uaddr(entry, futex_offset);
-
- if (handle_futex_death(uaddr, curr, pi))
- return;
- }
- if (rc)
- return;
- uentry = next_uentry;
- entry = next_entry;
- pi = next_pi;
- /*
- * Avoid excessively long or circular lists:
- */
- if (!--limit)
- break;
-
- cond_resched();
- }
- if (pending) {
- void __user *uaddr = futex_uaddr(pending, futex_offset);
-
- handle_futex_death(uaddr, curr, pip);
- }
-}
-
-COMPAT_SYSCALL_DEFINE2(set_robust_list,
- struct compat_robust_list_head __user *, head,
- compat_size_t, len)
-{
- if (!futex_cmpxchg_enabled)
- return -ENOSYS;
-
- if (unlikely(len != sizeof(*head)))
- return -EINVAL;
-
- current->compat_robust_list = head;
-
- return 0;
-}
-
-COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
- compat_uptr_t __user *, head_ptr,
- compat_size_t __user *, len_ptr)
-{
- struct compat_robust_list_head __user *head;
- unsigned long ret;
- struct task_struct *p;
-
- if (!futex_cmpxchg_enabled)
- return -ENOSYS;
-
- rcu_read_lock();
-
- ret = -ESRCH;
- if (!pid)
- p = current;
- else {
- p = find_task_by_vpid(pid);
- if (!p)
- goto err_unlock;
- }
-
- ret = -EPERM;
- if (!ptrace_may_access(p, PTRACE_MODE_READ_REALCREDS))
- goto err_unlock;
-
- head = p->compat_robust_list;
- rcu_read_unlock();
-
- if (put_user(sizeof(*head), len_ptr))
- return -EFAULT;
- return put_user(ptr_to_compat(head), head_ptr);
-
-err_unlock:
- rcu_read_unlock();
-
- return ret;
-}
-
-COMPAT_SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
- struct compat_timespec __user *, utime, u32 __user *, uaddr2,
- u32, val3)
-{
- struct timespec ts;
- ktime_t t, *tp = NULL;
- int val2 = 0;
- int cmd = op & FUTEX_CMD_MASK;
-
- if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI ||
- cmd == FUTEX_WAIT_BITSET ||
- cmd == FUTEX_WAIT_REQUEUE_PI)) {
- if (compat_get_timespec(&ts, utime))
- return -EFAULT;
- if (!timespec_valid(&ts))
- return -EINVAL;
-
- t = timespec_to_ktime(ts);
- if (cmd == FUTEX_WAIT)
- t = ktime_add_safe(ktime_get(), t);
- tp = &t;
- }
- if (cmd == FUTEX_REQUEUE || cmd == FUTEX_CMP_REQUEUE ||
- cmd == FUTEX_CMP_REQUEUE_PI || cmd == FUTEX_WAKE_OP)
- val2 = (int) (unsigned long) utime;
-
- return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);
-}