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fs/select.c
34.6 KB
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// SPDX-License-Identifier: GPL-2.0 |
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/* * This file contains the procedures for the handling of select and poll * * Created for Linux based loosely upon Mathius Lattner's minix * patches by Peter MacDonald. Heavily edited by Linus. * * 4 February 1994 * COFF/ELF binary emulation. If the process has the STICKY_TIMEOUTS * flag set in its personality we do *not* modify the given timeout * parameter to reflect time remaining. * * 24 January 2000 * Changed sys_poll()/do_poll() to use PAGE_SIZE chunk-based allocation * of fds to overcome nfds < 16390 descriptors limit (Tigran Aivazian). */ |
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#include <linux/kernel.h> |
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#include <linux/sched/signal.h> #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> #include <linux/personality.h> /* for STICKY_TIMEOUTS */ #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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|
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#include <linux/uaccess.h> |
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|
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/* * Estimate expected accuracy in ns from a timeval. * * After quite a bit of churning around, we've settled on * a simple thing of taking 0.1% of the timeout as the * slack, with a cap of 100 msec. * "nice" tasks get a 0.5% slack instead. * * Consider this comment an open invitation to come up with even * better solutions.. */ |
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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) 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)) return MAX_SLACK; |
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slack = tv->tv_nsec / divfactor; slack += tv->tv_sec * (NSEC_PER_SEC/divfactor); |
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if (slack > MAX_SLACK) return MAX_SLACK; |
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|
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return slack; } |
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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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/* * Realtime tasks get a slack of 0 for obvious reasons. */ |
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if (rt_task(current)) |
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return 0; |
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ktime_get_ts64(&now); now = timespec64_sub(*tv, now); |
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ret = __estimate_accuracy(&now); if (ret < current->timer_slack_ns) return current->timer_slack_ns; return ret; } |
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struct poll_table_page { struct poll_table_page * next; struct poll_table_entry * entry; struct poll_table_entry entries[0]; }; #define POLL_TABLE_FULL(table) \ ((unsigned long)((table)->entry+1) > PAGE_SIZE + (unsigned long)(table)) /* * Ok, Peter made a complicated, but straightforward multiple_wait() function. * I have rewritten this, taking some shortcuts: This code may not be easy to * follow, but it should be free of race-conditions, and it's practical. If you * understand what I'm doing here, then you understand how the linux * sleep/wakeup mechanism works. * * Two very simple procedures, poll_wait() and poll_freewait() make all the * work. poll_wait() is an inline-function defined in <linux/poll.h>, * as all select/poll functions have to call it to add an entry to the * poll table. */ |
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static void __pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p); |
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void poll_initwait(struct poll_wqueues *pwq) { 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; 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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remove_wait_queue(entry->wait_address, &entry->wait); |
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fput(entry->filp); } |
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void poll_freewait(struct poll_wqueues *pwq) { struct poll_table_page * p = pwq->table; |
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int i; for (i = 0; i < pwq->inline_index; i++) free_poll_entry(pwq->inline_entries + i); |
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while (p) { struct poll_table_entry * entry; struct poll_table_page *old; entry = p->entry; do { entry--; |
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free_poll_entry(entry); |
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} while (entry > p->entries); old = p; p = p->next; free_page((unsigned long) old); } } |
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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) return p->inline_entries + p->inline_index++; |
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if (!table || POLL_TABLE_FULL(table)) { struct poll_table_page *new_table; new_table = (struct poll_table_page *) __get_free_page(GFP_KERNEL); if (!new_table) { p->error = -ENOMEM; |
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return NULL; |
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} new_table->entry = new_table->entries; new_table->next = table; p->table = new_table; table = new_table; } |
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return table->entry++; } |
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static int __pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key) |
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{ struct poll_wqueues *pwq = wait->private; DECLARE_WAITQUEUE(dummy_wait, pwq->polling_task); /* * Although this function is called under waitqueue lock, LOCK * doesn't imply write barrier and the users expect write * barrier semantics on wakeup functions. The following * 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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*/ smp_wmb(); pwq->triggered = 1; /* * Perform the default wake up operation using a dummy * waitqueue. * * TODO: This is hacky but there currently is no interface to * pass in @sync. @sync is scheduled to be removed and once * that happens, wake_up_process() can be used directly. */ return default_wake_function(&dummy_wait, mode, sync, key); } |
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static int pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key) |
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{ struct poll_table_entry *entry; 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; return __pollwake(wait, mode, sync, key); } |
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/* Add a new entry */ static void __pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) { |
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struct poll_wqueues *pwq = container_of(p, struct poll_wqueues, pt); struct poll_table_entry *entry = poll_get_entry(pwq); |
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if (!entry) 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); 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) { int rc = -EINTR; set_current_state(state); 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); /* * Prepare for the next iteration. * |
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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 * written before wake up is always visible after wake up. * Second, the full barrier guarantees that triggered clearing * doesn't pass event check of the next iteration. Note that * this problem doesn't exist for the first iteration as * add_wait_queue() has full barrier semantics. */ |
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smp_store_mb(pwq->triggered, 0); |
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return rc; } |
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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) * @nsec: nanoseconds (from user space) * * Note, we do not use a timespec for the user space value here, That * way we can use the function for timeval and compat interfaces as well. * * Returns -EINVAL if sec/nsec are not normalized. Otherwise 0. */ |
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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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|
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if (!timespec64_valid(&ts)) |
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return -EINVAL; /* Optimize for the zero timeout value here */ if (!sec && !nsec) { to->tv_sec = to->tv_nsec = 0; } else { |
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ktime_get_ts64(to); *to = timespec64_add_safe(*to, ts); |
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} return 0; } |
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static int poll_select_copy_remaining(struct timespec64 *end_time, void __user *p, |
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int timeval, int ret) { |
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struct timespec64 rts; |
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struct timeval rtv; if (!p) return ret; if (current->personality & STICKY_TIMEOUTS) goto sticky; /* No update for zero timeout */ if (!end_time->tv_sec && !end_time->tv_nsec) return ret; |
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ktime_get_ts64(&rts); rts = timespec64_sub(*end_time, rts); if (rts.tv_sec < 0) rts.tv_sec = rts.tv_nsec = 0; |
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|
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if (timeval) { |
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if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec)) memset(&rtv, 0, sizeof(rtv)); |
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rtv.tv_sec = rts.tv_sec; rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC; |
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if (!copy_to_user(p, &rtv, sizeof(rtv))) return ret; |
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} else if (!put_timespec64(&rts, p)) |
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return ret; /* * If an application puts its timeval in read-only memory, we * don't want the Linux-specific update to the timeval to * cause a fault after the select has completed * successfully. However, because we're not updating the * timeval, we can't restart the system call. */ sticky: if (ret == -ERESTARTNOHAND) ret = -EINTR; return ret; } |
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/* * Scalable version of the fd_set. */ typedef struct { unsigned long *in, *out, *ex; unsigned long *res_in, *res_out, *res_ex; } fd_set_bits; /* * How many longwords for "nr" bits? */ #define FDS_BITPERLONG (8*sizeof(long)) #define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG) #define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long)) /* * We do a VERIFY_WRITE here even though we are only reading this time: * we'll write to it eventually.. * * Use "unsigned long" accesses to let user-mode fd_set's be long-aligned. */ static inline int get_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset) { nr = FDS_BYTES(nr); if (ufdset) return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0; memset(fdset, 0, nr); return 0; } static inline unsigned long __must_check set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset) { if (ufdset) return __copy_to_user(ufdset, fdset, FDS_BYTES(nr)); return 0; } static inline void zero_fd_set(unsigned long nr, unsigned long *fdset) { memset(fdset, 0, FDS_BYTES(nr)); } |
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#define FDS_IN(fds, n) (fds->in + n) #define FDS_OUT(fds, n) (fds->out + n) #define FDS_EX(fds, n) (fds->ex + n) #define BITS(fds, n) (*FDS_IN(fds, n)|*FDS_OUT(fds, n)|*FDS_EX(fds, n)) static int max_select_fd(unsigned long n, fd_set_bits *fds) { unsigned long *open_fds; unsigned long set; int max; |
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struct fdtable *fdt; |
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/* handle last in-complete long-word first */ |
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set = ~(~0UL << (n & (BITS_PER_LONG-1))); 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; if (set) { set &= BITS(fds, n); if (set) { if (!(set & ~*open_fds)) goto get_max; return -EBADF; } } while (n) { open_fds--; n--; set = BITS(fds, n); if (!set) continue; if (set & ~*open_fds) return -EBADF; if (max) continue; get_max: do { max++; set >>= 1; } while (set); |
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max += n * BITS_PER_LONG; |
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} return max; } |
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#define POLLIN_SET (EPOLLRDNORM | EPOLLRDBAND | EPOLLIN | EPOLLHUP | EPOLLERR) #define POLLOUT_SET (EPOLLWRBAND | EPOLLWRNORM | EPOLLOUT | EPOLLERR) #define POLLEX_SET (EPOLLPRI) |
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|
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static inline void wait_key_set(poll_table *wait, unsigned long in, |
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unsigned long out, unsigned long bit, |
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__poll_t ll_flag) |
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{ |
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wait->_key = POLLEX_SET | ll_flag; |
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if (in & bit) wait->_key |= POLLIN_SET; if (out & bit) wait->_key |= POLLOUT_SET; |
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} |
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static int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time) |
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{ |
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ktime_t expire, *to = NULL; |
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struct poll_wqueues table; poll_table *wait; |
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int retval, i, timed_out = 0; |
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u64 slack = 0; |
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__poll_t busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0; |
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unsigned long busy_start = 0; |
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|
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rcu_read_lock(); |
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retval = max_select_fd(n, fds); |
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rcu_read_unlock(); |
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if (retval < 0) return retval; n = retval; poll_initwait(&table); wait = &table.pt; |
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if (end_time && !end_time->tv_sec && !end_time->tv_nsec) { |
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wait->_qproc = NULL; |
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timed_out = 1; } |
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if (end_time && !timed_out) |
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slack = select_estimate_accuracy(end_time); |
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|
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retval = 0; for (;;) { unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp; |
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bool can_busy_loop = false; |
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|
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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) { |
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unsigned long in, out, ex, all_bits, bit = 1, j; |
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unsigned long res_in = 0, res_out = 0, res_ex = 0; |
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__poll_t mask; |
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in = *inp++; out = *outp++; ex = *exp++; all_bits = in | out | ex; if (all_bits == 0) { |
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i += BITS_PER_LONG; |
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continue; } |
8ded2bbc1 posix_types.h: Cl... |
464 |
for (j = 0; j < BITS_PER_LONG; ++j, ++i, bit <<= 1) { |
2903ff019 switch simple cas... |
465 |
struct fd f; |
1da177e4c Linux-2.6.12-rc2 |
466 467 468 469 |
if (i >= n) break; if (!(bit & all_bits)) continue; |
2903ff019 switch simple cas... |
470 471 |
f = fdget(i); if (f.file) { |
9965ed174 fs: add new vfs_p... |
472 473 474 |
wait_key_set(wait, in, out, bit, busy_flag); mask = vfs_poll(f.file, wait); |
2903ff019 switch simple cas... |
475 |
fdput(f); |
1da177e4c Linux-2.6.12-rc2 |
476 477 478 |
if ((mask & POLLIN_SET) && (in & bit)) { res_in |= bit; retval++; |
626cf2366 poll: add poll_re... |
479 |
wait->_qproc = NULL; |
1da177e4c Linux-2.6.12-rc2 |
480 481 482 483 |
} if ((mask & POLLOUT_SET) && (out & bit)) { res_out |= bit; retval++; |
626cf2366 poll: add poll_re... |
484 |
wait->_qproc = NULL; |
1da177e4c Linux-2.6.12-rc2 |
485 486 487 488 |
} if ((mask & POLLEX_SET) && (ex & bit)) { res_ex |= bit; retval++; |
626cf2366 poll: add poll_re... |
489 |
wait->_qproc = NULL; |
1da177e4c Linux-2.6.12-rc2 |
490 |
} |
2d48d67fa net: poll/select ... |
491 |
/* got something, stop busy polling */ |
cbf55001b net: rename low l... |
492 493 494 495 496 497 498 499 500 501 |
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; |
1da177e4c Linux-2.6.12-rc2 |
502 |
} |
1da177e4c Linux-2.6.12-rc2 |
503 504 505 506 507 508 509 |
} if (res_in) *rinp = res_in; if (res_out) *routp = res_out; if (res_ex) *rexp = res_ex; |
55d853849 Fix performance r... |
510 |
cond_resched(); |
1da177e4c Linux-2.6.12-rc2 |
511 |
} |
626cf2366 poll: add poll_re... |
512 |
wait->_qproc = NULL; |
8ff3e8e85 select: switch se... |
513 |
if (retval || timed_out || signal_pending(current)) |
1da177e4c Linux-2.6.12-rc2 |
514 |
break; |
f5264481c trivial: small cl... |
515 |
if (table.error) { |
1da177e4c Linux-2.6.12-rc2 |
516 517 518 |
retval = table.error; break; } |
9f72949f6 [PATCH] Add psele... |
519 |
|
cbf55001b net: rename low l... |
520 |
/* only if found POLL_BUSY_LOOP sockets && not out of time */ |
76b1e9b98 net/fs: change bu... |
521 |
if (can_busy_loop && !need_resched()) { |
37056719b net: Track start ... |
522 523 |
if (!busy_start) { busy_start = busy_loop_current_time(); |
76b1e9b98 net/fs: change bu... |
524 525 |
continue; } |
37056719b net: Track start ... |
526 |
if (!busy_loop_timeout(busy_start)) |
76b1e9b98 net/fs: change bu... |
527 528 529 |
continue; } busy_flag = 0; |
2d48d67fa net: poll/select ... |
530 |
|
8ff3e8e85 select: switch se... |
531 532 533 534 535 536 |
/* * 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) { |
766b9f928 fs: poll/select/r... |
537 |
expire = timespec64_to_ktime(*end_time); |
8ff3e8e85 select: switch se... |
538 |
to = &expire; |
9f72949f6 [PATCH] Add psele... |
539 |
} |
8ff3e8e85 select: switch se... |
540 |
|
5f820f648 poll: allow f_op-... |
541 542 |
if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE, to, slack)) |
8ff3e8e85 select: switch se... |
543 |
timed_out = 1; |
1da177e4c Linux-2.6.12-rc2 |
544 |
} |
1da177e4c Linux-2.6.12-rc2 |
545 546 |
poll_freewait(&table); |
1da177e4c Linux-2.6.12-rc2 |
547 548 |
return retval; } |
1da177e4c Linux-2.6.12-rc2 |
549 550 551 552 553 554 555 556 |
/* * 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. */ |
a2dcb44c3 [PATCH] make osf_... |
557 |
int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, |
766b9f928 fs: poll/select/r... |
558 |
fd_set __user *exp, struct timespec64 *end_time) |
1da177e4c Linux-2.6.12-rc2 |
559 560 |
{ fd_set_bits fds; |
29ff2db55 [PATCH] select() ... |
561 |
void *bits; |
bbea9f696 [PATCH] fdtable: ... |
562 |
int ret, max_fds; |
2d19309cf fs/select: add vm... |
563 |
size_t size, alloc_size; |
badf16621 [PATCH] files: br... |
564 |
struct fdtable *fdt; |
70674f95c [PATCH] Optimize ... |
565 |
/* Allocate small arguments on the stack to save memory and be faster */ |
30c14e40e [PATCH] avoid una... |
566 |
long stack_fds[SELECT_STACK_ALLOC/sizeof(long)]; |
1da177e4c Linux-2.6.12-rc2 |
567 |
|
1da177e4c Linux-2.6.12-rc2 |
568 569 570 |
ret = -EINVAL; if (n < 0) goto out_nofds; |
bbea9f696 [PATCH] fdtable: ... |
571 |
/* max_fds can increase, so grab it once to avoid race */ |
b835996f6 [PATCH] files: lo... |
572 |
rcu_read_lock(); |
badf16621 [PATCH] files: br... |
573 |
fdt = files_fdtable(current->files); |
bbea9f696 [PATCH] fdtable: ... |
574 |
max_fds = fdt->max_fds; |
b835996f6 [PATCH] files: lo... |
575 |
rcu_read_unlock(); |
bbea9f696 [PATCH] fdtable: ... |
576 577 |
if (n > max_fds) n = max_fds; |
1da177e4c Linux-2.6.12-rc2 |
578 579 580 581 582 583 |
/* * 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. */ |
1da177e4c Linux-2.6.12-rc2 |
584 |
size = FDS_BYTES(n); |
b04eb6aa0 [PATCH] select: d... |
585 586 587 588 |
bits = stack_fds; if (size > sizeof(stack_fds) / 6) { /* Not enough space in on-stack array; must use kmalloc */ ret = -ENOMEM; |
2d19309cf fs/select: add vm... |
589 590 591 592 |
if (size > (SIZE_MAX / 6)) goto out_nofds; alloc_size = 6 * size; |
752ade68c treewide: use kv[... |
593 |
bits = kvmalloc(alloc_size, GFP_KERNEL); |
b04eb6aa0 [PATCH] select: d... |
594 595 596 |
if (!bits) goto out_nofds; } |
29ff2db55 [PATCH] select() ... |
597 598 599 600 601 602 |
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; |
1da177e4c Linux-2.6.12-rc2 |
603 604 605 606 607 608 609 610 |
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); |
8ff3e8e85 select: switch se... |
611 |
ret = do_select(n, &fds, end_time); |
1da177e4c Linux-2.6.12-rc2 |
612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 |
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: |
70674f95c [PATCH] Optimize ... |
628 |
if (bits != stack_fds) |
2d19309cf fs/select: add vm... |
629 |
kvfree(bits); |
1da177e4c Linux-2.6.12-rc2 |
630 631 632 |
out_nofds: return ret; } |
4bdb9acab fs: add kern_sele... |
633 634 |
static int kern_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp) |
9f72949f6 [PATCH] Add psele... |
635 |
{ |
766b9f928 fs: poll/select/r... |
636 |
struct timespec64 end_time, *to = NULL; |
9f72949f6 [PATCH] Add psele... |
637 638 639 640 641 642 |
struct timeval tv; int ret; if (tvp) { if (copy_from_user(&tv, tvp, sizeof(tv))) return -EFAULT; |
8ff3e8e85 select: switch se... |
643 |
to = &end_time; |
4d36a9e65 select: deal with... |
644 645 646 |
if (poll_select_set_timeout(to, tv.tv_sec + (tv.tv_usec / USEC_PER_SEC), (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC)) |
9f72949f6 [PATCH] Add psele... |
647 |
return -EINVAL; |
9f72949f6 [PATCH] Add psele... |
648 |
} |
8ff3e8e85 select: switch se... |
649 650 |
ret = core_sys_select(n, inp, outp, exp, to); ret = poll_select_copy_remaining(&end_time, tvp, 1, ret); |
9f72949f6 [PATCH] Add psele... |
651 652 653 |
return ret; } |
4bdb9acab fs: add kern_sele... |
654 655 656 657 658 |
SYSCALL_DEFINE5(select, int, n, fd_set __user *, inp, fd_set __user *, outp, fd_set __user *, exp, struct timeval __user *, tvp) { return kern_select(n, inp, outp, exp, tvp); } |
c9da9f212 [CVE-2009-0029] M... |
659 660 661 |
static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timespec __user *tsp, const sigset_t __user *sigmask, size_t sigsetsize) |
9f72949f6 [PATCH] Add psele... |
662 |
{ |
9f72949f6 [PATCH] Add psele... |
663 |
sigset_t ksigmask, sigsaved; |
36819ad09 select: Use get/p... |
664 |
struct timespec64 ts, end_time, *to = NULL; |
9f72949f6 [PATCH] Add psele... |
665 666 667 |
int ret; if (tsp) { |
36819ad09 select: Use get/p... |
668 |
if (get_timespec64(&ts, tsp)) |
9f72949f6 [PATCH] Add psele... |
669 |
return -EFAULT; |
8ff3e8e85 select: switch se... |
670 |
to = &end_time; |
36819ad09 select: Use get/p... |
671 |
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec)) |
9f72949f6 [PATCH] Add psele... |
672 |
return -EINVAL; |
9f72949f6 [PATCH] Add psele... |
673 674 675 676 677 678 679 680 681 682 683 684 |
} if (sigmask) { /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) return -EFAULT; sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); } |
62568510b Fix timeouts in s... |
685 |
ret = core_sys_select(n, inp, outp, exp, to); |
8ff3e8e85 select: switch se... |
686 |
ret = poll_select_copy_remaining(&end_time, tsp, 0, ret); |
9f72949f6 [PATCH] Add psele... |
687 688 689 690 691 692 693 694 695 696 |
if (ret == -ERESTARTNOHAND) { /* * Don't restore the signal mask yet. Let do_signal() deliver * the signal on the way back to userspace, before the signal * mask is restored. */ if (sigmask) { memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); |
4e4c22c71 signals: add set_... |
697 |
set_restore_sigmask(); |
9f72949f6 [PATCH] Add psele... |
698 699 700 701 702 703 704 705 706 707 708 709 710 |
} } else if (sigmask) sigprocmask(SIG_SETMASK, &sigsaved, NULL); return 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. */ |
d4e82042c [CVE-2009-0029] S... |
711 712 713 |
SYSCALL_DEFINE6(pselect6, int, n, fd_set __user *, inp, fd_set __user *, outp, fd_set __user *, exp, struct timespec __user *, tsp, void __user *, sig) |
9f72949f6 [PATCH] Add psele... |
714 715 716 717 718 719 |
{ size_t sigsetsize = 0; sigset_t __user *up = NULL; if (sig) { if (!access_ok(VERIFY_READ, sig, sizeof(void *)+sizeof(size_t)) |
e110ab94e [PATCH] fix __use... |
720 |
|| __get_user(up, (sigset_t __user * __user *)sig) |
9f72949f6 [PATCH] Add psele... |
721 |
|| __get_user(sigsetsize, |
e110ab94e [PATCH] fix __use... |
722 |
(size_t __user *)(sig+sizeof(void *)))) |
9f72949f6 [PATCH] Add psele... |
723 724 |
return -EFAULT; } |
c9da9f212 [CVE-2009-0029] M... |
725 |
return do_pselect(n, inp, outp, exp, tsp, up, sigsetsize); |
9f72949f6 [PATCH] Add psele... |
726 |
} |
9f72949f6 [PATCH] Add psele... |
727 |
|
5d0e52830 Add generic sys_o... |
728 729 730 731 732 733 734 735 736 737 738 739 740 |
#ifdef __ARCH_WANT_SYS_OLD_SELECT struct sel_arg_struct { unsigned long n; fd_set __user *inp, *outp, *exp; struct 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; |
4bdb9acab fs: add kern_sele... |
741 |
return kern_select(a.n, a.inp, a.outp, a.exp, a.tvp); |
5d0e52830 Add generic sys_o... |
742 743 |
} #endif |
1da177e4c Linux-2.6.12-rc2 |
744 745 746 747 748 749 750 |
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)) |
4a4b69f79 [PATCH] Poll clea... |
751 752 753 754 755 |
/* * 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, |
626cf2366 poll: add poll_re... |
756 |
* if pwait->_qproc is non-NULL. |
4a4b69f79 [PATCH] Poll clea... |
757 |
*/ |
fb3679372 annotate poll(2) ... |
758 |
static inline __poll_t do_pollfd(struct pollfd *pollfd, poll_table *pwait, |
cbf55001b net: rename low l... |
759 |
bool *can_busy_poll, |
fb3679372 annotate poll(2) ... |
760 |
__poll_t busy_flag) |
1da177e4c Linux-2.6.12-rc2 |
761 |
{ |
a0f8dcfc6 fs: cleanup do_po... |
762 763 764 765 766 767 768 769 770 771 772 773 774 |
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; |
9965ed174 fs: add new vfs_p... |
775 776 777 778 |
pwait->_key = filter | busy_flag; mask = vfs_poll(f.file, pwait); if (mask & busy_flag) *can_busy_poll = true; |
a0f8dcfc6 fs: cleanup do_po... |
779 780 781 782 |
mask &= filter; /* Mask out unneeded events. */ fdput(f); out: |
fb3679372 annotate poll(2) ... |
783 |
/* ... and so does ->revents */ |
c71d227fc make kernel-side ... |
784 |
pollfd->revents = mangle_poll(mask); |
4a4b69f79 [PATCH] Poll clea... |
785 |
return mask; |
1da177e4c Linux-2.6.12-rc2 |
786 |
} |
ccec5ee30 poll: plug an unu... |
787 |
static int do_poll(struct poll_list *list, struct poll_wqueues *wait, |
766b9f928 fs: poll/select/r... |
788 |
struct timespec64 *end_time) |
1da177e4c Linux-2.6.12-rc2 |
789 |
{ |
1da177e4c Linux-2.6.12-rc2 |
790 |
poll_table* pt = &wait->pt; |
8ff3e8e85 select: switch se... |
791 792 |
ktime_t expire, *to = NULL; int timed_out = 0, count = 0; |
da8b44d5a timer: convert ti... |
793 |
u64 slack = 0; |
fb3679372 annotate poll(2) ... |
794 |
__poll_t busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0; |
37056719b net: Track start ... |
795 |
unsigned long busy_start = 0; |
1da177e4c Linux-2.6.12-rc2 |
796 |
|
9f72949f6 [PATCH] Add psele... |
797 |
/* Optimise the no-wait case */ |
8ff3e8e85 select: switch se... |
798 |
if (end_time && !end_time->tv_sec && !end_time->tv_nsec) { |
626cf2366 poll: add poll_re... |
799 |
pt->_qproc = NULL; |
8ff3e8e85 select: switch se... |
800 801 |
timed_out = 1; } |
9bf084f70 do_poll: return -... |
802 |
|
96d2ab484 hrtimer: fix sign... |
803 |
if (end_time && !timed_out) |
231f3d393 select: rename es... |
804 |
slack = select_estimate_accuracy(end_time); |
90d6e24a3 hrtimer: make sel... |
805 |
|
1da177e4c Linux-2.6.12-rc2 |
806 807 |
for (;;) { struct poll_list *walk; |
cbf55001b net: rename low l... |
808 |
bool can_busy_loop = false; |
9f72949f6 [PATCH] Add psele... |
809 |
|
4a4b69f79 [PATCH] Poll clea... |
810 811 812 813 814 815 816 817 |
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 |
626cf2366 poll: add poll_re... |
818 |
* and kill poll_table->_qproc, so we don't |
4a4b69f79 [PATCH] Poll clea... |
819 820 821 822 |
* needlessly register any other waiters after * this. They'll get immediately deregistered * when we break out and return. */ |
cbf55001b net: rename low l... |
823 824 |
if (do_pollfd(pfd, pt, &can_busy_loop, busy_flag)) { |
4a4b69f79 [PATCH] Poll clea... |
825 |
count++; |
626cf2366 poll: add poll_re... |
826 |
pt->_qproc = NULL; |
cbf55001b net: rename low l... |
827 828 829 |
/* found something, stop busy polling */ busy_flag = 0; can_busy_loop = false; |
4a4b69f79 [PATCH] Poll clea... |
830 831 |
} } |
1da177e4c Linux-2.6.12-rc2 |
832 |
} |
4a4b69f79 [PATCH] Poll clea... |
833 834 |
/* * All waiters have already been registered, so don't provide |
626cf2366 poll: add poll_re... |
835 |
* a poll_table->_qproc to them on the next loop iteration. |
4a4b69f79 [PATCH] Poll clea... |
836 |
*/ |
626cf2366 poll: add poll_re... |
837 |
pt->_qproc = NULL; |
9bf084f70 do_poll: return -... |
838 839 840 841 842 |
if (!count) { count = wait->error; if (signal_pending(current)) count = -EINTR; } |
8ff3e8e85 select: switch se... |
843 |
if (count || timed_out) |
1da177e4c Linux-2.6.12-rc2 |
844 |
break; |
9f72949f6 [PATCH] Add psele... |
845 |
|
cbf55001b net: rename low l... |
846 |
/* only if found POLL_BUSY_LOOP sockets && not out of time */ |
76b1e9b98 net/fs: change bu... |
847 |
if (can_busy_loop && !need_resched()) { |
37056719b net: Track start ... |
848 849 |
if (!busy_start) { busy_start = busy_loop_current_time(); |
76b1e9b98 net/fs: change bu... |
850 851 |
continue; } |
37056719b net: Track start ... |
852 |
if (!busy_loop_timeout(busy_start)) |
76b1e9b98 net/fs: change bu... |
853 854 855 |
continue; } busy_flag = 0; |
91e2fd337 net: avoid callin... |
856 |
|
8ff3e8e85 select: switch se... |
857 858 859 860 861 862 |
/* * 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) { |
766b9f928 fs: poll/select/r... |
863 |
expire = timespec64_to_ktime(*end_time); |
8ff3e8e85 select: switch se... |
864 |
to = &expire; |
9f72949f6 [PATCH] Add psele... |
865 |
} |
5f820f648 poll: allow f_op-... |
866 |
if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE, to, slack)) |
8ff3e8e85 select: switch se... |
867 |
timed_out = 1; |
1da177e4c Linux-2.6.12-rc2 |
868 |
} |
1da177e4c Linux-2.6.12-rc2 |
869 870 |
return count; } |
70674f95c [PATCH] Optimize ... |
871 872 |
#define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \ sizeof(struct pollfd)) |
e99ca56ce move compat selec... |
873 |
static int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, |
766b9f928 fs: poll/select/r... |
874 |
struct timespec64 *end_time) |
1da177e4c Linux-2.6.12-rc2 |
875 876 |
{ struct poll_wqueues table; |
252e5725c do_sys_poll: simp... |
877 |
int err = -EFAULT, fdcount, len, size; |
30c14e40e [PATCH] avoid una... |
878 879 880 881 |
/* 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)]; |
252e5725c do_sys_poll: simp... |
882 883 884 |
struct poll_list *const head = (struct poll_list *)stack_pps; struct poll_list *walk = head; unsigned long todo = nfds; |
1da177e4c Linux-2.6.12-rc2 |
885 |
|
d554ed895 fs: use rlimit he... |
886 |
if (nfds > rlimit(RLIMIT_NOFILE)) |
1da177e4c Linux-2.6.12-rc2 |
887 |
return -EINVAL; |
252e5725c do_sys_poll: simp... |
888 889 890 891 892 893 |
len = min_t(unsigned int, nfds, N_STACK_PPS); for (;;) { walk->next = NULL; walk->len = len; if (!len) break; |
1da177e4c Linux-2.6.12-rc2 |
894 |
|
252e5725c do_sys_poll: simp... |
895 896 897 898 899 900 901 |
if (copy_from_user(walk->entries, ufds + nfds-todo, sizeof(struct pollfd) * walk->len)) goto out_fds; todo -= walk->len; if (!todo) break; |
1da177e4c Linux-2.6.12-rc2 |
902 |
|
252e5725c do_sys_poll: simp... |
903 904 905 906 907 |
len = min(todo, POLLFD_PER_PAGE); size = sizeof(struct poll_list) + sizeof(struct pollfd) * len; walk = walk->next = kmalloc(size, GFP_KERNEL); if (!walk) { err = -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
908 909 |
goto out_fds; } |
1da177e4c Linux-2.6.12-rc2 |
910 |
} |
9f72949f6 [PATCH] Add psele... |
911 |
|
252e5725c do_sys_poll: simp... |
912 |
poll_initwait(&table); |
ccec5ee30 poll: plug an unu... |
913 |
fdcount = do_poll(head, &table, end_time); |
252e5725c do_sys_poll: simp... |
914 |
poll_freewait(&table); |
1da177e4c Linux-2.6.12-rc2 |
915 |
|
252e5725c do_sys_poll: simp... |
916 |
for (walk = head; walk; walk = walk->next) { |
1da177e4c Linux-2.6.12-rc2 |
917 918 |
struct pollfd *fds = walk->entries; int j; |
252e5725c do_sys_poll: simp... |
919 920 |
for (j = 0; j < walk->len; j++, ufds++) if (__put_user(fds[j].revents, &ufds->revents)) |
1da177e4c Linux-2.6.12-rc2 |
921 |
goto out_fds; |
1da177e4c Linux-2.6.12-rc2 |
922 |
} |
252e5725c do_sys_poll: simp... |
923 |
|
1da177e4c Linux-2.6.12-rc2 |
924 |
err = fdcount; |
1da177e4c Linux-2.6.12-rc2 |
925 |
out_fds: |
252e5725c do_sys_poll: simp... |
926 927 928 929 930 |
walk = head->next; while (walk) { struct poll_list *pos = walk; walk = walk->next; kfree(pos); |
1da177e4c Linux-2.6.12-rc2 |
931 |
} |
252e5725c do_sys_poll: simp... |
932 |
|
1da177e4c Linux-2.6.12-rc2 |
933 934 |
return err; } |
9f72949f6 [PATCH] Add psele... |
935 |
|
3075d9da0 Use ERESTART_REST... |
936 937 |
static long do_restart_poll(struct restart_block *restart_block) { |
8ff3e8e85 select: switch se... |
938 939 |
struct pollfd __user *ufds = restart_block->poll.ufds; int nfds = restart_block->poll.nfds; |
766b9f928 fs: poll/select/r... |
940 |
struct timespec64 *to = NULL, end_time; |
3075d9da0 Use ERESTART_REST... |
941 |
int ret; |
8ff3e8e85 select: switch se... |
942 943 944 945 946 947 948 |
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); |
3075d9da0 Use ERESTART_REST... |
949 950 |
if (ret == -EINTR) { restart_block->fn = do_restart_poll; |
3075d9da0 Use ERESTART_REST... |
951 952 953 954 |
ret = -ERESTART_RESTARTBLOCK; } return ret; } |
5a8a82b1d [CVE-2009-0029] S... |
955 |
SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds, |
faf309009 sys_poll: fix inc... |
956 |
int, timeout_msecs) |
9f72949f6 [PATCH] Add psele... |
957 |
{ |
766b9f928 fs: poll/select/r... |
958 |
struct timespec64 end_time, *to = NULL; |
3075d9da0 Use ERESTART_REST... |
959 |
int ret; |
9f72949f6 [PATCH] Add psele... |
960 |
|
8ff3e8e85 select: switch se... |
961 962 963 964 |
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)); |
9f72949f6 [PATCH] Add psele... |
965 |
} |
8ff3e8e85 select: switch se... |
966 |
ret = do_sys_poll(ufds, nfds, to); |
3075d9da0 Use ERESTART_REST... |
967 968 |
if (ret == -EINTR) { struct restart_block *restart_block; |
8ff3e8e85 select: switch se... |
969 |
|
f56141e3e all arches, signa... |
970 |
restart_block = ¤t->restart_block; |
3075d9da0 Use ERESTART_REST... |
971 |
restart_block->fn = do_restart_poll; |
8ff3e8e85 select: switch se... |
972 973 974 975 976 977 978 979 980 |
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; |
3075d9da0 Use ERESTART_REST... |
981 982 983 |
ret = -ERESTART_RESTARTBLOCK; } return ret; |
9f72949f6 [PATCH] Add psele... |
984 |
} |
d4e82042c [CVE-2009-0029] S... |
985 986 987 |
SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds, struct timespec __user *, tsp, const sigset_t __user *, sigmask, size_t, sigsetsize) |
9f72949f6 [PATCH] Add psele... |
988 989 |
{ sigset_t ksigmask, sigsaved; |
36819ad09 select: Use get/p... |
990 |
struct timespec64 ts, end_time, *to = NULL; |
9f72949f6 [PATCH] Add psele... |
991 992 993 |
int ret; if (tsp) { |
36819ad09 select: Use get/p... |
994 |
if (get_timespec64(&ts, tsp)) |
9f72949f6 [PATCH] Add psele... |
995 |
return -EFAULT; |
8ff3e8e85 select: switch se... |
996 997 998 |
to = &end_time; if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec)) return -EINVAL; |
9f72949f6 [PATCH] Add psele... |
999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 |
} if (sigmask) { /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) return -EFAULT; sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); } |
8ff3e8e85 select: switch se... |
1011 |
ret = do_sys_poll(ufds, nfds, to); |
9f72949f6 [PATCH] Add psele... |
1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 |
/* We can restart this syscall, usually */ if (ret == -EINTR) { /* * Don't restore the signal mask yet. Let do_signal() deliver * the signal on the way back to userspace, before the signal * mask is restored. */ if (sigmask) { memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); |
4e4c22c71 signals: add set_... |
1023 |
set_restore_sigmask(); |
9f72949f6 [PATCH] Add psele... |
1024 1025 1026 1027 |
} ret = -ERESTARTNOHAND; } else if (sigmask) sigprocmask(SIG_SETMASK, &sigsaved, NULL); |
8ff3e8e85 select: switch se... |
1028 |
ret = poll_select_copy_remaining(&end_time, tsp, 0, ret); |
9f72949f6 [PATCH] Add psele... |
1029 1030 1031 |
return ret; } |
e99ca56ce move compat selec... |
1032 1033 1034 1035 1036 |
#ifdef CONFIG_COMPAT #define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t)) static |
36819ad09 select: Use get/p... |
1037 |
int compat_poll_select_copy_remaining(struct timespec64 *end_time, void __user *p, |
e99ca56ce move compat selec... |
1038 1039 |
int timeval, int ret) { |
36819ad09 select: Use get/p... |
1040 |
struct timespec64 ts; |
e99ca56ce move compat selec... |
1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 |
if (!p) return ret; if (current->personality & STICKY_TIMEOUTS) goto sticky; /* No update for zero timeout */ if (!end_time->tv_sec && !end_time->tv_nsec) return ret; |
36819ad09 select: Use get/p... |
1051 1052 |
ktime_get_ts64(&ts); ts = timespec64_sub(*end_time, ts); |
e99ca56ce move compat selec... |
1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 |
if (ts.tv_sec < 0) ts.tv_sec = ts.tv_nsec = 0; if (timeval) { struct compat_timeval rtv; rtv.tv_sec = ts.tv_sec; rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC; if (!copy_to_user(p, &rtv, sizeof(rtv))) return ret; } else { |
36819ad09 select: Use get/p... |
1065 |
if (!compat_put_timespec64(&ts, p)) |
e99ca56ce move compat selec... |
1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 |
return ret; } /* * If an application puts its timeval in read-only memory, we * don't want the Linux-specific update to the timeval to * cause a fault after the select has completed * successfully. However, because we're not updating the * timeval, we can't restart the system call. */ sticky: if (ret == -ERESTARTNOHAND) ret = -EINTR; return ret; } /* * 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) { |
e99ca56ce move compat selec... |
1090 |
if (ufdset) { |
464d62421 select: switch co... |
1091 |
return compat_get_bitmap(fdset, ufdset, nr); |
e99ca56ce move compat selec... |
1092 |
} else { |
79de3cbe9 fs/select: Fix me... |
1093 |
zero_fd_set(nr, fdset); |
464d62421 select: switch co... |
1094 |
return 0; |
e99ca56ce move compat selec... |
1095 |
} |
e99ca56ce move compat selec... |
1096 1097 1098 1099 1100 1101 |
} static int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset, unsigned long *fdset) { |
e99ca56ce move compat selec... |
1102 1103 |
if (!ufdset) return 0; |
464d62421 select: switch co... |
1104 |
return compat_put_bitmap(ufdset, fdset, nr); |
e99ca56ce move compat selec... |
1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 |
} /* * 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, |
36819ad09 select: Use get/p... |
1123 |
struct timespec64 *end_time) |
e99ca56ce move compat selec... |
1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 |
{ 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) { |
6da2ec560 treewide: kmalloc... |
1150 |
bits = kmalloc_array(6, size, GFP_KERNEL); |
e99ca56ce move compat selec... |
1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 |
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; } |
05585e449 fs: add do_compat... |
1191 1192 1193 |
static int do_compat_select(int n, compat_ulong_t __user *inp, compat_ulong_t __user *outp, compat_ulong_t __user *exp, struct compat_timeval __user *tvp) |
e99ca56ce move compat selec... |
1194 |
{ |
36819ad09 select: Use get/p... |
1195 |
struct timespec64 end_time, *to = NULL; |
e99ca56ce move compat selec... |
1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 |
struct compat_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 = compat_core_sys_select(n, inp, outp, exp, to); ret = compat_poll_select_copy_remaining(&end_time, tvp, 1, ret); return ret; } |
05585e449 fs: add do_compat... |
1215 1216 1217 1218 1219 1220 |
COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp, compat_ulong_t __user *, outp, compat_ulong_t __user *, exp, struct compat_timeval __user *, tvp) { return do_compat_select(n, inp, outp, exp, tvp); } |
e99ca56ce move compat selec... |
1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 |
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; |
05585e449 fs: add do_compat... |
1235 1236 |
return do_compat_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp), compat_ptr(a.exp), compat_ptr(a.tvp)); |
e99ca56ce move compat selec... |
1237 1238 1239 1240 1241 1242 1243 |
} static long do_compat_pselect(int n, compat_ulong_t __user *inp, compat_ulong_t __user *outp, compat_ulong_t __user *exp, struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask, compat_size_t sigsetsize) { |
e99ca56ce move compat selec... |
1244 |
sigset_t ksigmask, sigsaved; |
36819ad09 select: Use get/p... |
1245 |
struct timespec64 ts, end_time, *to = NULL; |
e99ca56ce move compat selec... |
1246 1247 1248 |
int ret; if (tsp) { |
36819ad09 select: Use get/p... |
1249 |
if (compat_get_timespec64(&ts, tsp)) |
e99ca56ce move compat selec... |
1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 |
return -EFAULT; to = &end_time; if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec)) return -EINVAL; } if (sigmask) { if (sigsetsize != sizeof(compat_sigset_t)) return -EINVAL; |
3968cf623 get_compat_sigset() |
1260 |
if (get_compat_sigset(&ksigmask, sigmask)) |
e99ca56ce move compat selec... |
1261 |
return -EFAULT; |
e99ca56ce move compat selec... |
1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 |
sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); } ret = compat_core_sys_select(n, inp, outp, exp, to); ret = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret); if (ret == -ERESTARTNOHAND) { /* * Don't restore the signal mask yet. Let do_signal() deliver * the signal on the way back to userspace, before the signal * mask is restored. */ if (sigmask) { memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); set_restore_sigmask(); } } else if (sigmask) sigprocmask(SIG_SETMASK, &sigsaved, NULL); return ret; } COMPAT_SYSCALL_DEFINE6(pselect6, int, n, compat_ulong_t __user *, inp, compat_ulong_t __user *, outp, compat_ulong_t __user *, exp, struct compat_timespec __user *, tsp, void __user *, sig) { compat_size_t sigsetsize = 0; compat_uptr_t up = 0; if (sig) { if (!access_ok(VERIFY_READ, sig, sizeof(compat_uptr_t)+sizeof(compat_size_t)) || __get_user(up, (compat_uptr_t __user *)sig) || __get_user(sigsetsize, (compat_size_t __user *)(sig+sizeof(up)))) return -EFAULT; } return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(up), sigsetsize); } COMPAT_SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds, struct compat_timespec __user *, tsp, const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize) { |
e99ca56ce move compat selec... |
1310 |
sigset_t ksigmask, sigsaved; |
36819ad09 select: Use get/p... |
1311 |
struct timespec64 ts, end_time, *to = NULL; |
e99ca56ce move compat selec... |
1312 1313 1314 |
int ret; if (tsp) { |
36819ad09 select: Use get/p... |
1315 |
if (compat_get_timespec64(&ts, tsp)) |
e99ca56ce move compat selec... |
1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 |
return -EFAULT; to = &end_time; if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec)) return -EINVAL; } if (sigmask) { if (sigsetsize != sizeof(compat_sigset_t)) return -EINVAL; |
3968cf623 get_compat_sigset() |
1326 |
if (get_compat_sigset(&ksigmask, sigmask)) |
e99ca56ce move compat selec... |
1327 |
return -EFAULT; |
e99ca56ce move compat selec... |
1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 |
sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); } ret = do_sys_poll(ufds, nfds, to); /* We can restart this syscall, usually */ if (ret == -EINTR) { /* * Don't restore the signal mask yet. Let do_signal() deliver * the signal on the way back to userspace, before the signal * mask is restored. */ if (sigmask) { memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); set_restore_sigmask(); } ret = -ERESTARTNOHAND; } else if (sigmask) sigprocmask(SIG_SETMASK, &sigsaved, NULL); ret = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret); return ret; } #endif |