diff options
-rw-r--r-- | fs/select.c | 48 |
1 files changed, 23 insertions, 25 deletions
diff --git a/fs/select.c b/fs/select.c index a87f396f0313..25da26253485 100644 --- a/fs/select.c +++ b/fs/select.c @@ -812,34 +812,32 @@ static inline __poll_t do_pollfd(struct pollfd *pollfd, poll_table *pwait, bool *can_busy_poll, __poll_t busy_flag) { - __poll_t mask; - int fd; - - mask = 0; - fd = pollfd->fd; - if (fd >= 0) { - struct fd f = fdget(fd); - mask = EPOLLNVAL; - if (f.file) { - /* userland u16 ->events contains POLL... bitmap */ - __poll_t filter = demangle_poll(pollfd->events) | - EPOLLERR | EPOLLHUP; - mask = DEFAULT_POLLMASK; - if (f.file->f_op->poll) { - pwait->_key = filter; - pwait->_key |= busy_flag; - mask = f.file->f_op->poll(f.file, pwait); - if (mask & busy_flag) - *can_busy_poll = true; - } - /* Mask out unneeded events. */ - mask &= filter; - fdput(f); - } + int fd = pollfd->fd; + __poll_t mask = 0, filter; + struct fd f; + + if (fd < 0) + goto out; + mask = EPOLLNVAL; + f = fdget(fd); + if (!f.file) + goto out; + + /* userland u16 ->events contains POLL... bitmap */ + filter = demangle_poll(pollfd->events) | EPOLLERR | EPOLLHUP; + mask = DEFAULT_POLLMASK; + if (f.file->f_op->poll) { + pwait->_key = filter | busy_flag; + mask = f.file->f_op->poll(f.file, pwait); + if (mask & busy_flag) + *can_busy_poll = true; } + mask &= filter; /* Mask out unneeded events. */ + fdput(f); + +out: /* ... and so does ->revents */ pollfd->revents = mangle_poll(mask); - return mask; } |