* FAILED: patch "[PATCH] signal: remove the wrong signal_pending() check in" failed to apply to 5.1-stable tree
@ 2019-07-01 14:17 gregkh
2019-07-02 17:28 ` Oleg Nesterov
0 siblings, 1 reply; 3+ messages in thread
From: gregkh @ 2019-07-01 14:17 UTC (permalink / raw)
To: oleg, David.Laight, akpm, arnd, axboe, dave, deepa.kernel, e,
ebiederm, jbaron, mtk.manpages, stable, tglx, torvalds, viro
Cc: stable
The patch below does not apply to the 5.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 97abc889ee296faf95ca0e978340fb7b942a3e32 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@redhat.com>
Date: Fri, 28 Jun 2019 12:06:50 -0700
Subject: [PATCH] signal: remove the wrong signal_pending() check in
restore_user_sigmask()
This is the minimal fix for stable, I'll send cleanups later.
Commit 854a6ed56839 ("signal: Add restore_user_sigmask()") introduced
the visible change which breaks user-space: a signal temporary unblocked
by set_user_sigmask() can be delivered even if the caller returns
success or timeout.
Change restore_user_sigmask() to accept the additional "interrupted"
argument which should be used instead of signal_pending() check, and
update the callers.
Eric said:
: For clarity. I don't think this is required by posix, or fundamentally to
: remove the races in select. It is what linux has always done and we have
: applications who care so I agree this fix is needed.
:
: Further in any case where the semantic change that this patch rolls back
: (aka where allowing a signal to be delivered and the select like call to
: complete) would be advantage we can do as well if not better by using
: signalfd.
:
: Michael is there any chance we can get this guarantee of the linux
: implementation of pselect and friends clearly documented. The guarantee
: that if the system call completes successfully we are guaranteed that no
: signal that is unblocked by using sigmask will be delivered?
Link: http://lkml.kernel.org/r/20190604134117.GA29963@redhat.com
Fixes: 854a6ed56839a40f6b5d02a2962f48841482eec4 ("signal: Add restore_user_sigmask()")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Eric Wong <e@80x24.org>
Tested-by: Eric Wong <e@80x24.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: <stable@vger.kernel.org> [5.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/aio.c b/fs/aio.c
index 3490d1fa0e16..c1e581dd32f5 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -2095,6 +2095,7 @@ SYSCALL_DEFINE6(io_pgetevents,
struct __aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 ts;
+ bool interrupted;
int ret;
if (timeout && unlikely(get_timespec64(&ts, timeout)))
@@ -2108,8 +2109,10 @@ SYSCALL_DEFINE6(io_pgetevents,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
@@ -2128,6 +2131,7 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
struct __aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 ts;
+ bool interrupted;
int ret;
if (timeout && unlikely(get_old_timespec32(&ts, timeout)))
@@ -2142,8 +2146,10 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
@@ -2193,6 +2199,7 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
struct __compat_aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 t;
+ bool interrupted;
int ret;
if (timeout && get_old_timespec32(&t, timeout))
@@ -2206,8 +2213,10 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
@@ -2226,6 +2235,7 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
struct __compat_aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 t;
+ bool interrupted;
int ret;
if (timeout && get_timespec64(&t, timeout))
@@ -2239,8 +2249,10 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index c6f513100cc9..4c74c768ae43 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2325,7 +2325,7 @@ SYSCALL_DEFINE6(epoll_pwait, int, epfd, struct epoll_event __user *, events,
error = do_epoll_wait(epfd, events, maxevents, timeout);
- restore_user_sigmask(sigmask, &sigsaved);
+ restore_user_sigmask(sigmask, &sigsaved, error == -EINTR);
return error;
}
@@ -2350,7 +2350,7 @@ COMPAT_SYSCALL_DEFINE6(epoll_pwait, int, epfd,
err = do_epoll_wait(epfd, events, maxevents, timeout);
- restore_user_sigmask(sigmask, &sigsaved);
+ restore_user_sigmask(sigmask, &sigsaved, err == -EINTR);
return err;
}
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 86a2bd721900..e6981d3f4468 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2201,11 +2201,12 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
}
ret = wait_event_interruptible(ctx->wait, io_cqring_events(ring) >= min_events);
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
if (sig)
- restore_user_sigmask(sig, &sigsaved);
+ restore_user_sigmask(sig, &sigsaved, ret == -ERESTARTSYS);
+
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
return READ_ONCE(ring->r.head) == READ_ONCE(ring->r.tail) ? ret : 0;
}
diff --git a/fs/select.c b/fs/select.c
index 6cbc9ff56ba0..a4d8f6e8b63c 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -758,10 +758,9 @@ 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);
+ restore_user_sigmask(sigmask, &sigsaved, ret == -ERESTARTNOHAND);
ret = poll_select_copy_remaining(&end_time, tsp, type, ret);
- restore_user_sigmask(sigmask, &sigsaved);
-
return ret;
}
@@ -1106,8 +1105,7 @@ SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
@@ -1142,8 +1140,7 @@ SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds, unsigned int, nfds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
@@ -1350,10 +1347,9 @@ static long do_compat_pselect(int n, compat_ulong_t __user *inp,
return ret;
ret = compat_core_sys_select(n, inp, outp, exp, to);
+ restore_user_sigmask(sigmask, &sigsaved, ret == -ERESTARTNOHAND);
ret = poll_select_copy_remaining(&end_time, tsp, type, ret);
- restore_user_sigmask(sigmask, &sigsaved);
-
return ret;
}
@@ -1425,8 +1421,7 @@ COMPAT_SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
@@ -1461,8 +1456,7 @@ COMPAT_SYSCALL_DEFINE5(ppoll_time64, struct pollfd __user *, ufds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 9702016734b1..78c2bb376954 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -276,7 +276,7 @@ extern int sigprocmask(int, sigset_t *, sigset_t *);
extern int set_user_sigmask(const sigset_t __user *usigmask, sigset_t *set,
sigset_t *oldset, size_t sigsetsize);
extern void restore_user_sigmask(const void __user *usigmask,
- sigset_t *sigsaved);
+ sigset_t *sigsaved, bool interrupted);
extern void set_current_blocked(sigset_t *);
extern void __set_current_blocked(const sigset_t *);
extern int show_unhandled_signals;
diff --git a/kernel/signal.c b/kernel/signal.c
index d622eac9d169..edf8915ddd54 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2912,7 +2912,8 @@ EXPORT_SYMBOL(set_compat_user_sigmask);
* This is useful for syscalls such as ppoll, pselect, io_pgetevents and
* epoll_pwait where a new sigmask is passed in from userland for the syscalls.
*/
-void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved)
+void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved,
+ bool interrupted)
{
if (!usigmask)
@@ -2922,7 +2923,7 @@ void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved)
* Restoring sigmask here can lead to delivering signals that the above
* syscalls are intended to block because of the sigmask passed in.
*/
- if (signal_pending(current)) {
+ if (interrupted) {
current->saved_sigmask = *sigsaved;
set_restore_sigmask();
return;
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: FAILED: patch "[PATCH] signal: remove the wrong signal_pending() check in" failed to apply to 5.1-stable tree
2019-07-01 14:17 FAILED: patch "[PATCH] signal: remove the wrong signal_pending() check in" failed to apply to 5.1-stable tree gregkh
@ 2019-07-02 17:28 ` Oleg Nesterov
2019-07-03 12:13 ` Greg KH
0 siblings, 1 reply; 3+ messages in thread
From: Oleg Nesterov @ 2019-07-02 17:28 UTC (permalink / raw)
To: gregkh
Cc: David.Laight, akpm, arnd, axboe, dave, deepa.kernel, e, ebiederm,
jbaron, mtk.manpages, stable, tglx, torvalds, viro
On 07/01, gregkh@linuxfoundation.org wrote:
>
> The patch below does not apply to the 5.1-stable tree.
...
> ------------------ original commit in Linus's tree ------------------
>
> From 97abc889ee296faf95ca0e978340fb7b942a3e32 Mon Sep 17 00:00:00 2001
> From: Oleg Nesterov <oleg@redhat.com>
> Date: Fri, 28 Jun 2019 12:06:50 -0700
> Subject: [PATCH] signal: remove the wrong signal_pending() check in
> restore_user_sigmask()
because 5.1 doesn't have fdb288a679cd ("io_uring: use wait_event_interruptible
for cq_wait conditional wait").
Please see the updated patch below. Compile tested...
---------------------------------------------------------------------
From 63fe93147d254350d473203f0bce8dacf08a1fbd Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@redhat.com>
Date: Tue, 2 Jul 2019 19:18:45 +0200
Subject: [PATCH] signal: remove the wrong signal_pending() check in
restore_user_sigmask()
This is the minimal fix for stable, I'll send cleanups later.
Commit 854a6ed56839 ("signal: Add restore_user_sigmask()") introduced
the visible change which breaks user-space: a signal temporary unblocked
by set_user_sigmask() can be delivered even if the caller returns
success or timeout.
Change restore_user_sigmask() to accept the additional "interrupted"
argument which should be used instead of signal_pending() check, and
update the callers.
Eric said:
: For clarity. I don't think this is required by posix, or fundamentally to
: remove the races in select. It is what linux has always done and we have
: applications who care so I agree this fix is needed.
:
: Further in any case where the semantic change that this patch rolls back
: (aka where allowing a signal to be delivered and the select like call to
: complete) would be advantage we can do as well if not better by using
: signalfd.
:
: Michael is there any chance we can get this guarantee of the linux
: implementation of pselect and friends clearly documented. The guarantee
: that if the system call completes successfully we are guaranteed that no
: signal that is unblocked by using sigmask will be delivered?
Link: http://lkml.kernel.org/r/20190604134117.GA29963@redhat.com
Fixes: 854a6ed56839a40f6b5d02a2962f48841482eec4 ("signal: Add restore_user_sigmask()")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Eric Wong <e@80x24.org>
Tested-by: Eric Wong <e@80x24.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: <stable@vger.kernel.org> [5.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
fs/aio.c | 28 ++++++++++++++++++++--------
fs/eventpoll.c | 4 ++--
fs/io_uring.c | 2 +-
fs/select.c | 18 ++++++------------
include/linux/signal.h | 2 +-
kernel/signal.c | 5 +++--
6 files changed, 33 insertions(+), 26 deletions(-)
diff --git a/fs/aio.c b/fs/aio.c
index 3490d1f..c1e581d 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -2095,6 +2095,7 @@ SYSCALL_DEFINE6(io_pgetevents,
struct __aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 ts;
+ bool interrupted;
int ret;
if (timeout && unlikely(get_timespec64(&ts, timeout)))
@@ -2108,8 +2109,10 @@ SYSCALL_DEFINE6(io_pgetevents,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
@@ -2128,6 +2131,7 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
struct __aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 ts;
+ bool interrupted;
int ret;
if (timeout && unlikely(get_old_timespec32(&ts, timeout)))
@@ -2142,8 +2146,10 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
@@ -2193,6 +2199,7 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
struct __compat_aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 t;
+ bool interrupted;
int ret;
if (timeout && get_old_timespec32(&t, timeout))
@@ -2206,8 +2213,10 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
@@ -2226,6 +2235,7 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
struct __compat_aio_sigset ksig = { NULL, };
sigset_t ksigmask, sigsaved;
struct timespec64 t;
+ bool interrupted;
int ret;
if (timeout && get_timespec64(&t, timeout))
@@ -2239,8 +2249,10 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
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)
+
+ interrupted = signal_pending(current);
+ restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+ if (interrupted && !ret)
ret = -ERESTARTNOHAND;
return ret;
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 4a0e98d..55c0e1c 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2330,7 +2330,7 @@ SYSCALL_DEFINE6(epoll_pwait, int, epfd, struct epoll_event __user *, events,
error = do_epoll_wait(epfd, events, maxevents, timeout);
- restore_user_sigmask(sigmask, &sigsaved);
+ restore_user_sigmask(sigmask, &sigsaved, error == -EINTR);
return error;
}
@@ -2355,7 +2355,7 @@ COMPAT_SYSCALL_DEFINE6(epoll_pwait, int, epfd,
err = do_epoll_wait(epfd, events, maxevents, timeout);
- restore_user_sigmask(sigmask, &sigsaved);
+ restore_user_sigmask(sigmask, &sigsaved, err == -EINTR);
return err;
}
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 84efb89..a304efd 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2097,7 +2097,7 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
finish_wait(&ctx->wait, &wait);
if (sig)
- restore_user_sigmask(sig, &sigsaved);
+ restore_user_sigmask(sig, &sigsaved, ret == -EINTR);
return READ_ONCE(ring->r.head) == READ_ONCE(ring->r.tail) ? ret : 0;
}
diff --git a/fs/select.c b/fs/select.c
index 6cbc9ff..a4d8f6e 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -758,10 +758,9 @@ 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);
+ restore_user_sigmask(sigmask, &sigsaved, ret == -ERESTARTNOHAND);
ret = poll_select_copy_remaining(&end_time, tsp, type, ret);
- restore_user_sigmask(sigmask, &sigsaved);
-
return ret;
}
@@ -1106,8 +1105,7 @@ SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
@@ -1142,8 +1140,7 @@ SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds, unsigned int, nfds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
@@ -1350,10 +1347,9 @@ static long do_compat_pselect(int n, compat_ulong_t __user *inp,
return ret;
ret = compat_core_sys_select(n, inp, outp, exp, to);
+ restore_user_sigmask(sigmask, &sigsaved, ret == -ERESTARTNOHAND);
ret = poll_select_copy_remaining(&end_time, tsp, type, ret);
- restore_user_sigmask(sigmask, &sigsaved);
-
return ret;
}
@@ -1425,8 +1421,7 @@ COMPAT_SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
@@ -1461,8 +1456,7 @@ COMPAT_SYSCALL_DEFINE5(ppoll_time64, struct pollfd __user *, ufds,
ret = do_sys_poll(ufds, nfds, to);
- restore_user_sigmask(sigmask, &sigsaved);
-
+ restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
/* We can restart this syscall, usually */
if (ret == -EINTR)
ret = -ERESTARTNOHAND;
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 9702016..78c2bb3 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -276,7 +276,7 @@ extern int sigprocmask(int, sigset_t *, sigset_t *);
extern int set_user_sigmask(const sigset_t __user *usigmask, sigset_t *set,
sigset_t *oldset, size_t sigsetsize);
extern void restore_user_sigmask(const void __user *usigmask,
- sigset_t *sigsaved);
+ sigset_t *sigsaved, bool interrupted);
extern void set_current_blocked(sigset_t *);
extern void __set_current_blocked(const sigset_t *);
extern int show_unhandled_signals;
diff --git a/kernel/signal.c b/kernel/signal.c
index 227ba17..3e2fd72 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2849,7 +2849,8 @@ EXPORT_SYMBOL(set_compat_user_sigmask);
* This is useful for syscalls such as ppoll, pselect, io_pgetevents and
* epoll_pwait where a new sigmask is passed in from userland for the syscalls.
*/
-void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved)
+void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved,
+ bool interrupted)
{
if (!usigmask)
@@ -2859,7 +2860,7 @@ void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved)
* Restoring sigmask here can lead to delivering signals that the above
* syscalls are intended to block because of the sigmask passed in.
*/
- if (signal_pending(current)) {
+ if (interrupted) {
current->saved_sigmask = *sigsaved;
set_restore_sigmask();
return;
--
2.5.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: FAILED: patch "[PATCH] signal: remove the wrong signal_pending() check in" failed to apply to 5.1-stable tree
2019-07-02 17:28 ` Oleg Nesterov
@ 2019-07-03 12:13 ` Greg KH
0 siblings, 0 replies; 3+ messages in thread
From: Greg KH @ 2019-07-03 12:13 UTC (permalink / raw)
To: Oleg Nesterov
Cc: David.Laight, akpm, arnd, axboe, dave, deepa.kernel, e, ebiederm,
jbaron, mtk.manpages, stable, tglx, torvalds, viro
On Tue, Jul 02, 2019 at 07:28:02PM +0200, Oleg Nesterov wrote:
> On 07/01, gregkh@linuxfoundation.org wrote:
> >
> > The patch below does not apply to the 5.1-stable tree.
> ...
> > ------------------ original commit in Linus's tree ------------------
> >
> > From 97abc889ee296faf95ca0e978340fb7b942a3e32 Mon Sep 17 00:00:00 2001
> > From: Oleg Nesterov <oleg@redhat.com>
> > Date: Fri, 28 Jun 2019 12:06:50 -0700
> > Subject: [PATCH] signal: remove the wrong signal_pending() check in
> > restore_user_sigmask()
>
> because 5.1 doesn't have fdb288a679cd ("io_uring: use wait_event_interruptible
> for cq_wait conditional wait").
>
> Please see the updated patch below. Compile tested...
Thanks for this, now queued up.
greg k-h
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-07-03 12:13 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2019-07-01 14:17 FAILED: patch "[PATCH] signal: remove the wrong signal_pending() check in" failed to apply to 5.1-stable tree gregkh
2019-07-02 17:28 ` Oleg Nesterov
2019-07-03 12:13 ` Greg KH
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