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authorAl Viro <viro@zeniv.linux.org.uk>2017-04-08 16:50:24 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2017-04-17 12:52:22 -0400
commite99ca56ce03dd90991025878152bae8b53484147 (patch)
tree51c7a65ac9f03ed4f242b042ae7d7416bc4f1b0f /fs/compat.c
parent2611dc1939569718c65ffd59c8fb9ba7474d026c (diff)
downloadlinux-e99ca56ce03dd90991025878152bae8b53484147.tar.bz2
move compat select-related syscalls to fs/select.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/compat.c')
-rw-r--r--fs/compat.c368
1 files changed, 0 insertions, 368 deletions
diff --git a/fs/compat.c b/fs/compat.c
index 54e5855e291a..bc15c23fae55 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -43,7 +43,6 @@
#include <linux/security.h>
#include <linux/highmem.h>
#include <linux/signal.h>
-#include <linux/poll.h>
#include <linux/mm.h>
#include <linux/fs_struct.h>
#include <linux/slab.h>
@@ -925,373 +924,6 @@ COMPAT_SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, fla
return do_sys_open(dfd, filename, flags, mode);
}
-#define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
-
-static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
- int timeval, int ret)
-{
- struct timespec ts;
-
- 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;
-
- ktime_get_ts(&ts);
- ts = timespec_sub(*end_time, ts);
- 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 {
- struct compat_timespec rts;
-
- rts.tv_sec = ts.tv_sec;
- rts.tv_nsec = ts.tv_nsec;
-
- if (!copy_to_user(p, &rts, sizeof(rts)))
- 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)
-{
- nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
- if (ufdset) {
- unsigned long odd;
-
- if (!access_ok(VERIFY_WRITE, ufdset, nr*sizeof(compat_ulong_t)))
- return -EFAULT;
-
- odd = nr & 1UL;
- nr &= ~1UL;
- while (nr) {
- unsigned long h, l;
- if (__get_user(l, ufdset) || __get_user(h, ufdset+1))
- return -EFAULT;
- ufdset += 2;
- *fdset++ = h << 32 | l;
- nr -= 2;
- }
- if (odd && __get_user(*fdset, ufdset))
- return -EFAULT;
- } else {
- /* Tricky, must clear full unsigned long in the
- * kernel fdset at the end, this makes sure that
- * actually happens.
- */
- memset(fdset, 0, ((nr + 1) & ~1)*sizeof(compat_ulong_t));
- }
- return 0;
-}
-
-static
-int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
- unsigned long *fdset)
-{
- unsigned long odd;
- nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
-
- if (!ufdset)
- return 0;
-
- odd = nr & 1UL;
- nr &= ~1UL;
- while (nr) {
- unsigned long h, l;
- l = *fdset++;
- h = l >> 32;
- if (__put_user(l, ufdset) || __put_user(h, ufdset+1))
- return -EFAULT;
- ufdset += 2;
- nr -= 2;
- }
- if (odd && __put_user(*fdset, ufdset))
- return -EFAULT;
- return 0;
-}
-
-
-/*
- * 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.
- */
-int compat_core_sys_select(int n, compat_ulong_t __user *inp,
- compat_ulong_t __user *outp, compat_ulong_t __user *exp,
- struct timespec *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(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;
-}
-
-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)
-{
- struct timespec end_time, *to = NULL;
- 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 = poll_select_copy_remaining(&end_time, tvp, 1, ret);
-
- return ret;
-}
-
-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 compat_sys_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,
- struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask,
- compat_size_t sigsetsize)
-{
- compat_sigset_t ss32;
- sigset_t ksigmask, sigsaved;
- struct compat_timespec ts;
- struct timespec end_time, *to = NULL;
- int ret;
-
- if (tsp) {
- if (copy_from_user(&ts, tsp, sizeof(ts)))
- 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;
- if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
- return -EFAULT;
- sigset_from_compat(&ksigmask, &ss32);
-
- sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
- sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
- }
-
- ret = compat_core_sys_select(n, inp, outp, exp, to);
- ret = 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(&current->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)
-{
- compat_sigset_t ss32;
- sigset_t ksigmask, sigsaved;
- struct compat_timespec ts;
- struct timespec end_time, *to = NULL;
- int ret;
-
- if (tsp) {
- if (copy_from_user(&ts, tsp, sizeof(ts)))
- 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;
- if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
- return -EFAULT;
- sigset_from_compat(&ksigmask, &ss32);
-
- 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(&current->saved_sigmask, &sigsaved,
- sizeof(sigsaved));
- set_restore_sigmask();
- }
- ret = -ERESTARTNOHAND;
- } else if (sigmask)
- sigprocmask(SIG_SETMASK, &sigsaved, NULL);
-
- ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
-
- return ret;
-}
-
#ifdef CONFIG_FHANDLE
/*
* Exactly like fs/open.c:sys_open_by_handle_at(), except that it