move compat select-related syscalls to fs/select.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
368
fs/compat.c
368
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(¤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)
|
||||
{
|
||||
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(¤t->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
|
||||
|
||||
Reference in New Issue
Block a user