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authorDeepa Dinamani <deepa.kernel@gmail.com>2018-09-20 07:41:06 +0300
committerArnd Bergmann <arnd@arndb.de>2018-12-06 19:23:05 +0300
commit8bd27a3004e80d3d0962534c97e5a841262d5093 (patch)
treec613241d9e7fcf74ab50b8743d0b6ba8d8f729d6 /fs/select.c
parent854a6ed56839a40f6b5d02a2962f48841482eec4 (diff)
downloadlinux-8bd27a3004e80d3d0962534c97e5a841262d5093.tar.xz
ppoll: use __kernel_timespec
struct timespec is not y2038 safe. struct __kernel_timespec is the new y2038 safe structure for all syscalls that are using struct timespec. Update ppoll interfaces to use struct __kernel_timespec. sigset_t also has different representations on 32 bit and 64 bit architectures. Hence, we need to support the following different syscalls: New y2038 safe syscalls: (Controlled by CONFIG_64BIT_TIME for 32 bit ABIs) Native 64 bit(unchanged) and native 32 bit : sys_ppoll Compat : compat_sys_ppoll_time64 Older y2038 unsafe syscalls: (Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs) Native 32 bit : ppoll_time32 Compat : compat_sys_ppoll Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'fs/select.c')
-rw-r--r--fs/select.c166
1 files changed, 111 insertions, 55 deletions
diff --git a/fs/select.c b/fs/select.c
index eb9132520197..d332be059487 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -287,12 +287,18 @@ int poll_select_set_timeout(struct timespec64 *to, time64_t sec, long nsec)
return 0;
}
+enum poll_time_type {
+ PT_TIMEVAL = 0,
+ PT_OLD_TIMEVAL = 1,
+ PT_TIMESPEC = 2,
+ PT_OLD_TIMESPEC = 3,
+};
+
static int poll_select_copy_remaining(struct timespec64 *end_time,
void __user *p,
- int timeval, int ret)
+ enum poll_time_type pt_type, int ret)
{
struct timespec64 rts;
- struct timeval rtv;
if (!p)
return ret;
@@ -310,18 +316,40 @@ static int poll_select_copy_remaining(struct timespec64 *end_time,
rts.tv_sec = rts.tv_nsec = 0;
- if (timeval) {
- if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec))
- memset(&rtv, 0, sizeof(rtv));
- rtv.tv_sec = rts.tv_sec;
- rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
+ switch (pt_type) {
+ case PT_TIMEVAL:
+ {
+ struct timeval rtv;
- if (!copy_to_user(p, &rtv, sizeof(rtv)))
+ if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec))
+ memset(&rtv, 0, sizeof(rtv));
+ rtv.tv_sec = rts.tv_sec;
+ rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
+ if (!copy_to_user(p, &rtv, sizeof(rtv)))
+ return ret;
+ }
+ break;
+ case PT_OLD_TIMEVAL:
+ {
+ struct old_timeval32 rtv;
+
+ rtv.tv_sec = rts.tv_sec;
+ rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
+ if (!copy_to_user(p, &rtv, sizeof(rtv)))
+ return ret;
+ }
+ break;
+ case PT_TIMESPEC:
+ if (!put_timespec64(&rts, p))
return ret;
-
- } else if (!put_timespec64(&rts, p))
- return ret;
-
+ break;
+ case PT_OLD_TIMESPEC:
+ if (!put_old_timespec32(&rts, p))
+ return ret;
+ break;
+ default:
+ BUG();
+ }
/*
* If an application puts its timeval in read-only memory, we
* don't want the Linux-specific update to the timeval to
@@ -689,7 +717,7 @@ static int kern_select(int n, fd_set __user *inp, fd_set __user *outp,
}
ret = core_sys_select(n, inp, outp, exp, to);
- ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);
+ ret = poll_select_copy_remaining(&end_time, tvp, PT_TIMEVAL, ret);
return ret;
}
@@ -722,7 +750,7 @@ static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp,
return ret;
ret = core_sys_select(n, inp, outp, exp, to);
- ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
+ ret = poll_select_copy_remaining(&end_time, tsp, PT_TIMESPEC, ret);
restore_user_sigmask(sigmask, &sigsaved);
@@ -1026,7 +1054,7 @@ SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
}
SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
- struct timespec __user *, tsp, const sigset_t __user *, sigmask,
+ struct __kernel_timespec __user *, tsp, const sigset_t __user *, sigmask,
size_t, sigsetsize)
{
sigset_t ksigmask, sigsaved;
@@ -1054,60 +1082,50 @@ SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
- ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
+ ret = poll_select_copy_remaining(&end_time, tsp, PT_TIMESPEC, ret);
return ret;
}
-#ifdef CONFIG_COMPAT
-#define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
+#if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT)
-static
-int compat_poll_select_copy_remaining(struct timespec64 *end_time, void __user *p,
- int timeval, int ret)
+SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds, unsigned int, nfds,
+ struct old_timespec32 __user *, tsp, const sigset_t __user *, sigmask,
+ size_t, sigsetsize)
{
- struct timespec64 ts;
+ sigset_t ksigmask, sigsaved;
+ struct timespec64 ts, end_time, *to = NULL;
+ int ret;
- if (!p)
- return ret;
+ if (tsp) {
+ if (get_old_timespec32(&ts, tsp))
+ return -EFAULT;
- if (current->personality & STICKY_TIMEOUTS)
- goto sticky;
+ to = &end_time;
+ if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
+ return -EINVAL;
+ }
- /* No update for zero timeout */
- if (!end_time->tv_sec && !end_time->tv_nsec)
+ ret = set_user_sigmask(sigmask, &ksigmask, &sigsaved, sigsetsize);
+ if (ret)
return ret;
- ktime_get_ts64(&ts);
- ts = timespec64_sub(*end_time, ts);
- if (ts.tv_sec < 0)
- ts.tv_sec = ts.tv_nsec = 0;
+ ret = do_sys_poll(ufds, nfds, to);
- if (timeval) {
- struct old_timeval32 rtv;
+ restore_user_sigmask(sigmask, &sigsaved);
- rtv.tv_sec = ts.tv_sec;
- rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
+ /* We can restart this syscall, usually */
+ if (ret == -EINTR)
+ ret = -ERESTARTNOHAND;
- if (!copy_to_user(p, &rtv, sizeof(rtv)))
- return ret;
- } else {
- if (!put_old_timespec32(&ts, p))
- 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.
- */
+ ret = poll_select_copy_remaining(&end_time, tsp, PT_OLD_TIMESPEC, ret);
-sticky:
- if (ret == -ERESTARTNOHAND)
- ret = -EINTR;
return ret;
}
+#endif
+
+#ifdef CONFIG_COMPAT
+#define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
/*
* Ooo, nasty. We need here to frob 32-bit unsigned longs to
@@ -1239,7 +1257,7 @@ static int do_compat_select(int n, compat_ulong_t __user *inp,
}
ret = compat_core_sys_select(n, inp, outp, exp, to);
- ret = compat_poll_select_copy_remaining(&end_time, tvp, 1, ret);
+ ret = poll_select_copy_remaining(&end_time, tvp, PT_OLD_TIMEVAL, ret);
return ret;
}
@@ -1292,7 +1310,7 @@ static long do_compat_pselect(int n, compat_ulong_t __user *inp,
return ret;
ret = compat_core_sys_select(n, inp, outp, exp, to);
- ret = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret);
+ ret = poll_select_copy_remaining(&end_time, tsp, PT_OLD_TIMESPEC, ret);
restore_user_sigmask(sigmask, &sigsaved);
@@ -1318,6 +1336,7 @@ COMPAT_SYSCALL_DEFINE6(pselect6, int, n, compat_ulong_t __user *, inp,
sigsetsize);
}
+#if defined(CONFIG_COMPAT_32BIT_TIME)
COMPAT_SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds,
unsigned int, nfds, struct old_timespec32 __user *, tsp,
const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize)
@@ -1347,8 +1366,45 @@ COMPAT_SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds,
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
- ret = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret);
+ ret = poll_select_copy_remaining(&end_time, tsp, PT_OLD_TIMESPEC, ret);
return ret;
}
#endif
+
+/* New compat syscall for 64 bit time_t*/
+COMPAT_SYSCALL_DEFINE5(ppoll_time64, struct pollfd __user *, ufds,
+ unsigned int, nfds, struct __kernel_timespec __user *, tsp,
+ const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize)
+{
+ sigset_t ksigmask, sigsaved;
+ struct timespec64 ts, end_time, *to = NULL;
+ int ret;
+
+ if (tsp) {
+ if (get_timespec64(&ts, tsp))
+ return -EFAULT;
+
+ to = &end_time;
+ if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
+ return -EINVAL;
+ }
+
+ ret = set_compat_user_sigmask(sigmask, &ksigmask, &sigsaved, sigsetsize);
+ if (ret)
+ return ret;
+
+ ret = do_sys_poll(ufds, nfds, to);
+
+ restore_user_sigmask(sigmask, &sigsaved);
+
+ /* We can restart this syscall, usually */
+ if (ret == -EINTR)
+ ret = -ERESTARTNOHAND;
+
+ ret = poll_select_copy_remaining(&end_time, tsp, PT_TIMESPEC, ret);
+
+ return ret;
+}
+
+#endif