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![Al Viro](/assets/img/avatar_default.png)
... and use unsafe_get_user(), while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
1439 lines
34 KiB
C
1439 lines
34 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* This file contains the procedures for the handling of select and poll
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*
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* Created for Linux based loosely upon Mathius Lattner's minix
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* patches by Peter MacDonald. Heavily edited by Linus.
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*
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* 4 February 1994
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* COFF/ELF binary emulation. If the process has the STICKY_TIMEOUTS
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* flag set in its personality we do *not* modify the given timeout
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* parameter to reflect time remaining.
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*
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* 24 January 2000
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* Changed sys_poll()/do_poll() to use PAGE_SIZE chunk-based allocation
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* of fds to overcome nfds < 16390 descriptors limit (Tigran Aivazian).
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*/
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#include <linux/kernel.h>
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#include <linux/sched/signal.h>
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#include <linux/sched/rt.h>
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#include <linux/syscalls.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/poll.h>
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#include <linux/personality.h> /* for STICKY_TIMEOUTS */
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/fs.h>
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#include <linux/rcupdate.h>
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#include <linux/hrtimer.h>
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#include <linux/freezer.h>
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#include <net/busy_poll.h>
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#include <linux/vmalloc.h>
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#include <linux/uaccess.h>
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/*
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* Estimate expected accuracy in ns from a timeval.
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*
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* After quite a bit of churning around, we've settled on
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* a simple thing of taking 0.1% of the timeout as the
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* slack, with a cap of 100 msec.
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* "nice" tasks get a 0.5% slack instead.
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*
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* Consider this comment an open invitation to come up with even
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* better solutions..
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*/
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#define MAX_SLACK (100 * NSEC_PER_MSEC)
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static long __estimate_accuracy(struct timespec64 *tv)
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{
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long slack;
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int divfactor = 1000;
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if (tv->tv_sec < 0)
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return 0;
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if (task_nice(current) > 0)
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divfactor = divfactor / 5;
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if (tv->tv_sec > MAX_SLACK / (NSEC_PER_SEC/divfactor))
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return MAX_SLACK;
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slack = tv->tv_nsec / divfactor;
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slack += tv->tv_sec * (NSEC_PER_SEC/divfactor);
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if (slack > MAX_SLACK)
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return MAX_SLACK;
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return slack;
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}
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u64 select_estimate_accuracy(struct timespec64 *tv)
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{
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u64 ret;
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struct timespec64 now;
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/*
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* Realtime tasks get a slack of 0 for obvious reasons.
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*/
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if (rt_task(current))
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return 0;
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ktime_get_ts64(&now);
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now = timespec64_sub(*tv, now);
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ret = __estimate_accuracy(&now);
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if (ret < current->timer_slack_ns)
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return current->timer_slack_ns;
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return ret;
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}
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struct poll_table_page {
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struct poll_table_page * next;
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struct poll_table_entry * entry;
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struct poll_table_entry entries[0];
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};
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#define POLL_TABLE_FULL(table) \
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((unsigned long)((table)->entry+1) > PAGE_SIZE + (unsigned long)(table))
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/*
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* Ok, Peter made a complicated, but straightforward multiple_wait() function.
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* I have rewritten this, taking some shortcuts: This code may not be easy to
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* follow, but it should be free of race-conditions, and it's practical. If you
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* understand what I'm doing here, then you understand how the linux
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* sleep/wakeup mechanism works.
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*
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* Two very simple procedures, poll_wait() and poll_freewait() make all the
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* work. poll_wait() is an inline-function defined in <linux/poll.h>,
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* as all select/poll functions have to call it to add an entry to the
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* poll table.
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*/
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static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
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poll_table *p);
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void poll_initwait(struct poll_wqueues *pwq)
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{
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init_poll_funcptr(&pwq->pt, __pollwait);
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pwq->polling_task = current;
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pwq->triggered = 0;
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pwq->error = 0;
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pwq->table = NULL;
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pwq->inline_index = 0;
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}
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EXPORT_SYMBOL(poll_initwait);
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static void free_poll_entry(struct poll_table_entry *entry)
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{
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remove_wait_queue(entry->wait_address, &entry->wait);
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fput(entry->filp);
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}
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void poll_freewait(struct poll_wqueues *pwq)
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{
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struct poll_table_page * p = pwq->table;
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int i;
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for (i = 0; i < pwq->inline_index; i++)
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free_poll_entry(pwq->inline_entries + i);
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while (p) {
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struct poll_table_entry * entry;
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struct poll_table_page *old;
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entry = p->entry;
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do {
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entry--;
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free_poll_entry(entry);
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} while (entry > p->entries);
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old = p;
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p = p->next;
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free_page((unsigned long) old);
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}
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}
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EXPORT_SYMBOL(poll_freewait);
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static struct poll_table_entry *poll_get_entry(struct poll_wqueues *p)
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{
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struct poll_table_page *table = p->table;
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if (p->inline_index < N_INLINE_POLL_ENTRIES)
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return p->inline_entries + p->inline_index++;
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if (!table || POLL_TABLE_FULL(table)) {
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struct poll_table_page *new_table;
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new_table = (struct poll_table_page *) __get_free_page(GFP_KERNEL);
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if (!new_table) {
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p->error = -ENOMEM;
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return NULL;
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}
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new_table->entry = new_table->entries;
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new_table->next = table;
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p->table = new_table;
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table = new_table;
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}
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return table->entry++;
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}
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static int __pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key)
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{
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struct poll_wqueues *pwq = wait->private;
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DECLARE_WAITQUEUE(dummy_wait, pwq->polling_task);
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/*
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* Although this function is called under waitqueue lock, LOCK
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* doesn't imply write barrier and the users expect write
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* barrier semantics on wakeup functions. The following
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* smp_wmb() is equivalent to smp_wmb() in try_to_wake_up()
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* and is paired with smp_store_mb() in poll_schedule_timeout.
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*/
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smp_wmb();
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pwq->triggered = 1;
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/*
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* Perform the default wake up operation using a dummy
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* waitqueue.
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*
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* TODO: This is hacky but there currently is no interface to
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* pass in @sync. @sync is scheduled to be removed and once
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* that happens, wake_up_process() can be used directly.
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*/
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return default_wake_function(&dummy_wait, mode, sync, key);
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}
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static int pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key)
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{
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struct poll_table_entry *entry;
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entry = container_of(wait, struct poll_table_entry, wait);
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if (key && !(key_to_poll(key) & entry->key))
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return 0;
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return __pollwake(wait, mode, sync, key);
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}
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/* Add a new entry */
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static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
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poll_table *p)
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{
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struct poll_wqueues *pwq = container_of(p, struct poll_wqueues, pt);
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struct poll_table_entry *entry = poll_get_entry(pwq);
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if (!entry)
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return;
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entry->filp = get_file(filp);
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entry->wait_address = wait_address;
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entry->key = p->_key;
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init_waitqueue_func_entry(&entry->wait, pollwake);
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entry->wait.private = pwq;
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add_wait_queue(wait_address, &entry->wait);
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}
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static int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
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ktime_t *expires, unsigned long slack)
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{
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int rc = -EINTR;
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set_current_state(state);
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if (!pwq->triggered)
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rc = schedule_hrtimeout_range(expires, slack, HRTIMER_MODE_ABS);
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__set_current_state(TASK_RUNNING);
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/*
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* Prepare for the next iteration.
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*
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* The following smp_store_mb() serves two purposes. First, it's
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* the counterpart rmb of the wmb in pollwake() such that data
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* written before wake up is always visible after wake up.
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* Second, the full barrier guarantees that triggered clearing
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* doesn't pass event check of the next iteration. Note that
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* this problem doesn't exist for the first iteration as
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* add_wait_queue() has full barrier semantics.
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*/
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smp_store_mb(pwq->triggered, 0);
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return rc;
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}
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/**
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* poll_select_set_timeout - helper function to setup the timeout value
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* @to: pointer to timespec64 variable for the final timeout
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* @sec: seconds (from user space)
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* @nsec: nanoseconds (from user space)
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*
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* Note, we do not use a timespec for the user space value here, That
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* way we can use the function for timeval and compat interfaces as well.
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*
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* Returns -EINVAL if sec/nsec are not normalized. Otherwise 0.
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*/
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int poll_select_set_timeout(struct timespec64 *to, time64_t sec, long nsec)
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{
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struct timespec64 ts = {.tv_sec = sec, .tv_nsec = nsec};
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if (!timespec64_valid(&ts))
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return -EINVAL;
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/* Optimize for the zero timeout value here */
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if (!sec && !nsec) {
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to->tv_sec = to->tv_nsec = 0;
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} else {
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ktime_get_ts64(to);
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*to = timespec64_add_safe(*to, ts);
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}
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return 0;
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}
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enum poll_time_type {
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PT_TIMEVAL = 0,
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PT_OLD_TIMEVAL = 1,
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PT_TIMESPEC = 2,
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PT_OLD_TIMESPEC = 3,
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};
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static int poll_select_finish(struct timespec64 *end_time,
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void __user *p,
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enum poll_time_type pt_type, int ret)
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{
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struct timespec64 rts;
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restore_saved_sigmask_unless(ret == -ERESTARTNOHAND);
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if (!p)
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return ret;
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if (current->personality & STICKY_TIMEOUTS)
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goto sticky;
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/* No update for zero timeout */
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if (!end_time->tv_sec && !end_time->tv_nsec)
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return ret;
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ktime_get_ts64(&rts);
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rts = timespec64_sub(*end_time, rts);
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if (rts.tv_sec < 0)
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rts.tv_sec = rts.tv_nsec = 0;
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switch (pt_type) {
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case PT_TIMEVAL:
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{
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struct __kernel_old_timeval rtv;
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if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec))
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memset(&rtv, 0, sizeof(rtv));
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rtv.tv_sec = rts.tv_sec;
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rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
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if (!copy_to_user(p, &rtv, sizeof(rtv)))
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return ret;
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}
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break;
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case PT_OLD_TIMEVAL:
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{
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struct old_timeval32 rtv;
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rtv.tv_sec = rts.tv_sec;
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rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
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if (!copy_to_user(p, &rtv, sizeof(rtv)))
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return ret;
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}
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break;
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case PT_TIMESPEC:
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if (!put_timespec64(&rts, p))
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return ret;
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break;
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case PT_OLD_TIMESPEC:
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if (!put_old_timespec32(&rts, p))
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return ret;
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break;
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default:
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BUG();
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}
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/*
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* If an application puts its timeval in read-only memory, we
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* don't want the Linux-specific update to the timeval to
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* cause a fault after the select has completed
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* successfully. However, because we're not updating the
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* timeval, we can't restart the system call.
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*/
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sticky:
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if (ret == -ERESTARTNOHAND)
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ret = -EINTR;
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return ret;
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}
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/*
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* Scalable version of the fd_set.
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*/
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typedef struct {
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unsigned long *in, *out, *ex;
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unsigned long *res_in, *res_out, *res_ex;
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} fd_set_bits;
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/*
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* How many longwords for "nr" bits?
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*/
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#define FDS_BITPERLONG (8*sizeof(long))
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#define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG)
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#define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long))
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/*
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* Use "unsigned long" accesses to let user-mode fd_set's be long-aligned.
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*/
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static inline
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int get_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
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{
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nr = FDS_BYTES(nr);
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if (ufdset)
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return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0;
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memset(fdset, 0, nr);
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return 0;
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}
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static inline unsigned long __must_check
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set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
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{
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if (ufdset)
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return __copy_to_user(ufdset, fdset, FDS_BYTES(nr));
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return 0;
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}
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static inline
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void zero_fd_set(unsigned long nr, unsigned long *fdset)
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{
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memset(fdset, 0, FDS_BYTES(nr));
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}
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#define FDS_IN(fds, n) (fds->in + n)
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#define FDS_OUT(fds, n) (fds->out + n)
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#define FDS_EX(fds, n) (fds->ex + n)
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#define BITS(fds, n) (*FDS_IN(fds, n)|*FDS_OUT(fds, n)|*FDS_EX(fds, n))
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|
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static int max_select_fd(unsigned long n, fd_set_bits *fds)
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{
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unsigned long *open_fds;
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unsigned long set;
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int max;
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struct fdtable *fdt;
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|
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/* handle last in-complete long-word first */
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set = ~(~0UL << (n & (BITS_PER_LONG-1)));
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n /= BITS_PER_LONG;
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fdt = files_fdtable(current->files);
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open_fds = fdt->open_fds + n;
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max = 0;
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if (set) {
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set &= BITS(fds, n);
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if (set) {
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if (!(set & ~*open_fds))
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goto get_max;
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return -EBADF;
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}
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}
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while (n) {
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open_fds--;
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n--;
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set = BITS(fds, n);
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if (!set)
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continue;
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if (set & ~*open_fds)
|
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return -EBADF;
|
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if (max)
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continue;
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get_max:
|
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do {
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max++;
|
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set >>= 1;
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} while (set);
|
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max += n * BITS_PER_LONG;
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}
|
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|
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return max;
|
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}
|
|
|
|
#define POLLIN_SET (EPOLLRDNORM | EPOLLRDBAND | EPOLLIN | EPOLLHUP | EPOLLERR)
|
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#define POLLOUT_SET (EPOLLWRBAND | EPOLLWRNORM | EPOLLOUT | EPOLLERR)
|
|
#define POLLEX_SET (EPOLLPRI)
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|
|
|
static inline void wait_key_set(poll_table *wait, unsigned long in,
|
|
unsigned long out, unsigned long bit,
|
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__poll_t ll_flag)
|
|
{
|
|
wait->_key = POLLEX_SET | ll_flag;
|
|
if (in & bit)
|
|
wait->_key |= POLLIN_SET;
|
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if (out & bit)
|
|
wait->_key |= POLLOUT_SET;
|
|
}
|
|
|
|
static int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time)
|
|
{
|
|
ktime_t expire, *to = NULL;
|
|
struct poll_wqueues table;
|
|
poll_table *wait;
|
|
int retval, i, timed_out = 0;
|
|
u64 slack = 0;
|
|
__poll_t busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0;
|
|
unsigned long busy_start = 0;
|
|
|
|
rcu_read_lock();
|
|
retval = max_select_fd(n, fds);
|
|
rcu_read_unlock();
|
|
|
|
if (retval < 0)
|
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return retval;
|
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n = retval;
|
|
|
|
poll_initwait(&table);
|
|
wait = &table.pt;
|
|
if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
|
|
wait->_qproc = NULL;
|
|
timed_out = 1;
|
|
}
|
|
|
|
if (end_time && !timed_out)
|
|
slack = select_estimate_accuracy(end_time);
|
|
|
|
retval = 0;
|
|
for (;;) {
|
|
unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp;
|
|
bool can_busy_loop = false;
|
|
|
|
inp = fds->in; outp = fds->out; exp = fds->ex;
|
|
rinp = fds->res_in; routp = fds->res_out; rexp = fds->res_ex;
|
|
|
|
for (i = 0; i < n; ++rinp, ++routp, ++rexp) {
|
|
unsigned long in, out, ex, all_bits, bit = 1, j;
|
|
unsigned long res_in = 0, res_out = 0, res_ex = 0;
|
|
__poll_t mask;
|
|
|
|
in = *inp++; out = *outp++; ex = *exp++;
|
|
all_bits = in | out | ex;
|
|
if (all_bits == 0) {
|
|
i += BITS_PER_LONG;
|
|
continue;
|
|
}
|
|
|
|
for (j = 0; j < BITS_PER_LONG; ++j, ++i, bit <<= 1) {
|
|
struct fd f;
|
|
if (i >= n)
|
|
break;
|
|
if (!(bit & all_bits))
|
|
continue;
|
|
f = fdget(i);
|
|
if (f.file) {
|
|
wait_key_set(wait, in, out, bit,
|
|
busy_flag);
|
|
mask = vfs_poll(f.file, wait);
|
|
|
|
fdput(f);
|
|
if ((mask & POLLIN_SET) && (in & bit)) {
|
|
res_in |= bit;
|
|
retval++;
|
|
wait->_qproc = NULL;
|
|
}
|
|
if ((mask & POLLOUT_SET) && (out & bit)) {
|
|
res_out |= bit;
|
|
retval++;
|
|
wait->_qproc = NULL;
|
|
}
|
|
if ((mask & POLLEX_SET) && (ex & bit)) {
|
|
res_ex |= bit;
|
|
retval++;
|
|
wait->_qproc = NULL;
|
|
}
|
|
/* got something, stop busy polling */
|
|
if (retval) {
|
|
can_busy_loop = false;
|
|
busy_flag = 0;
|
|
|
|
/*
|
|
* only remember a returned
|
|
* POLL_BUSY_LOOP if we asked for it
|
|
*/
|
|
} else if (busy_flag & mask)
|
|
can_busy_loop = true;
|
|
|
|
}
|
|
}
|
|
if (res_in)
|
|
*rinp = res_in;
|
|
if (res_out)
|
|
*routp = res_out;
|
|
if (res_ex)
|
|
*rexp = res_ex;
|
|
cond_resched();
|
|
}
|
|
wait->_qproc = NULL;
|
|
if (retval || timed_out || signal_pending(current))
|
|
break;
|
|
if (table.error) {
|
|
retval = table.error;
|
|
break;
|
|
}
|
|
|
|
/* only if found POLL_BUSY_LOOP sockets && not out of time */
|
|
if (can_busy_loop && !need_resched()) {
|
|
if (!busy_start) {
|
|
busy_start = busy_loop_current_time();
|
|
continue;
|
|
}
|
|
if (!busy_loop_timeout(busy_start))
|
|
continue;
|
|
}
|
|
busy_flag = 0;
|
|
|
|
/*
|
|
* If this is the first loop and we have a timeout
|
|
* given, then we convert to ktime_t and set the to
|
|
* pointer to the expiry value.
|
|
*/
|
|
if (end_time && !to) {
|
|
expire = timespec64_to_ktime(*end_time);
|
|
to = &expire;
|
|
}
|
|
|
|
if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE,
|
|
to, slack))
|
|
timed_out = 1;
|
|
}
|
|
|
|
poll_freewait(&table);
|
|
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* We can actually return ERESTARTSYS instead of EINTR, but I'd
|
|
* like to be certain this leads to no problems. So I return
|
|
* EINTR just for safety.
|
|
*
|
|
* Update: ERESTARTSYS breaks at least the xview clock binary, so
|
|
* I'm trying ERESTARTNOHAND which restart only when you want to.
|
|
*/
|
|
int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
|
|
fd_set __user *exp, struct timespec64 *end_time)
|
|
{
|
|
fd_set_bits fds;
|
|
void *bits;
|
|
int ret, max_fds;
|
|
size_t size, alloc_size;
|
|
struct fdtable *fdt;
|
|
/* Allocate small arguments on the stack to save memory and be faster */
|
|
long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
|
|
|
|
ret = -EINVAL;
|
|
if (n < 0)
|
|
goto out_nofds;
|
|
|
|
/* max_fds can increase, so grab it once to avoid race */
|
|
rcu_read_lock();
|
|
fdt = files_fdtable(current->files);
|
|
max_fds = fdt->max_fds;
|
|
rcu_read_unlock();
|
|
if (n > max_fds)
|
|
n = max_fds;
|
|
|
|
/*
|
|
* We need 6 bitmaps (in/out/ex for both incoming and outgoing),
|
|
* since we used fdset we need to allocate memory in units of
|
|
* long-words.
|
|
*/
|
|
size = FDS_BYTES(n);
|
|
bits = stack_fds;
|
|
if (size > sizeof(stack_fds) / 6) {
|
|
/* Not enough space in on-stack array; must use kmalloc */
|
|
ret = -ENOMEM;
|
|
if (size > (SIZE_MAX / 6))
|
|
goto out_nofds;
|
|
|
|
alloc_size = 6 * size;
|
|
bits = kvmalloc(alloc_size, GFP_KERNEL);
|
|
if (!bits)
|
|
goto out_nofds;
|
|
}
|
|
fds.in = bits;
|
|
fds.out = bits + size;
|
|
fds.ex = bits + 2*size;
|
|
fds.res_in = bits + 3*size;
|
|
fds.res_out = bits + 4*size;
|
|
fds.res_ex = bits + 5*size;
|
|
|
|
if ((ret = get_fd_set(n, inp, fds.in)) ||
|
|
(ret = get_fd_set(n, outp, fds.out)) ||
|
|
(ret = get_fd_set(n, exp, fds.ex)))
|
|
goto out;
|
|
zero_fd_set(n, fds.res_in);
|
|
zero_fd_set(n, fds.res_out);
|
|
zero_fd_set(n, fds.res_ex);
|
|
|
|
ret = do_select(n, &fds, end_time);
|
|
|
|
if (ret < 0)
|
|
goto out;
|
|
if (!ret) {
|
|
ret = -ERESTARTNOHAND;
|
|
if (signal_pending(current))
|
|
goto out;
|
|
ret = 0;
|
|
}
|
|
|
|
if (set_fd_set(n, inp, fds.res_in) ||
|
|
set_fd_set(n, outp, fds.res_out) ||
|
|
set_fd_set(n, exp, fds.res_ex))
|
|
ret = -EFAULT;
|
|
|
|
out:
|
|
if (bits != stack_fds)
|
|
kvfree(bits);
|
|
out_nofds:
|
|
return ret;
|
|
}
|
|
|
|
static int kern_select(int n, fd_set __user *inp, fd_set __user *outp,
|
|
fd_set __user *exp, struct __kernel_old_timeval __user *tvp)
|
|
{
|
|
struct timespec64 end_time, *to = NULL;
|
|
struct __kernel_old_timeval tv;
|
|
int ret;
|
|
|
|
if (tvp) {
|
|
if (copy_from_user(&tv, tvp, sizeof(tv)))
|
|
return -EFAULT;
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to,
|
|
tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
|
|
(tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = core_sys_select(n, inp, outp, exp, to);
|
|
return poll_select_finish(&end_time, tvp, PT_TIMEVAL, ret);
|
|
}
|
|
|
|
SYSCALL_DEFINE5(select, int, n, fd_set __user *, inp, fd_set __user *, outp,
|
|
fd_set __user *, exp, struct __kernel_old_timeval __user *, tvp)
|
|
{
|
|
return kern_select(n, inp, outp, exp, tvp);
|
|
}
|
|
|
|
static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp,
|
|
fd_set __user *exp, void __user *tsp,
|
|
const sigset_t __user *sigmask, size_t sigsetsize,
|
|
enum poll_time_type type)
|
|
{
|
|
struct timespec64 ts, end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (tsp) {
|
|
switch (type) {
|
|
case PT_TIMESPEC:
|
|
if (get_timespec64(&ts, tsp))
|
|
return -EFAULT;
|
|
break;
|
|
case PT_OLD_TIMESPEC:
|
|
if (get_old_timespec32(&ts, tsp))
|
|
return -EFAULT;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = set_user_sigmask(sigmask, sigsetsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = core_sys_select(n, inp, outp, exp, to);
|
|
return poll_select_finish(&end_time, tsp, type, ret);
|
|
}
|
|
|
|
/*
|
|
* Most architectures can't handle 7-argument syscalls. So we provide a
|
|
* 6-argument version where the sixth argument is a pointer to a structure
|
|
* which has a pointer to the sigset_t itself followed by a size_t containing
|
|
* the sigset size.
|
|
*/
|
|
struct sigset_argpack {
|
|
sigset_t __user *p;
|
|
size_t size;
|
|
};
|
|
|
|
static inline int get_sigset_argpack(struct sigset_argpack *to,
|
|
struct sigset_argpack __user *from)
|
|
{
|
|
// the path is hot enough for overhead of copy_from_user() to matter
|
|
if (from) {
|
|
if (!user_read_access_begin(from, sizeof(*from)))
|
|
return -EFAULT;
|
|
unsafe_get_user(to->p, &from->p, Efault);
|
|
unsafe_get_user(to->size, &from->size, Efault);
|
|
user_read_access_end();
|
|
}
|
|
return 0;
|
|
Efault:
|
|
user_access_end();
|
|
return -EFAULT;
|
|
}
|
|
|
|
SYSCALL_DEFINE6(pselect6, int, n, fd_set __user *, inp, fd_set __user *, outp,
|
|
fd_set __user *, exp, struct __kernel_timespec __user *, tsp,
|
|
void __user *, sig)
|
|
{
|
|
struct sigset_argpack x = {NULL, 0};
|
|
|
|
if (get_sigset_argpack(&x, sig))
|
|
return -EFAULT;
|
|
|
|
return do_pselect(n, inp, outp, exp, tsp, x.p, x.size, PT_TIMESPEC);
|
|
}
|
|
|
|
#if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT)
|
|
|
|
SYSCALL_DEFINE6(pselect6_time32, int, n, fd_set __user *, inp, fd_set __user *, outp,
|
|
fd_set __user *, exp, struct old_timespec32 __user *, tsp,
|
|
void __user *, sig)
|
|
{
|
|
struct sigset_argpack x = {NULL, 0};
|
|
|
|
if (get_sigset_argpack(&x, sig))
|
|
return -EFAULT;
|
|
|
|
return do_pselect(n, inp, outp, exp, tsp, x.p, x.size, PT_OLD_TIMESPEC);
|
|
}
|
|
|
|
#endif
|
|
|
|
#ifdef __ARCH_WANT_SYS_OLD_SELECT
|
|
struct sel_arg_struct {
|
|
unsigned long n;
|
|
fd_set __user *inp, *outp, *exp;
|
|
struct __kernel_old_timeval __user *tvp;
|
|
};
|
|
|
|
SYSCALL_DEFINE1(old_select, struct sel_arg_struct __user *, arg)
|
|
{
|
|
struct sel_arg_struct a;
|
|
|
|
if (copy_from_user(&a, arg, sizeof(a)))
|
|
return -EFAULT;
|
|
return kern_select(a.n, a.inp, a.outp, a.exp, a.tvp);
|
|
}
|
|
#endif
|
|
|
|
struct poll_list {
|
|
struct poll_list *next;
|
|
int len;
|
|
struct pollfd entries[0];
|
|
};
|
|
|
|
#define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd))
|
|
|
|
/*
|
|
* Fish for pollable events on the pollfd->fd file descriptor. We're only
|
|
* interested in events matching the pollfd->events mask, and the result
|
|
* matching that mask is both recorded in pollfd->revents and returned. The
|
|
* pwait poll_table will be used by the fd-provided poll handler for waiting,
|
|
* if pwait->_qproc is non-NULL.
|
|
*/
|
|
static inline __poll_t do_pollfd(struct pollfd *pollfd, poll_table *pwait,
|
|
bool *can_busy_poll,
|
|
__poll_t busy_flag)
|
|
{
|
|
int fd = pollfd->fd;
|
|
__poll_t mask = 0, filter;
|
|
struct fd f;
|
|
|
|
if (fd < 0)
|
|
goto out;
|
|
mask = EPOLLNVAL;
|
|
f = fdget(fd);
|
|
if (!f.file)
|
|
goto out;
|
|
|
|
/* userland u16 ->events contains POLL... bitmap */
|
|
filter = demangle_poll(pollfd->events) | EPOLLERR | EPOLLHUP;
|
|
pwait->_key = filter | busy_flag;
|
|
mask = vfs_poll(f.file, pwait);
|
|
if (mask & busy_flag)
|
|
*can_busy_poll = true;
|
|
mask &= filter; /* Mask out unneeded events. */
|
|
fdput(f);
|
|
|
|
out:
|
|
/* ... and so does ->revents */
|
|
pollfd->revents = mangle_poll(mask);
|
|
return mask;
|
|
}
|
|
|
|
static int do_poll(struct poll_list *list, struct poll_wqueues *wait,
|
|
struct timespec64 *end_time)
|
|
{
|
|
poll_table* pt = &wait->pt;
|
|
ktime_t expire, *to = NULL;
|
|
int timed_out = 0, count = 0;
|
|
u64 slack = 0;
|
|
__poll_t busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0;
|
|
unsigned long busy_start = 0;
|
|
|
|
/* Optimise the no-wait case */
|
|
if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
|
|
pt->_qproc = NULL;
|
|
timed_out = 1;
|
|
}
|
|
|
|
if (end_time && !timed_out)
|
|
slack = select_estimate_accuracy(end_time);
|
|
|
|
for (;;) {
|
|
struct poll_list *walk;
|
|
bool can_busy_loop = false;
|
|
|
|
for (walk = list; walk != NULL; walk = walk->next) {
|
|
struct pollfd * pfd, * pfd_end;
|
|
|
|
pfd = walk->entries;
|
|
pfd_end = pfd + walk->len;
|
|
for (; pfd != pfd_end; pfd++) {
|
|
/*
|
|
* Fish for events. If we found one, record it
|
|
* and kill poll_table->_qproc, so we don't
|
|
* needlessly register any other waiters after
|
|
* this. They'll get immediately deregistered
|
|
* when we break out and return.
|
|
*/
|
|
if (do_pollfd(pfd, pt, &can_busy_loop,
|
|
busy_flag)) {
|
|
count++;
|
|
pt->_qproc = NULL;
|
|
/* found something, stop busy polling */
|
|
busy_flag = 0;
|
|
can_busy_loop = false;
|
|
}
|
|
}
|
|
}
|
|
/*
|
|
* All waiters have already been registered, so don't provide
|
|
* a poll_table->_qproc to them on the next loop iteration.
|
|
*/
|
|
pt->_qproc = NULL;
|
|
if (!count) {
|
|
count = wait->error;
|
|
if (signal_pending(current))
|
|
count = -ERESTARTNOHAND;
|
|
}
|
|
if (count || timed_out)
|
|
break;
|
|
|
|
/* only if found POLL_BUSY_LOOP sockets && not out of time */
|
|
if (can_busy_loop && !need_resched()) {
|
|
if (!busy_start) {
|
|
busy_start = busy_loop_current_time();
|
|
continue;
|
|
}
|
|
if (!busy_loop_timeout(busy_start))
|
|
continue;
|
|
}
|
|
busy_flag = 0;
|
|
|
|
/*
|
|
* If this is the first loop and we have a timeout
|
|
* given, then we convert to ktime_t and set the to
|
|
* pointer to the expiry value.
|
|
*/
|
|
if (end_time && !to) {
|
|
expire = timespec64_to_ktime(*end_time);
|
|
to = &expire;
|
|
}
|
|
|
|
if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE, to, slack))
|
|
timed_out = 1;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
#define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \
|
|
sizeof(struct pollfd))
|
|
|
|
static int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
|
|
struct timespec64 *end_time)
|
|
{
|
|
struct poll_wqueues table;
|
|
int err = -EFAULT, fdcount, len;
|
|
/* Allocate small arguments on the stack to save memory and be
|
|
faster - use long to make sure the buffer is aligned properly
|
|
on 64 bit archs to avoid unaligned access */
|
|
long stack_pps[POLL_STACK_ALLOC/sizeof(long)];
|
|
struct poll_list *const head = (struct poll_list *)stack_pps;
|
|
struct poll_list *walk = head;
|
|
unsigned long todo = nfds;
|
|
|
|
if (nfds > rlimit(RLIMIT_NOFILE))
|
|
return -EINVAL;
|
|
|
|
len = min_t(unsigned int, nfds, N_STACK_PPS);
|
|
for (;;) {
|
|
walk->next = NULL;
|
|
walk->len = len;
|
|
if (!len)
|
|
break;
|
|
|
|
if (copy_from_user(walk->entries, ufds + nfds-todo,
|
|
sizeof(struct pollfd) * walk->len))
|
|
goto out_fds;
|
|
|
|
todo -= walk->len;
|
|
if (!todo)
|
|
break;
|
|
|
|
len = min(todo, POLLFD_PER_PAGE);
|
|
walk = walk->next = kmalloc(struct_size(walk, entries, len),
|
|
GFP_KERNEL);
|
|
if (!walk) {
|
|
err = -ENOMEM;
|
|
goto out_fds;
|
|
}
|
|
}
|
|
|
|
poll_initwait(&table);
|
|
fdcount = do_poll(head, &table, end_time);
|
|
poll_freewait(&table);
|
|
|
|
for (walk = head; walk; walk = walk->next) {
|
|
struct pollfd *fds = walk->entries;
|
|
int j;
|
|
|
|
for (j = 0; j < walk->len; j++, ufds++)
|
|
if (__put_user(fds[j].revents, &ufds->revents))
|
|
goto out_fds;
|
|
}
|
|
|
|
err = fdcount;
|
|
out_fds:
|
|
walk = head->next;
|
|
while (walk) {
|
|
struct poll_list *pos = walk;
|
|
walk = walk->next;
|
|
kfree(pos);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static long do_restart_poll(struct restart_block *restart_block)
|
|
{
|
|
struct pollfd __user *ufds = restart_block->poll.ufds;
|
|
int nfds = restart_block->poll.nfds;
|
|
struct timespec64 *to = NULL, end_time;
|
|
int ret;
|
|
|
|
if (restart_block->poll.has_timeout) {
|
|
end_time.tv_sec = restart_block->poll.tv_sec;
|
|
end_time.tv_nsec = restart_block->poll.tv_nsec;
|
|
to = &end_time;
|
|
}
|
|
|
|
ret = do_sys_poll(ufds, nfds, to);
|
|
|
|
if (ret == -ERESTARTNOHAND) {
|
|
restart_block->fn = do_restart_poll;
|
|
ret = -ERESTART_RESTARTBLOCK;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
|
|
int, timeout_msecs)
|
|
{
|
|
struct timespec64 end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (timeout_msecs >= 0) {
|
|
to = &end_time;
|
|
poll_select_set_timeout(to, timeout_msecs / MSEC_PER_SEC,
|
|
NSEC_PER_MSEC * (timeout_msecs % MSEC_PER_SEC));
|
|
}
|
|
|
|
ret = do_sys_poll(ufds, nfds, to);
|
|
|
|
if (ret == -ERESTARTNOHAND) {
|
|
struct restart_block *restart_block;
|
|
|
|
restart_block = ¤t->restart_block;
|
|
restart_block->fn = do_restart_poll;
|
|
restart_block->poll.ufds = ufds;
|
|
restart_block->poll.nfds = nfds;
|
|
|
|
if (timeout_msecs >= 0) {
|
|
restart_block->poll.tv_sec = end_time.tv_sec;
|
|
restart_block->poll.tv_nsec = end_time.tv_nsec;
|
|
restart_block->poll.has_timeout = 1;
|
|
} else
|
|
restart_block->poll.has_timeout = 0;
|
|
|
|
ret = -ERESTART_RESTARTBLOCK;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
|
|
struct __kernel_timespec __user *, tsp, const sigset_t __user *, sigmask,
|
|
size_t, sigsetsize)
|
|
{
|
|
struct timespec64 ts, end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (tsp) {
|
|
if (get_timespec64(&ts, tsp))
|
|
return -EFAULT;
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = set_user_sigmask(sigmask, sigsetsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = do_sys_poll(ufds, nfds, to);
|
|
return poll_select_finish(&end_time, tsp, PT_TIMESPEC, ret);
|
|
}
|
|
|
|
#if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT)
|
|
|
|
SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds, unsigned int, nfds,
|
|
struct old_timespec32 __user *, tsp, const sigset_t __user *, sigmask,
|
|
size_t, sigsetsize)
|
|
{
|
|
struct timespec64 ts, end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (tsp) {
|
|
if (get_old_timespec32(&ts, tsp))
|
|
return -EFAULT;
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = set_user_sigmask(sigmask, sigsetsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = do_sys_poll(ufds, nfds, to);
|
|
return poll_select_finish(&end_time, tsp, PT_OLD_TIMESPEC, ret);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
#define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
|
|
|
|
/*
|
|
* Ooo, nasty. We need here to frob 32-bit unsigned longs to
|
|
* 64-bit unsigned longs.
|
|
*/
|
|
static
|
|
int compat_get_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
|
|
unsigned long *fdset)
|
|
{
|
|
if (ufdset) {
|
|
return compat_get_bitmap(fdset, ufdset, nr);
|
|
} else {
|
|
zero_fd_set(nr, fdset);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static
|
|
int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
|
|
unsigned long *fdset)
|
|
{
|
|
if (!ufdset)
|
|
return 0;
|
|
return compat_put_bitmap(ufdset, fdset, nr);
|
|
}
|
|
|
|
|
|
/*
|
|
* This is a virtual copy of sys_select from fs/select.c and probably
|
|
* should be compared to it from time to time
|
|
*/
|
|
|
|
/*
|
|
* We can actually return ERESTARTSYS instead of EINTR, but I'd
|
|
* like to be certain this leads to no problems. So I return
|
|
* EINTR just for safety.
|
|
*
|
|
* Update: ERESTARTSYS breaks at least the xview clock binary, so
|
|
* I'm trying ERESTARTNOHAND which restart only when you want to.
|
|
*/
|
|
static int compat_core_sys_select(int n, compat_ulong_t __user *inp,
|
|
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
|
|
struct timespec64 *end_time)
|
|
{
|
|
fd_set_bits fds;
|
|
void *bits;
|
|
int size, max_fds, ret = -EINVAL;
|
|
struct fdtable *fdt;
|
|
long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
|
|
|
|
if (n < 0)
|
|
goto out_nofds;
|
|
|
|
/* max_fds can increase, so grab it once to avoid race */
|
|
rcu_read_lock();
|
|
fdt = files_fdtable(current->files);
|
|
max_fds = fdt->max_fds;
|
|
rcu_read_unlock();
|
|
if (n > max_fds)
|
|
n = max_fds;
|
|
|
|
/*
|
|
* We need 6 bitmaps (in/out/ex for both incoming and outgoing),
|
|
* since we used fdset we need to allocate memory in units of
|
|
* long-words.
|
|
*/
|
|
size = FDS_BYTES(n);
|
|
bits = stack_fds;
|
|
if (size > sizeof(stack_fds) / 6) {
|
|
bits = kmalloc_array(6, size, GFP_KERNEL);
|
|
ret = -ENOMEM;
|
|
if (!bits)
|
|
goto out_nofds;
|
|
}
|
|
fds.in = (unsigned long *) bits;
|
|
fds.out = (unsigned long *) (bits + size);
|
|
fds.ex = (unsigned long *) (bits + 2*size);
|
|
fds.res_in = (unsigned long *) (bits + 3*size);
|
|
fds.res_out = (unsigned long *) (bits + 4*size);
|
|
fds.res_ex = (unsigned long *) (bits + 5*size);
|
|
|
|
if ((ret = compat_get_fd_set(n, inp, fds.in)) ||
|
|
(ret = compat_get_fd_set(n, outp, fds.out)) ||
|
|
(ret = compat_get_fd_set(n, exp, fds.ex)))
|
|
goto out;
|
|
zero_fd_set(n, fds.res_in);
|
|
zero_fd_set(n, fds.res_out);
|
|
zero_fd_set(n, fds.res_ex);
|
|
|
|
ret = do_select(n, &fds, end_time);
|
|
|
|
if (ret < 0)
|
|
goto out;
|
|
if (!ret) {
|
|
ret = -ERESTARTNOHAND;
|
|
if (signal_pending(current))
|
|
goto out;
|
|
ret = 0;
|
|
}
|
|
|
|
if (compat_set_fd_set(n, inp, fds.res_in) ||
|
|
compat_set_fd_set(n, outp, fds.res_out) ||
|
|
compat_set_fd_set(n, exp, fds.res_ex))
|
|
ret = -EFAULT;
|
|
out:
|
|
if (bits != stack_fds)
|
|
kfree(bits);
|
|
out_nofds:
|
|
return ret;
|
|
}
|
|
|
|
static int do_compat_select(int n, compat_ulong_t __user *inp,
|
|
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
|
|
struct old_timeval32 __user *tvp)
|
|
{
|
|
struct timespec64 end_time, *to = NULL;
|
|
struct old_timeval32 tv;
|
|
int ret;
|
|
|
|
if (tvp) {
|
|
if (copy_from_user(&tv, tvp, sizeof(tv)))
|
|
return -EFAULT;
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to,
|
|
tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
|
|
(tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = compat_core_sys_select(n, inp, outp, exp, to);
|
|
return poll_select_finish(&end_time, tvp, PT_OLD_TIMEVAL, ret);
|
|
}
|
|
|
|
COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp,
|
|
compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
|
|
struct old_timeval32 __user *, tvp)
|
|
{
|
|
return do_compat_select(n, inp, outp, exp, tvp);
|
|
}
|
|
|
|
struct compat_sel_arg_struct {
|
|
compat_ulong_t n;
|
|
compat_uptr_t inp;
|
|
compat_uptr_t outp;
|
|
compat_uptr_t exp;
|
|
compat_uptr_t tvp;
|
|
};
|
|
|
|
COMPAT_SYSCALL_DEFINE1(old_select, struct compat_sel_arg_struct __user *, arg)
|
|
{
|
|
struct compat_sel_arg_struct a;
|
|
|
|
if (copy_from_user(&a, arg, sizeof(a)))
|
|
return -EFAULT;
|
|
return do_compat_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp),
|
|
compat_ptr(a.exp), compat_ptr(a.tvp));
|
|
}
|
|
|
|
static long do_compat_pselect(int n, compat_ulong_t __user *inp,
|
|
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
|
|
void __user *tsp, compat_sigset_t __user *sigmask,
|
|
compat_size_t sigsetsize, enum poll_time_type type)
|
|
{
|
|
struct timespec64 ts, end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (tsp) {
|
|
switch (type) {
|
|
case PT_OLD_TIMESPEC:
|
|
if (get_old_timespec32(&ts, tsp))
|
|
return -EFAULT;
|
|
break;
|
|
case PT_TIMESPEC:
|
|
if (get_timespec64(&ts, tsp))
|
|
return -EFAULT;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = set_compat_user_sigmask(sigmask, sigsetsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = compat_core_sys_select(n, inp, outp, exp, to);
|
|
return poll_select_finish(&end_time, tsp, type, ret);
|
|
}
|
|
|
|
struct compat_sigset_argpack {
|
|
compat_uptr_t p;
|
|
compat_size_t size;
|
|
};
|
|
static inline int get_compat_sigset_argpack(struct compat_sigset_argpack *to,
|
|
struct compat_sigset_argpack __user *from)
|
|
{
|
|
if (from) {
|
|
if (!user_read_access_begin(from, sizeof(*from)))
|
|
return -EFAULT;
|
|
unsafe_get_user(to->p, &from->p, Efault);
|
|
unsafe_get_user(to->size, &from->size, Efault);
|
|
user_read_access_end();
|
|
}
|
|
return 0;
|
|
Efault:
|
|
user_access_end();
|
|
return -EFAULT;
|
|
}
|
|
|
|
COMPAT_SYSCALL_DEFINE6(pselect6_time64, int, n, compat_ulong_t __user *, inp,
|
|
compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
|
|
struct __kernel_timespec __user *, tsp, void __user *, sig)
|
|
{
|
|
struct compat_sigset_argpack x = {0, 0};
|
|
|
|
if (get_compat_sigset_argpack(&x, sig))
|
|
return -EFAULT;
|
|
|
|
return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(x.p),
|
|
x.size, PT_TIMESPEC);
|
|
}
|
|
|
|
#if defined(CONFIG_COMPAT_32BIT_TIME)
|
|
|
|
COMPAT_SYSCALL_DEFINE6(pselect6_time32, int, n, compat_ulong_t __user *, inp,
|
|
compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
|
|
struct old_timespec32 __user *, tsp, void __user *, sig)
|
|
{
|
|
struct compat_sigset_argpack x = {0, 0};
|
|
|
|
if (get_compat_sigset_argpack(&x, sig))
|
|
return -EFAULT;
|
|
|
|
return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(x.p),
|
|
x.size, PT_OLD_TIMESPEC);
|
|
}
|
|
|
|
#endif
|
|
|
|
#if defined(CONFIG_COMPAT_32BIT_TIME)
|
|
COMPAT_SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds,
|
|
unsigned int, nfds, struct old_timespec32 __user *, tsp,
|
|
const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize)
|
|
{
|
|
struct timespec64 ts, end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (tsp) {
|
|
if (get_old_timespec32(&ts, tsp))
|
|
return -EFAULT;
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = set_compat_user_sigmask(sigmask, sigsetsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = do_sys_poll(ufds, nfds, to);
|
|
return poll_select_finish(&end_time, tsp, PT_OLD_TIMESPEC, ret);
|
|
}
|
|
#endif
|
|
|
|
/* New compat syscall for 64 bit time_t*/
|
|
COMPAT_SYSCALL_DEFINE5(ppoll_time64, struct pollfd __user *, ufds,
|
|
unsigned int, nfds, struct __kernel_timespec __user *, tsp,
|
|
const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize)
|
|
{
|
|
struct timespec64 ts, end_time, *to = NULL;
|
|
int ret;
|
|
|
|
if (tsp) {
|
|
if (get_timespec64(&ts, tsp))
|
|
return -EFAULT;
|
|
|
|
to = &end_time;
|
|
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = set_compat_user_sigmask(sigmask, sigsetsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = do_sys_poll(ufds, nfds, to);
|
|
return poll_select_finish(&end_time, tsp, PT_TIMESPEC, ret);
|
|
}
|
|
|
|
#endif
|