[PATCH v3 5/5] io_pgetevents: use __kernel_timespec

From: Deepa Dinamani
Date: Sun Sep 16 2018 - 21:05:47 EST


struct timespec is not y2038 safe.
struct __kernel_timespec is the new y2038 safe structure for all
syscalls that are using struct timespec.
Update io_pgetevents 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_io_pgetevents
Compat : compat_sys_io_pgetevents_time64

Older y2038 unsafe syscalls:
(Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs)

Native 32 bit : sys_io_pgetevents_time32
Compat : compat_sys_io_pgetevents

Note that io_getevents syscalls do not have a y2038 safe solution.

Signed-off-by: Deepa Dinamani <deepa.kernel@xxxxxxxxx>
---
fs/aio.c | 85 ++++++++++++++++++++++++++++++++++++++--
include/linux/compat.h | 6 +++
include/linux/syscalls.h | 10 ++++-
3 files changed, 96 insertions(+), 5 deletions(-)

diff --git a/fs/aio.c b/fs/aio.c
index b81c216534d6..72dbce38a628 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -2063,11 +2063,13 @@ static long do_io_getevents(aio_context_t ctx_id,
* specifies an infinite timeout. Note that the timeout pointed to by
* timeout is relative. Will fail with -ENOSYS if not implemented.
*/
+#if !defined(CONFIG_64BIT_TIME) || defined(CONFIG_64BIT)
+
SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id,
long, min_nr,
long, nr,
struct io_event __user *, events,
- struct timespec __user *, timeout)
+ struct __kernel_timespec __user *, timeout)
{
struct timespec64 ts;
int ret;
@@ -2081,6 +2083,8 @@ SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id,
return ret;
}

+#endif
+
struct __aio_sigset {
const sigset_t __user *sigmask;
size_t sigsetsize;
@@ -2091,7 +2095,7 @@ SYSCALL_DEFINE6(io_pgetevents,
long, min_nr,
long, nr,
struct io_event __user *, events,
- struct timespec __user *, timeout,
+ struct __kernel_timespec __user *, timeout,
const struct __aio_sigset __user *, usig)
{
struct __aio_sigset ksig = { NULL, };
@@ -2118,7 +2122,44 @@ SYSCALL_DEFINE6(io_pgetevents,
return ret;
}

-#ifdef CONFIG_COMPAT
+#if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT)
+
+SYSCALL_DEFINE6(io_pgetevents_time32,
+ aio_context_t, ctx_id,
+ long, min_nr,
+ long, nr,
+ struct io_event __user *, events,
+ struct old_timespec32 __user *, timeout,
+ const struct __aio_sigset __user *, usig)
+{
+ struct __aio_sigset ksig = { NULL, };
+ sigset_t ksigmask, sigsaved;
+ struct timespec64 ts;
+ int ret;
+
+ if (timeout && unlikely(get_old_timespec32(&ts, timeout)))
+ return -EFAULT;
+
+ if (usig && copy_from_user(&ksig, usig, sizeof(ksig)))
+ return -EFAULT;
+
+
+ ret = set_user_sigmask(ksig.sigmask, &ksigmask, &sigsaved, ksig.sigsetsize);
+ if (ret)
+ return ret;
+
+ ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL);
+ restore_user_sigmask(ksig.sigmask, &sigsaved);
+ if (signal_pending(current) && !ret)
+ ret = -ERESTARTNOHAND;
+
+ return ret;
+}
+
+#endif
+
+#if defined(CONFIG_COMPAT_32BIT_TIME)
+
COMPAT_SYSCALL_DEFINE5(io_getevents, compat_aio_context_t, ctx_id,
compat_long_t, min_nr,
compat_long_t, nr,
@@ -2137,12 +2178,17 @@ COMPAT_SYSCALL_DEFINE5(io_getevents, compat_aio_context_t, ctx_id,
return ret;
}

+#endif
+
+#ifdef CONFIG_COMPAT

struct __compat_aio_sigset {
compat_sigset_t __user *sigmask;
compat_size_t sigsetsize;
};

+#if defined(CONFIG_COMPAT_32BIT_TIME)
+
COMPAT_SYSCALL_DEFINE6(io_pgetevents,
compat_aio_context_t, ctx_id,
compat_long_t, min_nr,
@@ -2173,4 +2219,37 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,

return ret;
}
+
+#endif
+
+COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
+ compat_aio_context_t, ctx_id,
+ compat_long_t, min_nr,
+ compat_long_t, nr,
+ struct io_event __user *, events,
+ struct __kernel_timespec __user *, timeout,
+ const struct __compat_aio_sigset __user *, usig)
+{
+ struct __compat_aio_sigset ksig = { NULL, };
+ sigset_t ksigmask, sigsaved;
+ struct timespec64 t;
+ int ret;
+
+ if (timeout && get_timespec64(&t, timeout))
+ return -EFAULT;
+
+ if (usig && copy_from_user(&ksig, usig, sizeof(ksig)))
+ return -EFAULT;
+
+ ret = set_compat_user_sigmask(ksig.sigmask, &ksigmask, &sigsaved, ksig.sigsetsize);
+ if (ret)
+ return ret;
+
+ ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL);
+ restore_user_sigmask(ksig.sigmask, &sigsaved);
+ if (signal_pending(current) && !ret)
+ ret = -ERESTARTNOHAND;
+
+ return ret;
+}
#endif
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 6896e6e51c00..50cd0329c8bf 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -556,6 +556,12 @@ asmlinkage long compat_sys_io_pgetevents(compat_aio_context_t ctx_id,
struct io_event __user *events,
struct old_timespec32 __user *timeout,
const struct __compat_aio_sigset __user *usig);
+asmlinkage long compat_sys_io_pgetevents_time64(compat_aio_context_t ctx_id,
+ compat_long_t min_nr,
+ compat_long_t nr,
+ struct io_event __user *events,
+ struct __kernel_timespec __user *timeout,
+ const struct __compat_aio_sigset __user *usig);

/* fs/cookies.c */
asmlinkage long compat_sys_lookup_dcookie(u32, u32, char __user *, compat_size_t);
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index e9cd0409c3fe..3ff0e29c082c 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -297,12 +297,18 @@ asmlinkage long sys_io_getevents(aio_context_t ctx_id,
long min_nr,
long nr,
struct io_event __user *events,
- struct timespec __user *timeout);
+ struct __kernel_timespec __user *timeout);
asmlinkage long sys_io_pgetevents(aio_context_t ctx_id,
long min_nr,
long nr,
struct io_event __user *events,
- struct timespec __user *timeout,
+ struct __kernel_timespec __user *timeout,
+ const struct __aio_sigset *sig);
+asmlinkage long sys_io_pgetevents_time32(aio_context_t ctx_id,
+ long min_nr,
+ long nr,
+ struct io_event __user *events,
+ struct old_timespec32 __user *timeout,
const struct __aio_sigset *sig);

/* fs/xattr.c */
--
2.17.1