diff options
| author | Mikulas Patocka <mpatocka@redhat.com> | 2017-06-07 19:05:31 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-27 15:06:06 -0700 |
| commit | 78dce99f5497468e3f4e9de4e08c2b1db6c4b2e1 (patch) | |
| tree | 2c23bb71dcdd742bf60a6e024cc7120b87d0ef91 /drivers/md/raid5.c | |
| parent | 9b989b4d325b08f365212cc3bdd0c09dee0a72a0 (diff) | |
md: don't use flush_signals in userspace processes
commit f9c79bc05a2a91f4fba8bfd653579e066714b1ec upstream.
The function flush_signals clears all pending signals for the process. It
may be used by kernel threads when we need to prepare a kernel thread for
responding to signals. However using this function for an userspaces
processes is incorrect - clearing signals without the program expecting it
can cause misbehavior.
The raid1 and raid5 code uses flush_signals in its request routine because
it wants to prepare for an interruptible wait. This patch drops
flush_signals and uses sigprocmask instead to block all signals (including
SIGKILL) around the schedule() call. The signals are not lost, but the
schedule() call won't respond to them.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/md/raid5.c')
| -rw-r--r-- | drivers/md/raid5.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 4384b46cee1a..4bfd4170bd6a 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5279,12 +5279,15 @@ static void make_request(struct mddev *mddev, struct bio * bi) * userspace, we want an interruptible * wait. */ - flush_signals(current); prepare_to_wait(&conf->wait_for_overlap, &w, TASK_INTERRUPTIBLE); if (logical_sector >= mddev->suspend_lo && logical_sector < mddev->suspend_hi) { + sigset_t full, old; + sigfillset(&full); + sigprocmask(SIG_BLOCK, &full, &old); schedule(); + sigprocmask(SIG_SETMASK, &old, NULL); do_prepare = true; } goto retry; |