diff options
Diffstat (limited to 'fs/compat.c')
| -rw-r--r-- | fs/compat.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/fs/compat.c b/fs/compat.c index 0ec70e3cee0a..040a8be38a48 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -48,6 +48,7 @@ #include <linux/highmem.h> #include <linux/poll.h> #include <linux/mm.h> +#include <linux/eventpoll.h> #include <net/sock.h> /* siocdevprivate_ioctl */ @@ -2235,3 +2236,102 @@ long asmlinkage compat_sys_nfsservctl(int cmd, void *notused, void *notused2) return sys_ni_syscall(); } #endif + +#ifdef CONFIG_EPOLL + +#ifdef CONFIG_HAS_COMPAT_EPOLL_EVENT +asmlinkage long compat_sys_epoll_ctl(int epfd, int op, int fd, + struct compat_epoll_event __user *event) +{ + long err = 0; + struct compat_epoll_event user; + struct epoll_event __user *kernel = NULL; + + if (event) { + if (copy_from_user(&user, event, sizeof(user))) + return -EFAULT; + kernel = compat_alloc_user_space(sizeof(struct epoll_event)); + err |= __put_user(user.events, &kernel->events); + err |= __put_user(user.data, &kernel->data); + } + + return err ? err : sys_epoll_ctl(epfd, op, fd, kernel); +} + + +asmlinkage long compat_sys_epoll_wait(int epfd, + struct compat_epoll_event __user *events, + int maxevents, int timeout) +{ + long i, ret, err = 0; + struct epoll_event __user *kbuf; + struct epoll_event ev; + + if ((maxevents <= 0) || + (maxevents > (INT_MAX / sizeof(struct epoll_event)))) + return -EINVAL; + kbuf = compat_alloc_user_space(sizeof(struct epoll_event) * maxevents); + ret = sys_epoll_wait(epfd, kbuf, maxevents, timeout); + for (i = 0; i < ret; i++) { + err |= __get_user(ev.events, &kbuf[i].events); + err |= __get_user(ev.data, &kbuf[i].data); + err |= __put_user(ev.events, &events->events); + err |= __put_user_unaligned(ev.data, &events->data); + events++; + } + + return err ? -EFAULT: ret; +} +#endif /* CONFIG_HAS_COMPAT_EPOLL_EVENT */ + +#ifdef TIF_RESTORE_SIGMASK +asmlinkage long compat_sys_epoll_pwait(int epfd, + struct compat_epoll_event __user *events, + int maxevents, int timeout, + const compat_sigset_t __user *sigmask, + compat_size_t sigsetsize) +{ + long err; + compat_sigset_t csigmask; + sigset_t ksigmask, sigsaved; + + /* + * If the caller wants a certain signal mask to be set during the wait, + * we apply it here. + */ + if (sigmask) { + if (sigsetsize != sizeof(compat_sigset_t)) + return -EINVAL; + if (copy_from_user(&csigmask, sigmask, sizeof(csigmask))) + return -EFAULT; + sigset_from_compat(&ksigmask, &csigmask); + sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP)); + sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); + } + +#ifdef CONFIG_HAS_COMPAT_EPOLL_EVENT + err = compat_sys_epoll_wait(epfd, events, maxevents, timeout); +#else + err = sys_epoll_wait(epfd, events, maxevents, timeout); +#endif + + /* + * If we changed the signal mask, we need to restore the original one. + * In case we've got a signal while waiting, we do not restore the + * signal mask yet, and we allow do_signal() to deliver the signal on + * the way back to userspace, before the signal mask is restored. + */ + if (sigmask) { + if (err == -EINTR) { + memcpy(¤t->saved_sigmask, &sigsaved, + sizeof(sigsaved)); + set_thread_flag(TIF_RESTORE_SIGMASK); + } else + sigprocmask(SIG_SETMASK, &sigsaved, NULL); + } + + return err; +} +#endif /* TIF_RESTORE_SIGMASK */ + +#endif /* CONFIG_EPOLL */ |