[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v2 1/2] linux-user: Add support for ppoll_time64() and pselec
|
From: |
Laurent Vivier |
|
Subject: |
Re: [PATCH v2 1/2] linux-user: Add support for ppoll_time64() and pselect6_time64() |
|
Date: |
Tue, 25 Aug 2020 17:23:38 +0200 |
|
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 |
Le 25/08/2020 à 09:17, Laurent Vivier a écrit :
> Le 25/08/2020 à 00:30, Filip Bozuta a écrit :
>> 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 <Filip.Bozuta@syrmia.com>
>> ---
>> linux-user/syscall.c | 462 +++++++++++++++++++++++--------------------
>> 1 file changed, 251 insertions(+), 211 deletions(-)
>>
>> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
>> index 1211e759c2..fc6a6e32e4 100644
>> --- a/linux-user/syscall.c
>> +++ b/linux-user/syscall.c
>> @@ -397,7 +397,7 @@ static int sys_getcwd1(char *buf, size_t size)
>> return strlen(buf)+1;
>> }
>>
>> -#ifdef TARGET_NR_utimensat
>> +#if defined(TARGET_NR_utimensat)
>> #if defined(__NR_utimensat)
>> #define __NR_sys_utimensat __NR_utimensat
>> _syscall4(int,sys_utimensat,int,dirfd,const char *,pathname,
>> @@ -763,11 +763,11 @@ 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)
>> @@ -984,7 +984,7 @@ 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)
>> @@ -1252,7 +1252,8 @@ static inline abi_long target_to_host_timespec(struct
>> timespec *host_ts,
>> }
>> #endif
>>
>> -#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64)
>> +#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_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_timespec(ts_addr, &ts)) {
>> + return -TARGET_EFAULT;
>> + }
>> + } else {
>> + if (ts_addr && host_to_target_timespec64(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
>> @@ -9045,106 +9277,11 @@ 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:
>> @@ -10076,114 +10213,17 @@ 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
>>
>
> Applied to my linux-user-for-5.2 branch.
I have removed it from my branch because this patch breaks "go run
hello.go" on armhf/bionic:
# cat /tmp/hello.go
package main
import "fmt"
func main() {
fmt.Println("Hello World!")
}
# go run /tmp/hello.go
fatal error: unexpected signal during runtime execution
fatal error: unexpected signal during runtime execution
panic during panic
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x0]
...
Thanks,
Laurent