From e5ce9688b47a8f60337ce1e4108f35577494a46a Mon Sep 17 00:00:00 2001 From: Filip Bozuta Date: Tue, 25 Aug 2020 00:30:49 +0200 Subject: [PATCH] linux-user: Add support for ppoll_time64() and pselect6_time64() This patch introduces functionality for following time64 syscalls: *ppoll_time64 This is a year 2038 safe variant of: int poll(struct pollfd *fds, nfds_t nfds, int timeout) -- wait for some event on a file descriptor -- man page: https://man7.org/linux/man-pages/man2/ppoll.2.html *pselect6_time64 This is a year 2038 safe variant of: int pselect6(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, const struct timespec *timeout, const sigset_t *sigmask); -- synchronous I/O multiplexing -- man page: https://man7.org/linux/man-pages/man2/pselect6.2.html Implementation notes: Year 2038 safe syscalls in this patch were implemented with the same code as their regular variants (ppoll() and pselect()). This code was moved to new functions ('do_ppoll()' and 'do_pselect6()') that take a 'bool time64' from which a right 'struct timespec' converting function is called. (target_to_host/host_to_target_timespec() for regular and target_to_host/host_to_target_timespec64() for time64 variants) Signed-off-by: Filip Bozuta Reviewed-by: Laurent Vivier Message-Id: <20200824223050.92032-2-Filip.Bozuta@syrmia.com> [lv: rebase and fix do_pselect6()] Signed-off-by: Laurent Vivier --- linux-user/syscall.c | 460 +++++++++++++++++++++++-------------------- 1 file changed, 250 insertions(+), 210 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 93da3b9728..07220eee40 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -728,11 +728,11 @@ safe_syscall5(int, waitid, idtype_t, idtype, id_t, id, siginfo_t *, infop, \ int, options, struct rusage *, rusage) safe_syscall3(int, execve, const char *, filename, char **, argv, char **, envp) #if defined(TARGET_NR_select) || defined(TARGET_NR__newselect) || \ - defined(TARGET_NR_pselect6) + defined(TARGET_NR_pselect6) || defined(TARGET_NR_pselect6_time64) safe_syscall6(int, pselect6, int, nfds, fd_set *, readfds, fd_set *, writefds, \ fd_set *, exceptfds, struct timespec *, timeout, void *, sig) #endif -#if defined(TARGET_NR_ppoll) || defined(TARGET_NR_poll) +#if defined(TARGET_NR_ppoll) || defined(TARGET_NR_ppoll_time64) safe_syscall5(int, ppoll, struct pollfd *, ufds, unsigned int, nfds, struct timespec *, tsp, const sigset_t *, sigmask, size_t, sigsetsize) @@ -952,7 +952,7 @@ abi_long do_brk(abi_ulong new_brk) } #if defined(TARGET_NR_select) || defined(TARGET_NR__newselect) || \ - defined(TARGET_NR_pselect6) + defined(TARGET_NR_pselect6) || defined(TARGET_NR_pselect6_time64) static inline abi_long copy_from_user_fdset(fd_set *fds, abi_ulong target_fds_addr, int n) @@ -1250,7 +1250,8 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts, defined(TARGET_NR_rt_sigtimedwait_time64) || \ defined(TARGET_NR_utimensat) || \ defined(TARGET_NR_utimensat_time64) || \ - defined(TARGET_NR_semtimedop_time64) + defined(TARGET_NR_semtimedop_time64) || \ + defined(TARGET_NR_pselect6_time64) || defined(TARGET_NR_ppoll_time64) static inline abi_long target_to_host_timespec64(struct timespec *host_ts, abi_ulong target_addr) { @@ -1458,6 +1459,237 @@ static abi_long do_old_select(abi_ulong arg1) #endif #endif +#if defined(TARGET_NR_pselect6) || defined(TARGET_NR_pselect6_time64) +static abi_long do_pselect6(abi_long arg1, abi_long arg2, abi_long arg3, + abi_long arg4, abi_long arg5, abi_long arg6, + bool time64) +{ + abi_long rfd_addr, wfd_addr, efd_addr, n, ts_addr; + fd_set rfds, wfds, efds; + fd_set *rfds_ptr, *wfds_ptr, *efds_ptr; + struct timespec ts, *ts_ptr; + abi_long ret; + + /* + * The 6th arg is actually two args smashed together, + * so we cannot use the C library. + */ + sigset_t set; + struct { + sigset_t *set; + size_t size; + } sig, *sig_ptr; + + abi_ulong arg_sigset, arg_sigsize, *arg7; + target_sigset_t *target_sigset; + + n = arg1; + rfd_addr = arg2; + wfd_addr = arg3; + efd_addr = arg4; + ts_addr = arg5; + + ret = copy_from_user_fdset_ptr(&rfds, &rfds_ptr, rfd_addr, n); + if (ret) { + return ret; + } + ret = copy_from_user_fdset_ptr(&wfds, &wfds_ptr, wfd_addr, n); + if (ret) { + return ret; + } + ret = copy_from_user_fdset_ptr(&efds, &efds_ptr, efd_addr, n); + if (ret) { + return ret; + } + + /* + * This takes a timespec, and not a timeval, so we cannot + * use the do_select() helper ... + */ + if (ts_addr) { + if (time64) { + if (target_to_host_timespec64(&ts, ts_addr)) { + return -TARGET_EFAULT; + } + } else { + if (target_to_host_timespec(&ts, ts_addr)) { + return -TARGET_EFAULT; + } + } + ts_ptr = &ts; + } else { + ts_ptr = NULL; + } + + /* Extract the two packed args for the sigset */ + if (arg6) { + sig_ptr = &sig; + sig.size = SIGSET_T_SIZE; + + arg7 = lock_user(VERIFY_READ, arg6, sizeof(*arg7) * 2, 1); + if (!arg7) { + return -TARGET_EFAULT; + } + arg_sigset = tswapal(arg7[0]); + arg_sigsize = tswapal(arg7[1]); + unlock_user(arg7, arg6, 0); + + if (arg_sigset) { + sig.set = &set; + if (arg_sigsize != sizeof(*target_sigset)) { + /* Like the kernel, we enforce correct size sigsets */ + return -TARGET_EINVAL; + } + target_sigset = lock_user(VERIFY_READ, arg_sigset, + sizeof(*target_sigset), 1); + if (!target_sigset) { + return -TARGET_EFAULT; + } + target_to_host_sigset(&set, target_sigset); + unlock_user(target_sigset, arg_sigset, 0); + } else { + sig.set = NULL; + } + } else { + sig_ptr = NULL; + } + + ret = get_errno(safe_pselect6(n, rfds_ptr, wfds_ptr, efds_ptr, + ts_ptr, sig_ptr)); + + if (!is_error(ret)) { + if (rfd_addr && copy_to_user_fdset(rfd_addr, &rfds, n)) { + return -TARGET_EFAULT; + } + if (wfd_addr && copy_to_user_fdset(wfd_addr, &wfds, n)) { + return -TARGET_EFAULT; + } + if (efd_addr && copy_to_user_fdset(efd_addr, &efds, n)) { + return -TARGET_EFAULT; + } + if (time64) { + if (ts_addr && host_to_target_timespec64(ts_addr, &ts)) { + return -TARGET_EFAULT; + } + } else { + if (ts_addr && host_to_target_timespec(ts_addr, &ts)) { + return -TARGET_EFAULT; + } + } + } + return ret; +} +#endif + +#if defined(TARGET_NR_poll) || defined(TARGET_NR_ppoll) || \ + defined(TARGET_NR_ppoll_time64) +static abi_long do_ppoll(abi_long arg1, abi_long arg2, abi_long arg3, + abi_long arg4, abi_long arg5, bool ppoll, bool time64) +{ + struct target_pollfd *target_pfd; + unsigned int nfds = arg2; + struct pollfd *pfd; + unsigned int i; + abi_long ret; + + pfd = NULL; + target_pfd = NULL; + if (nfds) { + if (nfds > (INT_MAX / sizeof(struct target_pollfd))) { + return -TARGET_EINVAL; + } + target_pfd = lock_user(VERIFY_WRITE, arg1, + sizeof(struct target_pollfd) * nfds, 1); + if (!target_pfd) { + return -TARGET_EFAULT; + } + + pfd = alloca(sizeof(struct pollfd) * nfds); + for (i = 0; i < nfds; i++) { + pfd[i].fd = tswap32(target_pfd[i].fd); + pfd[i].events = tswap16(target_pfd[i].events); + } + } + if (ppoll) { + struct timespec _timeout_ts, *timeout_ts = &_timeout_ts; + target_sigset_t *target_set; + sigset_t _set, *set = &_set; + + if (arg3) { + if (time64) { + if (target_to_host_timespec64(timeout_ts, arg3)) { + unlock_user(target_pfd, arg1, 0); + return -TARGET_EFAULT; + } + } else { + if (target_to_host_timespec(timeout_ts, arg3)) { + unlock_user(target_pfd, arg1, 0); + return -TARGET_EFAULT; + } + } + } else { + timeout_ts = NULL; + } + + if (arg4) { + if (arg5 != sizeof(target_sigset_t)) { + unlock_user(target_pfd, arg1, 0); + return -TARGET_EINVAL; + } + + target_set = lock_user(VERIFY_READ, arg4, + sizeof(target_sigset_t), 1); + if (!target_set) { + unlock_user(target_pfd, arg1, 0); + return -TARGET_EFAULT; + } + target_to_host_sigset(set, target_set); + } else { + set = NULL; + } + + ret = get_errno(safe_ppoll(pfd, nfds, timeout_ts, + set, SIGSET_T_SIZE)); + + if (!is_error(ret) && arg3) { + if (time64) { + if (host_to_target_timespec64(arg3, timeout_ts)) { + return -TARGET_EFAULT; + } + } else { + if (host_to_target_timespec(arg3, timeout_ts)) { + return -TARGET_EFAULT; + } + } + } + if (arg4) { + unlock_user(target_set, arg4, 0); + } + } else { + struct timespec ts, *pts; + + if (arg3 >= 0) { + /* Convert ms to secs, ns */ + ts.tv_sec = arg3 / 1000; + ts.tv_nsec = (arg3 % 1000) * 1000000LL; + pts = &ts; + } else { + /* -ve poll() timeout means "infinite" */ + pts = NULL; + } + ret = get_errno(safe_ppoll(pfd, nfds, pts, NULL, 0)); + } + + if (!is_error(ret)) { + for (i = 0; i < nfds; i++) { + target_pfd[i].revents = tswap16(pfd[i].revents); + } + } + unlock_user(target_pfd, arg1, sizeof(struct target_pollfd) * nfds); + return ret; +} +#endif + static abi_long do_pipe2(int host_pipe[], int flags) { #ifdef CONFIG_PIPE2 @@ -9256,106 +9488,11 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, #endif #ifdef TARGET_NR_pselect6 case TARGET_NR_pselect6: - { - abi_long rfd_addr, wfd_addr, efd_addr, n, ts_addr; - fd_set rfds, wfds, efds; - fd_set *rfds_ptr, *wfds_ptr, *efds_ptr; - struct timespec ts, *ts_ptr; - - /* - * The 6th arg is actually two args smashed together, - * so we cannot use the C library. - */ - sigset_t set; - struct { - sigset_t *set; - size_t size; - } sig, *sig_ptr; - - abi_ulong arg_sigset, arg_sigsize, *arg7; - target_sigset_t *target_sigset; - - n = arg1; - rfd_addr = arg2; - wfd_addr = arg3; - efd_addr = arg4; - ts_addr = arg5; - - ret = copy_from_user_fdset_ptr(&rfds, &rfds_ptr, rfd_addr, n); - if (ret) { - return ret; - } - ret = copy_from_user_fdset_ptr(&wfds, &wfds_ptr, wfd_addr, n); - if (ret) { - return ret; - } - ret = copy_from_user_fdset_ptr(&efds, &efds_ptr, efd_addr, n); - if (ret) { - return ret; - } - - /* - * This takes a timespec, and not a timeval, so we cannot - * use the do_select() helper ... - */ - if (ts_addr) { - if (target_to_host_timespec(&ts, ts_addr)) { - return -TARGET_EFAULT; - } - ts_ptr = &ts; - } else { - ts_ptr = NULL; - } - - /* Extract the two packed args for the sigset */ - if (arg6) { - sig_ptr = &sig; - sig.size = SIGSET_T_SIZE; - - arg7 = lock_user(VERIFY_READ, arg6, sizeof(*arg7) * 2, 1); - if (!arg7) { - return -TARGET_EFAULT; - } - arg_sigset = tswapal(arg7[0]); - arg_sigsize = tswapal(arg7[1]); - unlock_user(arg7, arg6, 0); - - if (arg_sigset) { - sig.set = &set; - if (arg_sigsize != sizeof(*target_sigset)) { - /* Like the kernel, we enforce correct size sigsets */ - return -TARGET_EINVAL; - } - target_sigset = lock_user(VERIFY_READ, arg_sigset, - sizeof(*target_sigset), 1); - if (!target_sigset) { - return -TARGET_EFAULT; - } - target_to_host_sigset(&set, target_sigset); - unlock_user(target_sigset, arg_sigset, 0); - } else { - sig.set = NULL; - } - } else { - sig_ptr = NULL; - } - - ret = get_errno(safe_pselect6(n, rfds_ptr, wfds_ptr, efds_ptr, - ts_ptr, sig_ptr)); - - if (!is_error(ret)) { - if (rfd_addr && copy_to_user_fdset(rfd_addr, &rfds, n)) - return -TARGET_EFAULT; - if (wfd_addr && copy_to_user_fdset(wfd_addr, &wfds, n)) - return -TARGET_EFAULT; - if (efd_addr && copy_to_user_fdset(efd_addr, &efds, n)) - return -TARGET_EFAULT; - - if (ts_addr && host_to_target_timespec(ts_addr, &ts)) - return -TARGET_EFAULT; - } - } - return ret; + return do_pselect6(arg1, arg2, arg3, arg4, arg5, arg6, false); +#endif +#ifdef TARGET_NR_pselect6_time64 + case TARGET_NR_pselect6_time64: + return do_pselect6(arg1, arg2, arg3, arg4, arg5, arg6, true); #endif #ifdef TARGET_NR_symlink case TARGET_NR_symlink: @@ -10306,114 +10443,17 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, case TARGET_NR__newselect: return do_select(arg1, arg2, arg3, arg4, arg5); #endif -#if defined(TARGET_NR_poll) || defined(TARGET_NR_ppoll) -# ifdef TARGET_NR_poll +#ifdef TARGET_NR_poll case TARGET_NR_poll: -# endif -# ifdef TARGET_NR_ppoll + return do_ppoll(arg1, arg2, arg3, arg4, arg5, false, false); +#endif +#ifdef TARGET_NR_ppoll case TARGET_NR_ppoll: -# endif - { - struct target_pollfd *target_pfd; - unsigned int nfds = arg2; - struct pollfd *pfd; - unsigned int i; - - pfd = NULL; - target_pfd = NULL; - if (nfds) { - if (nfds > (INT_MAX / sizeof(struct target_pollfd))) { - return -TARGET_EINVAL; - } - - target_pfd = lock_user(VERIFY_WRITE, arg1, - sizeof(struct target_pollfd) * nfds, 1); - if (!target_pfd) { - return -TARGET_EFAULT; - } - - pfd = alloca(sizeof(struct pollfd) * nfds); - for (i = 0; i < nfds; i++) { - pfd[i].fd = tswap32(target_pfd[i].fd); - pfd[i].events = tswap16(target_pfd[i].events); - } - } - - switch (num) { -# ifdef TARGET_NR_ppoll - case TARGET_NR_ppoll: - { - struct timespec _timeout_ts, *timeout_ts = &_timeout_ts; - target_sigset_t *target_set; - sigset_t _set, *set = &_set; - - if (arg3) { - if (target_to_host_timespec(timeout_ts, arg3)) { - unlock_user(target_pfd, arg1, 0); - return -TARGET_EFAULT; - } - } else { - timeout_ts = NULL; - } - - if (arg4) { - if (arg5 != sizeof(target_sigset_t)) { - unlock_user(target_pfd, arg1, 0); - return -TARGET_EINVAL; - } - - target_set = lock_user(VERIFY_READ, arg4, sizeof(target_sigset_t), 1); - if (!target_set) { - unlock_user(target_pfd, arg1, 0); - return -TARGET_EFAULT; - } - target_to_host_sigset(set, target_set); - } else { - set = NULL; - } - - ret = get_errno(safe_ppoll(pfd, nfds, timeout_ts, - set, SIGSET_T_SIZE)); - - if (!is_error(ret) && arg3) { - host_to_target_timespec(arg3, timeout_ts); - } - if (arg4) { - unlock_user(target_set, arg4, 0); - } - break; - } -# endif -# ifdef TARGET_NR_poll - case TARGET_NR_poll: - { - struct timespec ts, *pts; - - if (arg3 >= 0) { - /* Convert ms to secs, ns */ - ts.tv_sec = arg3 / 1000; - ts.tv_nsec = (arg3 % 1000) * 1000000LL; - pts = &ts; - } else { - /* -ve poll() timeout means "infinite" */ - pts = NULL; - } - ret = get_errno(safe_ppoll(pfd, nfds, pts, NULL, 0)); - break; - } -# endif - default: - g_assert_not_reached(); - } - - if (!is_error(ret)) { - for(i = 0; i < nfds; i++) { - target_pfd[i].revents = tswap16(pfd[i].revents); - } - } - unlock_user(target_pfd, arg1, sizeof(struct target_pollfd) * nfds); - } - return ret; + return do_ppoll(arg1, arg2, arg3, arg4, arg5, true, false); +#endif +#ifdef TARGET_NR_ppoll_time64 + case TARGET_NR_ppoll_time64: + return do_ppoll(arg1, arg2, arg3, arg4, arg5, true, true); #endif case TARGET_NR_flock: /* NOTE: the flock constant seems to be the same for every