diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/compat.c | 368 | ||||
| -rw-r--r-- | fs/select.c | 421 |
2 files changed, 419 insertions, 370 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(¤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 diff --git a/fs/select.c b/fs/select.c index e2112270d75a..dd70937ddb60 100644 --- a/fs/select.c +++ b/fs/select.c @@ -338,6 +338,53 @@ sticky: return ret; } +/* + * 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)); +} + #define FDS_IN(fds, n) (fds->in + n) #define FDS_OUT(fds, n) (fds->out + n) #define FDS_EX(fds, n) (fds->ex + n) @@ -401,7 +448,7 @@ static inline void wait_key_set(poll_table *wait, unsigned long in, wait->_key |= POLLOUT_SET; } -int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time) +static int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time) { ktime_t expire, *to = NULL; struct poll_wqueues table; @@ -881,7 +928,7 @@ static int do_poll(struct poll_list *list, struct poll_wqueues *wait, #define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \ sizeof(struct pollfd)) -int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, +static int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, struct timespec64 *end_time) { struct poll_wqueues table; @@ -1053,3 +1100,373 @@ SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds, return ret; } + +#ifdef CONFIG_COMPAT +#define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t)) + +static +int compat_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. + */ +static 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 = compat_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 = 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) +{ + 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 = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret); + + return ret; +} +#endif |