signalfd: fill in ssi_int for posix timers and message queues

commit a2a20c412c86e0bb46a9ab0dd31bcfe6d201b913 upstream.

If signalfd is used to consume a signal generated by a POSIX interval
timer or POSIX message queue, the ssi_int field does not reflect the data
(sigevent->sigev_value) supplied to timer_create(2) or mq_notify(3).  (The
ssi_ptr field, however, is filled in.)

This behavior differs from signalfd's treatment of sigqueue-generated
signals -- see the default case in signalfd_copyinfo.  It also gives
results that differ from the case when a signal is handled conventionally
via a sigaction-registered handler.

So, set signalfd_siginfo->ssi_int in the remaining cases (__SI_TIMER,
__SI_MESGQ) where ssi_ptr is set.

akpm: a non-back-compatible change.  Merge into -stable to minimise the
number of kernels which are in the field and which miss this feature.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/signalfd.c b/fs/signalfd.c
index b07565c9438672015aa041e3fb57e4b01ca6e27c..d98bea8865c15b3c122c3e99d740c241330034a8 100644 (file)
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -87,6 +87,7 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo,
                 err |= __put_user(kinfo->si_tid, &uinfo->ssi_tid);
                 err |= __put_user(kinfo->si_overrun, &uinfo->ssi_overrun);
                 err |= __put_user((long) kinfo->si_ptr, &uinfo->ssi_ptr);
+                err |= __put_user(kinfo->si_int, &uinfo->ssi_int);
                break;
        case __SI_POLL:
                err |= __put_user(kinfo->si_band, &uinfo->ssi_band);
@@ -110,6 +111,7 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo,
                err |= __put_user(kinfo->si_pid, &uinfo->ssi_pid);
                err |= __put_user(kinfo->si_uid, &uinfo->ssi_uid);
                err |= __put_user((long) kinfo->si_ptr, &uinfo->ssi_ptr);
+               err |= __put_user(kinfo->si_int, &uinfo->ssi_int);
                break;
        default:
                /*