[PATCH 6/6] io_pgetevents: deduplicate compat logic

From: Willem de Bruijn
Date: Mon Jan 11 2021 - 19:32:44 EST


From: Willem de Bruijn <willemb@xxxxxxxxxx>

io_pgetevents has four variants, including compat variants of both
timespec and sigmask.

With set_maybe_compat_user_sigmask helper, the latter can be
deduplicated. Move the shared logic to new do_io_pgetevents,
analogous to do_io_getevents.

Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Cc: Benjamin LaHaise <bcrl@xxxxxxxxx>
---
fs/aio.c | 94 ++++++++++++++++++++++----------------------------------
1 file changed, 37 insertions(+), 57 deletions(-)

diff --git a/fs/aio.c b/fs/aio.c
index d213be7b8a7e..56460ab47d64 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -2101,6 +2101,31 @@ struct __aio_sigset {
size_t sigsetsize;
};

+static long do_io_pgetevents(aio_context_t ctx_id,
+ long min_nr,
+ long nr,
+ struct io_event __user *events,
+ struct timespec64 *ts,
+ const void __user *umask,
+ size_t sigsetsize)
+{
+ bool interrupted;
+ int ret;
+
+ ret = set_maybe_compat_user_sigmask(umask, sigsetsize);
+ if (ret)
+ return ret;
+
+ ret = do_io_getevents(ctx_id, min_nr, nr, events, ts);
+
+ interrupted = signal_pending(current);
+ restore_saved_sigmask_unless(interrupted);
+ if (interrupted && !ret)
+ ret = -ERESTARTNOHAND;
+
+ return ret;
+}
+
SYSCALL_DEFINE6(io_pgetevents,
aio_context_t, ctx_id,
long, min_nr,
@@ -2111,8 +2136,6 @@ SYSCALL_DEFINE6(io_pgetevents,
{
struct __aio_sigset ksig = { NULL, };
struct timespec64 ts;
- bool interrupted;
- int ret;

if (timeout && unlikely(get_timespec64(&ts, timeout)))
return -EFAULT;
@@ -2120,18 +2143,9 @@ SYSCALL_DEFINE6(io_pgetevents,
if (usig && copy_from_user(&ksig, usig, sizeof(ksig)))
return -EFAULT;

- ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize);
- if (ret)
- return ret;
-
- ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL);
-
- interrupted = signal_pending(current);
- restore_saved_sigmask_unless(interrupted);
- if (interrupted && !ret)
- ret = -ERESTARTNOHAND;
-
- return ret;
+ return do_io_pgetevents(ctx_id, min_nr, nr, events,
+ timeout ? &ts : NULL,
+ ksig.sigmask, ksig.sigsetsize);
}

#if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT)
@@ -2146,8 +2160,6 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
{
struct __aio_sigset ksig = { NULL, };
struct timespec64 ts;
- bool interrupted;
- int ret;

if (timeout && unlikely(get_old_timespec32(&ts, timeout)))
return -EFAULT;
@@ -2155,19 +2167,9 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
if (usig && copy_from_user(&ksig, usig, sizeof(ksig)))
return -EFAULT;

-
- ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize);
- if (ret)
- return ret;
-
- ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL);
-
- interrupted = signal_pending(current);
- restore_saved_sigmask_unless(interrupted);
- if (interrupted && !ret)
- ret = -ERESTARTNOHAND;
-
- return ret;
+ return do_io_pgetevents(ctx_id, min_nr, nr, events,
+ timeout ? &ts : NULL,
+ ksig.sigmask, ksig.sigsetsize);
}

#endif
@@ -2213,8 +2215,6 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
{
struct __compat_aio_sigset ksig = { 0, };
struct timespec64 t;
- bool interrupted;
- int ret;

if (timeout && get_old_timespec32(&t, timeout))
return -EFAULT;
@@ -2222,18 +2222,9 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
if (usig && copy_from_user(&ksig, usig, sizeof(ksig)))
return -EFAULT;

- ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize);
- if (ret)
- return ret;
-
- ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL);
-
- interrupted = signal_pending(current);
- restore_saved_sigmask_unless(interrupted);
- if (interrupted && !ret)
- ret = -ERESTARTNOHAND;
-
- return ret;
+ return do_io_pgetevents(ctx_id, min_nr, nr, events,
+ timeout ? &t : NULL,
+ compat_ptr(ksig.sigmask), ksig.sigsetsize);
}

#endif
@@ -2248,8 +2239,6 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
{
struct __compat_aio_sigset ksig = { 0, };
struct timespec64 t;
- bool interrupted;
- int ret;

if (timeout && get_timespec64(&t, timeout))
return -EFAULT;
@@ -2257,17 +2246,8 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
if (usig && copy_from_user(&ksig, usig, sizeof(ksig)))
return -EFAULT;

- ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize);
- if (ret)
- return ret;
-
- ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL);
-
- interrupted = signal_pending(current);
- restore_saved_sigmask_unless(interrupted);
- if (interrupted && !ret)
- ret = -ERESTARTNOHAND;
-
- return ret;
+ return do_io_pgetevents(ctx_id, min_nr, nr, events,
+ timeout ? &t : NULL,
+ compat_ptr(ksig.sigmask), ksig.sigsetsize);
}
#endif
--
2.30.0.284.gd98b1dd5eaa7-goog